Summit Materials Inc.

04/03/2020 | Press release | Distributed by Public on 04/03/2020 20:12

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Summit Materials, Inc.
0001621563
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471984212
DE
1228
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34
001-36873
20773904
1550 WYNKOOP STREET, 3RD FLOOR
DENVER
CO
80202
303-893-0012
1550 WYNKOOP STREET, 3RD FLOOR
DENVER
CO
80202
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TABLE OF CONTENTS

Table of Contents

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549


SCHEDULE 14A
Proxy Statement Pursuant to Section 14(a)
of the
Securities Exchange Act of 1934
(Amendment No. )


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Soliciting Material under §240.14a-12

Summit Materials, Inc.
(Name of Registrant as Specified In Its Charter)
(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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Table of Contents

NOTICE OF 2020 ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD ON TUESDAY, MAY 19, 2020

The 2020 Annual Meeting of Stockholders (the 'Annual Meeting') of Summit Materials, Inc. ('Summit Materials' or the 'Company') will be held at 8:00 a.m., Mountain Time, on Tuesday, May 19, 2020. In light of COVID-19 (Coronavirus), the Annual Meeting will be completely virtual. You may attend the Annual Meeting, submit questions and vote your shares electronically during the meeting on the Internet through a virtual web conference at www.virtualshareholdermeeting.com/SUM2020. The Annual Meeting is being held for the following purposes:

1 To elect the two nominees for director, named in the attached Proxy Statement (the 'Proxy Statement') to serve until the 2023 Annual Meeting of Stockholders and until their respective successors are elected and qualified;

2


To approve, on a nonbinding advisory basis, the compensation of our named executive officers ('NEOs'), as disclosed in the Proxy Statement;

3


To ratify the appointment of KPMG LLP ('KPMG') as our independent registered public accounting firm for our fiscal year ending January 2, 2021; and

4


To transact such other business as may properly come before the Annual Meeting or any adjournment or postponement thereof.

Our Board of Directors recommends you vote (i) 'FOR' the election of each of the nominees to the Board; (ii) 'FOR' the approval, on a nonbinding advisory basis, of the compensation of our NEOs, as disclosed in the Proxy Statement; and (iii) 'FOR' the ratification of the appointment of KPMG as our independent registered public accounting firm.

The Board of Directors has fixed March 25, 2020 as the record date for determining stockholders entitled to receive notice of, and to vote at, the Annual Meeting or any adjournment or postponement thereof. Only stockholders of record at the close of business on that date will be entitled to notice of, and to vote at, the Annual Meeting. This Notice of 2020 Annual Meeting of Stockholders, Proxy Statement and form of proxy are being distributed and made available on or about April 3, 2020.

By Order of the Board of Directors



Anne Lee Benedict
Executive Vice President, Chief Legal Officer and Secretary

Denver, Colorado
April 3, 2020

Table of Contents

WHO WE ARE

Summit Materials is an integrated supplier of heavy-side construction materials such as aggregates, cement, ready-mix concrete, and asphalt, as well as paving services.

We offer customers a single-source provider for construction materials and related downstream products through our vertical integration. Our companies benefit from Summit's access to capital, IT resources, performance optimization practices and a proven management team. We believe this decentralized model allows us to realize the benefits of locally invested entrepreneurs with the expertise and economies of scale of a larger entity.

We provide over 6,000 jobs and believe our human capital is one of our most important assets. We support our employees with:

•Health insurance and wellness programs

•Training and development programs with broad participation throughout all levels of the Company

•An excellent safety track record

•Robust community engagement including support for local STEM education projects

Our geographic and end-user diversification and vertical integration help us withstand market cycles:

•We operate in 23 states and one Canadian province

•Our end market base is roughly one-third state infrastructure-related and approximately one-third residential and non-residential, respectively (based on net revenues)

We focus on sustainability and community involvement to secure a stable and profitable future:

•Environmental programs support profitability:

oRecycled approximately 483,000 tons of concrete and 4,600 tons of metal in 2019

oRecycled asphalt accounted for 17% of total tons produced in 2019, up from 16% in 2018

o40% of our cement plants' energy came from alternative fuel in 2019

•Approximately 3,600 students participated in educational events that we hosted

•Our employees volunteered more than 2,700 hours to their communities through company sponsored engagement

•Our vendor code of conduct, human rights, and environmental policies govern our interactions with our stakeholders

•Our sustainability website (summit-materials.com/sustainability/) further describes our deep commitment to the environment and communities in which we operate

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2019 PERFORMANCE

Operating income increased 31.4% to $213.6 million:

•Higher revenue driven by volume and price growth in all lines of business

•Strong organic growth in our aggregates business, led by our East Segment

•Resilient price and volume performance in our cement business despite challenging flooding conditions

•Net income of $61.1 million and record free cash flow of $180.9 million (a non-GAAP financial measure) as we were disciplined and selective in pursuing acquisitions while improving working capital management

•Reduced net leverage by nearly one full turn to 3.6X Adjusted EBITDA (a non-GAAP financial measure)

*See 'Reconciliation of Non-GAAP Measures to GAAP' on Annex A.

In 2019 net revenue increased 6.4% over 2018, and we reported earnings of $59.1 million, or $0.53 per basic share.

OUR GOVERNANCE

•Separate independent Chairman and CEO

•33% of Board members are female

•Age diversity on Board; short average tenure; no over-boarded directors

•Board includes senior operational and financial executives with materials, technology, supply chain and marketing expertise

DECLASSIFYING THE BOARD AND ELIMINATING SUPERMAJORITY VOTING

Our Board is currently divided into three classes. Each year our stockholders are asked to elect the directors comprising one of the classes for a three-year term. In addition, the Company's Amended and Restated Certificate of Incorporation (the 'Charter') requires the affirmative vote of the holders of at least 662/3% in voting power of all outstanding shares of stock of the Company to amend certain provisions of the Charter (the 'Supermajority Voting Requirement'). The Board believes that the classified board structure and Supermajority Voting Requirement served the Company well following its initial public offering ('IPO') in 2015 by promoting continuity and stability. However, the Board now feels, given the Company's continued growth following the IPO, that a classified board structure and Supermajority Voting Requirement are no longer necessary. Accordingly, the Board plans to include proposals at the Company's annual meeting of stockholders in 2021 to declassify the Board and remove the Supermajority Voting Requirement.

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Letter from the Chairman

To Our Valued Investors:

2019 was a year of substantial progress and improved financial performance at Summit Materials.

When I wrote to you last year, we were at the end of a challenging period for our company. At that time, I reiterated the Board's focus on supporting and advancing Summit's strategic objective to become a premier vertically integrated heavy-side materials company, and the Board's commitment to working alongside management to improve performance and drive earnings and revenue growth.

As a result of this focus and execution, Summit achieved much improved financial performance in 2019, including volume and price growth across all lines of business. The Aggregates business delivered outstanding performance, the Products business showed marked improvement, and our Cement business demonstrated resilience despite unprecedented flooding on the Mississippi River in the first half of the year. We are pleased with the positive momentum of each of our businesses, and the continued value we are providing to Summit's customers and employees.

However, we are also mindful that the economy has been significantly challenged early in 2020 by the COVID-19 global pandemic and acknowledge the heightened uncertainty related to the potential impacts of the virus on our future financial results. During this critical time, we are committed first and foremost to the health and well-being of our employees, our customers and the local communities where we operate. We will communicate additional market updates as more specific information becomes available.

We remain focused on delivering sustainable, long-term value to all Summit stockholders. The Board of Directors remains actively engaged in the business, including by meeting monthly with management to discuss operations, capital structure and expenditures, and in its strategic focus, including acquisitions, talent planning and incentive programs.

The Board of Directors is also committed to practicing good Corporate Governance. To that end we will ask shareholders in 2021 to approve i) the de-classification of the Summit Board of Directors, and ii) the elimination of the super-majority voting requirements in our Charter, Summit has maintained a classified board structure and supermajority voting requirements since its IPO in 2015 in order to promote continuity and stability. Given Summit's continued growth, the Board of Directors now believes these provisions are no longer necessary.

Finally, integral to our focus on ensuring the long-term value of Summit is a focus on being stewards of the environment and good corporate citizens in the communities in which we live and work. We continued to make progress in 2019 on this commitment to environmental and social responsibility. We recycled hundreds of thousands of tons of concrete, asphalt and metal. These efforts represented marked improvements from the prior year. We continued our partnership with the Wildlife Habitat Council to support biodiversity and educational programs on our properties, including over 1,700 acres that are now certified under the Council's standards at the end of 2019. Our employees logged more than 2,700 volunteer hours this year, a more than 60% increase above 2018, and 3,600 students participated in educational events we hosted.

On behalf of the Board of Directors, we thank you for your continued support as we work to continue advancing Summit's strategic efforts to drive sustainable, long-term shareholder value.

Sincerely,



Howard Lance
Chairman of the Board of Directors
Summit Materials, Inc.

Table of Contents

TABLE OF CONTENTS

OUR BOARD OF DIRECTORS

1

Item 1-Election of Directors

1

Who We Are

1

Directors Whose Terms Expire at the 2020 Annual Meeting

2

Directors Whose Terms Expire at the 2021 Annual Meeting

4

Directors Whose Terms Expire at the 2022 Annual Meeting

7

Director Not Standing for Reelection

9

Board Organization

10

Board Operations

14

Director Compensation

15

OUR PAY


16

Item 2-Nonbinding Advisory Vote on the Compensation or our NEOs

17

Compensation Committee Report

18

Compensation Discussion and Analysis-What We Paid

19

Compensation Discussion and Analysis-How We Paid

28

Compensation Tables

32

Narrative Disclosure to Summary Compensation Table and Grants of Plan-Based Awards Table

34

OUR AUDITORS


43

Item 3-Ratification of Appointment of KPMG

43

Independent Registered Public Accounting Firm

44

Audit Committee Report

45

Certain Relationships and Related Person Transactions

46

OUR STOCKHOLDERS


49

Holdings of Major Stockholders

49

Section 16(a) Beneficial Ownership Reporting Compliance

51

USERS' GUIDE


52

ANNEX A RECONCILIATION OF NON-GAAP MEASURES TO GAAP


57

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OUR BOARD OF DIRECTORS

ITEM 1

ELECTION OF DIRECTORS

Our Board currently has nine seats, divided into three classes: Class I, Class II and Class III. Each class consists, as nearly as possible, of one-third of the total number of directors.

•Our Class II directors are Ted A. Gardner, John R. Murphy and Steven H. Wunning, and their terms will expire at this Annual Meeting.

•Our Class III directors are Howard L. Lance, Anne K. Wade and Susan A. Ellerbusch, and their terms will expire at the 2021 Annual Meeting.

•Our Class I directors are Thomas W. Hill, Joseph S. Cantie and Anne M. Cooney, and their terms will expire at the 2022 Annual Meeting.

After discussions with Mr. Gardner and in order to effectuate his wishes, the Board determined not to nominate Mr. Gardner for reelection at this Annual Meeting. Immediately following the Annual Meeting, the size of the Board is expected to be reduced to eight members. The Board proposes that Messrs. Murphy and Wunning be reelected to Class II for new terms of three years each. Each nominee for director will, if elected, continue in office until the 2023 Annual Meeting and until the director's successor has been duly elected and qualified, or until the earlier of the director's death, resignation or removal. The proxy holders named on the proxy card intend to vote the proxy (if you are a stockholder of record) for the election of each of these nominees, unless you indicate on the proxy card that your vote should be withheld for any of the nominees. Under Securities and Exchange Commission ('SEC') rules, proxies cannot be voted for a greater number of persons than the number of nominees named.

Each nominee has consented to be named as a nominee in this Proxy Statement and to serve if elected. If any nominee is not able to serve, proxies will be voted in favor of the other nominees and may be voted for a substitute nominee, unless the Board chooses to reduce the number of directors serving on the Board.

THE BOARD RECOMMENDS A VOTE 'FOR' EACH NOMINEE

Who We Are

We, the members of your Board of Directors, take seriously our jobs of overseeing Summit Materials on your behalf and on behalf of our employees, customers, suppliers and other stakeholders, all of whom uniquely matter to us.

The Board has nominated two directors to be elected at the Annual Meeting to each serve for three-year terms ending with the 2023 Annual Meeting of Stockholders and until a successor is duly elected and qualified, or until the earlier of the director's death, resignation or removal. Each nominee is currently a director of the Company and has agreed to serve if elected. The age shown below for each director is as of May 19, 2020, which is the date of the Annual Meeting.

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Directors Whose Terms Expire at the 2020 Annual Meeting


John R. Murphy

Age: 69

Director since 2012

BOARD COMMITTEES

Audit (Chairman)

Nominating and Corporate Governance

OTHER BOARDS

O'Reilly Automotive, Inc.

Alight Solutions LLC

Apria Healthcare LLC

Previously, DJO Global Inc.

Previously, Accuride Corporation

John R. Murphy served as Summit Materials' Interim Chief Financial Officer from January 2013 to May 2013 and from July 2013 to October 2013.

Career Highlights

Senior Vice President and Chief Financial Officer of Smurfit-Stone Container Corporation (2009-2010)

Various senior management roles, including Chief Financial Officer and President and Chief Operating Officer and as President and Chief Executive Officer, of Accuride Corporation (1998-2008)

Skills / Experience

Financial expertise

Management experience

Education

BS in Accounting, Pennsylvania State University

MBA, University of Colorado

Also...

Mr. Murphy is a Certified Public Accountant.

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Steven H. Wunning

Age: 69

Director since 2016

BOARD COMMITTEES

Compensation (Chairman)

Nominating and Corporate Governance

OTHER BOARDS

The Sherwin Williams Company

Kennametal Inc.

Black & Veatch Holding Company

Previously, Neovia Logistics Services, LLC

Steven H. Wunning served as Group President and Executive Office Member for Caterpillar Inc. ('Caterpillar') from January 2004 until his retirement in February 2015. He joined Caterpillar in 1973.

Career Highlights

Group President and Executive Office Member for Caterpillar from January 2004 until his retirement in February 2015.

Various executive positions at Caterpillar, including Vice President, Logistics Division from January 2000 to January 2004 and Vice President, Logistics & Product Services Division from November 1998 to January 2000.

Skills / Experience

Extensive board and management experience

Industrial and building products industry expertise

Education

BS in Metallurgical Engineering from Missouri University of Science and Technology

MBA, University of Illinois Urbana-Champaign

Also...

Mr. Wunning serves on the Board of Trustees of Missouri University of Science and Technology.

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Directors Whose Terms Expire at the 2021 Annual Meeting


Howard L. Lance

Age: 64

Director since 2012

Chairman since 2013

BOARD COMMITTEES

Compensation

Nominating and Corporate Governance

OTHER BOARDS

Change Healthcare, Inc.

Previously, Maxar Technologies Ltd.

Previously, Harris Corporation

Howard L. Lance is the former President and Chief Executive Officer of Maxar Technologies Inc. and its predecessor MacDonald, Dettwiler and Associates Ltd., a global communications and information company, a position he held from May 2016 until January 2019.

Career Highlights

President and Chief Executive Officer, Maxar Technologies Inc. (May 2016-January 2019)

Executive Advisor to The Blackstone Group L.P. (2012-April 2016)

President & CEO, Harris Corporation (2003-2011)

Skills / Experience

Leadership experience

Extensive management and operational experience

Education

BS in Industrial Engineering, Bradley University

MS in Management from the Krannert School of Management at Purdue University


Also...

Before joining Harris Corporation, Mr. Lance was co-president of NCR Corporation and Chief Operating Officer of its Retail and Financial Group. Previously, he spent 17 years with Emerson Electric Co., where he held senior management positions including Executive Vice President of its Electronics and Telecommunications segment, Chief Executive Officer and director of its Astec electronics subsidiary in Hong Kong, Group Vice President of its Climate Technologies segment and President of its Copeland Refrigeration division.

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Anne K. Wade

Age: 48

Director since 2016

BOARD COMMITTEES

Audit

OTHER BOARDS

Man Group plc

John Laing Group plc

Big Society Capital Ltd.

Anne K. Wade is currently a partner at Leaders' Quest, an organization focused on culture, values, and driving social and financial impact in major corporations.

Career Highlights

As part of Leaders' Quest, Co-Director of the Banking Futures initiative in the UK (2014-2017)

Senior Vice President and Director, Capital International, a part of the Capital Group Companies (1995-2012)

Skills / Experience

Financial and investing experience

Extensive knowledge of infrastructure sectors

Education

BA, magna cum laude, Harvard University

MS, London School of Economics

Also...

Ms. Wade is a Member of the Board of Trustees of the Heron Foundation in New York.

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Susan A. Ellerbusch

Age: 52

Director since 2018

BOARD COMMITTEES

Audit

In September 2019, Susan A. Ellerbusch was promoted to Chief Executive Officer of Air Liquide North America LLC, the North American subsidiary of Air Liquide S.A., a world leader in gases, technologies and services for industry and health, with a presence in 80 countries and more than 3 million customers and patients.

Career Highlights

Chief Executive Officer of Air Liquide USA LLC (June 2017-September 2019)

President, Air Liquide Large Industries U.S. (September 2015-June 2017)

Various executive positions, including President, BP Biofuels North America from 2008 to 2015

Skills / Experience

Management and operational experience

Extensive knowledge of chemicals and energy industries

Education

BS in genetics, University of Illinois Urbana-Champaign

MBA, University of Illinois Chicago

Also...

As head of Air Liquide's operations in the U.S. and Canada, Ms. Ellerbusch leads the company's Large Industries, Industrial Merchant, Health Care, Hydrogen Mobility and Electronics businesses.

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Directors Whose Terms Expire at the 2022 Annual Meeting


Thomas W. Hill

Age: 64

Director since 2009

BOARD COMMITTEES

N/A

Thomas W. Hill is the founder of Summit Materials and has been President and Chief Executive Officer since its inception, and he has been a member of the Board of Directors since August 2009.

Career Highlights

Founder of Summit Materials and has served as President and Chief Executive Officer since its inception

Chief Executive Officer, Oldcastle, Inc. (2006-2008)

Ran the Materials division of Oldcastle (1992-2006)

Skills / Experience

Extensive knowledge of industry

Leadership experience

Education

BA in Economics and History, Duke University

MBA, Trinity College in Dublin, Ireland

Also...

Served as Chairman of the American Road and Transportation Builders Association during congressional consideration of the multiyear transportation bill 'SAFETEA LU' and remains active with its Executive Committee. Mr. Hill has also been Treasurer of both the National Asphalt Pavement Association and the National Stone Association (a predecessor of The National Stone, Sand & Gravel Association) and sits on the board of the Wildlife Habitat Council, a non-profit organization that promotes and certifies habitat conservation and management on corporate lands through partnerships and education.

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Joseph S. Cantie

Age: 56

Director since 2016

BOARD COMMITTEES

Audit

OTHER BOARDS

TopBuild Corp

Delphi Technologies PLC

Howmet Aerospace Inc.

Joseph S. Cantie is the former Executive Vice President and Chief Financial Officer of ZF TRW, a division of ZF Friedrichshafen AG, a global automotive supplier, a position he held from May 2015 until January 2016.

Career Highlights

Executive Vice President and Chief Financial Officer of TRW Automotive Holdings Corp., which was acquired by ZF Industries in May 2015 (2003-2015)

Various executive positions at TRW Automotive Holdings Corp. (1999-2003)

Various executive positions, including Vice President and Controller of LucasVarity Plc (1996-1999)

Skills / Experience

Financial and operating experience

Extensive knowledge of the industrial sector

Education

BS, State University of New York at Buffalo

Also...

Mr. Cantie spent 10 years at KPMG and is a certified public accountant.

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Anne M. Cooney

Age: 60

Director since 2018

BOARD COMMITTEES

Compensation

Nominating and Corporate Governance

OTHER BOARDS

The Manitowoc Company, Inc.

Previously, Machinery and Allied Products Institute

Anne M. Cooney is the former President of the Process Industries and Drives Division of Siemens Industry, Inc., a division of Siemens AG, a multinational conglomerate primarily engaged in industrial engineering, electronics, energy, healthcare and infrastructure activities, a position she held from October 2014 until her retirement in December 2018.

Career Highlights

President, Process Industries and Drives Division of Siemens Industry, Inc. (2014-2018)

Chief Operating Officer for Siemens Healthcare's Diagnostics division (2011-2014)

President, Drives Technologies Division, Siemens Industry, Inc. (2009-2011)

Skills / Experience

Leadership experience

Management and operational experience

Education

BS in Industrial Management, Gannon University

MBA, Emory University

Director Not Standing for Reelection

After discussions with Mr. Gardner and in order to effectuate his wishes, the Board determined not to nominate Mr. Gardner for reelection at this Annual Meeting. We thank Mr. Gardner for his invaluable service.

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Board Organization

Good corporate governance at Summit Materials starts at the top-with how we, as a Board, are governed. We believe our board governance incorporates best-practice standards as appropriate for our Company:

•We have an independent board chairman

•All members of our committees are independent

•All of our non-employee directors are independent

•All directors may request that items be added to the Board's agenda or the agenda of any committee on which they serve

Our Board is currently divided into three classes. Each year our stockholders are asked to elect the directors comprising one of the classes for a three-year term. The Board believes that the classified board structure served the Company well following its IPO by promoting continuity and stability. However, the Board now feels, given the Company's continued growth following the IPO, that a classified board structure and Supermajority Voting Requirement are no longer necessary. Accordingly, the Board plans to include a proposal at the Company's annual meeting of stockholders in 2021 to declassify the Board.

Director Independence Determination

Under our Corporate Governance Guidelines and the NYSE corporate governance rules for listed companies, a director is not independent unless the Board affirmatively determines that he or she does not have a direct or indirect material relationship with us or any of our subsidiaries. In addition, the director must meet the bright-line test for independence set forth by the NYSE rules. Our Corporate Governance Guidelines define independence in accordance with the independence definition in the current NYSE rules. Our Corporate Governance Guidelines require the Board to review the independence of all directors at least annually. In the event a director has a relationship with the Company that is relevant to his or her independence and is not addressed by the objective tests set forth in the NYSE independence definition, the Board will determine, considering all relevant facts and circumstances, whether such relationship is material.

Our Board has affirmatively determined that each of Messrs. Cantie, Gardner, Lance, Murphy, and Wunning and each of Mss. Cooney, Ellerbusch and Wade is independent, under the guidelines for director independence set forth in the Corporate Governance Guidelines and under all applicable NYSE rules, including with respect to applicable committee membership. Our Board also has determined that each of the members of the Audit Committee, Messrs. Cantie and Murphy and Mss. Ellerbusch and Wade, is 'independent' for purposes of Section 10A(m)(3) of the Securities Exchange Act of 1934, as amended (the 'Exchange Act').

In making its independence determinations, the Board considered and reviewed all information known to it, including information identified through annual directors' questionnaires.

Board Leadership

The Board directs and oversees the management of the business and affairs of the Company in a manner consistent with the best interests of the Company. The Board's responsibility is one of oversight, and in performing its oversight role, the Board serves as the ultimate decision-making body of the Company, except for those matters reserved to or shared with our stockholders.

In accordance with the Company's belief that its long-term success includes being good stewards of the environment, the Board oversees and supports the Company's initiatives in these areas. In addition, the Board takes pride in supporting the Company's efforts to offer a safe work environment to its employees and being a good corporate citizen in its local communities.

In accordance with our Corporate Governance Guidelines, the Board selects the Company's Chairman and the Company's CEO in any way it considers in the best interests of the Company and, accordingly, does not have a policy on whether the roles of Chairman and CEO should be separate or combined and, if separate, whether the Chairman should be selected from the independent directors. We believe that the separation of the Chairman of the Board and CEO positions is appropriate corporate governance for us as this time. Accordingly, Mr. Lance serves as the Chairman of the Board while Mr. Hill serves as our CEO. Our Board believes that this structure best encourages the free and open dialogue of differing views and provides for strong checks and balances.

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Corporate Governance Documents

Our investor relations website at investors.summit-materials.com/govdocs, 'Governance Documents,' has additional information on our board governance and corporate governance, including our Corporate Governance Guidelines, our Code of Business Conduct and Ethics; and the charters approved by the Board for the Audit Committee, the Compensation Committee and the Nominating and Corporate Governance Committee.

Board Meetings and Committees

The Board meets regularly during the year and holds special meetings and acts by unanimous written consent when circumstances require. During 2019, there were eight (8) meetings of the Board. Each director attended at least 75% of the aggregate of the total number of meetings of the Board (held during the period for which he or she was a director) and the total number of meetings held by all committees on which he or she served (during the periods that he or she served) during 2019. In addition, directors are expected to make every effort to attend any meetings of stockholders. All of our directors attended the 2019 Annual Meeting of Stockholders.

The Board has established an Audit Committee, a Compensation Committee, and a Nominating and Corporate Governance Committee (collectively, the 'Committees'). The Committees keep the Board informed of their actions and assist the Board in fulfilling its oversight responsibility to stockholders. The table below provides current membership information as well as meeting information for the last fiscal year.

Name
Audit Committee
Compensation Committee
Nominating and Corporate
Governance Committee

Thomas W. Hill

Howard L. Lance*

· ·

Joseph S. Cantie

·

Anne M. Cooney(1)

· ·

Susan A. Ellerbusch

·

Ted A. Gardner(2)

· Chair

John R. Murphy

Chair ·

Anne K. Wade

·

Steven H. Wunning

Chair ·

Total Meetings in 2019

5 4 4
*Independent chairman of the Board.

(1)The Company expects Ms. Cooney to replace Mr. Gardner as chair of the Nominating and Corporate Governance Committee following the Annual Meeting.

(2)After discussions with Mr. Gardner and in order to effectuate his wishes, the Board determined not to nominate Mr. Gardner for reelection at this Annual Meeting.

The functions performed by these Committees, which are set forth in more detail in their charters, are summarized below.

Audit Committee

Our Audit Committee consists of Messrs. Murphy and Cantie and Mss. Ellerbusch and Wade, with Mr. Murphy serving as chair.

Our Audit Committee is responsible for, among other things:

•selecting and hiring our independent registered public accounting firm, and approving the audit and non-audit services to be performed by our independent registered public accounting firm;

•assisting the Board in evaluating the qualifications, performance and independence of our independent registered public accounting firm;

•assisting the Board in monitoring the quality and integrity of our financial statements and our accounting and financial reporting;

•assisting the Board in monitoring our compliance with legal and regulatory requirements;

•reviewing the adequacy and effectiveness of our internal control over financial reporting;

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•assisting the Board in monitoring the performance of our internal audit function;

•reviewing with management and our independent registered public accounting firm our annual and quarterly financial statements;

•establishing procedures for the receipt, retention and treatment of complaints received by the Company regarding accounting, internal accounting controls or auditing matters and the confidential, anonymous submission by our employees of concerns regarding questionable accounting or auditing matters;

•preparing the Audit Committee Report that the rules and regulations of the SEC require to be included in our annual proxy statement;

•review and discuss with management and our independent registered public accounting our guidelines and policies with respect to risk assessment and risk management, including the major financial risk exposures and the steps management has taken to monitor and control such exposures; and

•review our information technology security controls with our Head of Information Technology and evaluate the adequacy of our information technology security program, compliance and controls with the Head of Information Technology.

Audit Committee Member Independence; Financial Literacy; Financial Expert


Independent under NYSE
governance standards
and Rule 10A-3 of Exchange Act

Financially Literate
Audit Committee
Financial Expert

John R. Murphy (Chair)

Joseph S. Cantie

Susan A. Ellerbusch

Anne K. Wade

Compensation Committee

Our Compensation Committee consists of Messrs. Wunning, Gardner and Lance and Ms. Cooney, with Mr. Wunning serving as chair.

Our Compensation Committee is responsible for, among other things:

•reviewing and approving or making recommendations to the Board with respect to corporate goals and objectives relevant to the compensation of our Chief Executive Officer, evaluating his/her performance in light of those goals and objectives and determining and approving his/her compensation level based on such evaluation;

•reviewing and approving, or making recommendations to the Board with respect to, the compensation of our other executive officers, including annual base salary, bonus, equity-based incentives and other benefits;

•reviewing and recommending the compensation of our directors;

•reviewing and discussing annually with management our 'Compensation Discussion and Analysis' disclosure required by SEC rules;

•preparing the Compensation Committee Report required by the SEC to be included in our annual proxy statement; and

•reviewing and making recommendations with respect to our equity compensation plans.

Nominating and Corporate Governance Committee

Our Nominating and Corporate Governance Committee consists of Messrs. Gardner, Lance, Murphy, and Wunning and Ms. Cooney, with Mr. Gardner serving as chair. The Company expects Ms. Cooney to replace Mr. Gardner as chair of the Nominating and Corporate Governance Committee following the Annual Meeting.

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Our Nominating and Corporate Governance Committee is responsible for, among other things:

•assisting our Board in identifying prospective director nominees and recommending nominees to the Board;

•overseeing the evaluation of the Board and management;

•reviewing and advising the Board on developments in corporate governance practices;

•developing and recommending a set of corporate governance guidelines; and

•recommending members for each committee of our Board.

Director Nominations

The Nominating and Corporate Governance Committee identifies individuals believed to be qualified as candidates to serve on the Board and selects, or recommends that the Board select, the nominees for all directorships to be filled by the Board or by our stockholders at an annual or special meeting.

In identifying candidates for membership on the Board, the Committee takes into account all factors it considers appropriate, which may include:

•individual qualifications, including strength of character, mature judgment, familiarity with the Company's business and industry, independence of thought and an ability to work collegially; and

•all other factors the Committee considers appropriate, which may include age, diversity of background, existing commitments to other businesses, potential conflicts of interest with other pursuits, legal considerations such as antitrust issues, corporate governance background, relevant career experience, relevant technical skills, relevant business or government acumen, financial and accounting background, executive compensation background and the size, composition and combined expertise of the existing Board.

Although the Nominating and Corporate Governance Committee considers diversity in all its forms, including diversity of viewpoints, background and experiences, the Company does not have a formal diversity policy. The Committee also may consider the extent to which the candidate would fill a present need on the Board. When evaluating whether to re-nominate existing directors, the Committee considers matters relating to the retirement of current directors, as well as the performance of such directors.

The Nominating and Corporate Governance Committee evaluates director candidates recommended by stockholders on the same basis as it considers other nominees. Any recommendation submitted to the Chief Legal Officer and Secretary should be in writing and should include any supporting material the stockholder considers appropriate in support of that recommendation, but must include information that would be required under the rules of the SEC to be included in a proxy statement soliciting proxies for the election of such candidate and the written consent of the candidate to serve as one of our directors, if elected. Stockholders wishing to propose a candidate for consideration may do so by submitting the above information to the attention of the Chief Legal Officer and Secretary, Summit Materials, Inc., 1550 Wynkoop Street, 3rd Floor, Denver, Colorado 80202. All recommendations for nomination received by the Chief Legal Officer and Secretary that satisfy the requirements of our Amended and Restated Bylaws (the 'Bylaws') relating to such director nominations will be presented to the Nominating and Corporate Governance Committee for its consideration. Please see the section entitled 'Future Shareholder Proposals and Nominations' for information regarding the advance notice provisions applicable to stockholder director nominations set forth in our Bylaws.

Compensation Committee Interlocks and Insider Participation

During 2019, the members of the Compensation Committee were Messrs. Wunning, Gardner and Lance and Ms. Cooney, none of whom was, during the fiscal year, an officer or employee of the Company and none of whom has ever served as an officer of the Company. During 2019, none of our executive officers served as a director or member of the compensation committee (or other committee serving an equivalent function) of any other entity whose executive officers served on our Compensation Committee or the Board.

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Board Operations

As a Board, we believe that the practices we follow and the guidelines we adopt governing how we operate set an important tone at the top. Among other things we:

•meet regularly as a Board

•meet periodically in executive session of our independent directors

•have the authority to retain independent advisors

•enable directors to have access to management

•limit the number of public company boards on which directors may serve

•expect our directors as well as our executives to meet our stock ownership guidelines

•prohibit our directors and senior executives from taking specified hedging and pledging actions with Summit Materials stock

Executive Sessions and Communications with Directors

The Board's independent directors meet at regularly scheduled executive sessions without management present. Mr. Lance presides at executive sessions of independent directors.

Stockholders and other interested parties may communicate with the Board by writing to the Chief Legal Officer and Secretary, Summit Materials, Inc., 1550 Wynkoop Street, 3rd Floor, Denver, Colorado 80202. Written communications may be addressed to the Chairman of the Board, the chairperson of any of the Audit, Nominating and Corporate Governance, and Compensation Committees, or to the non-management or independent directors as a group. The Chief Legal Officer will forward such communications to the appropriate party.

Risk Oversight

The Board exercises direct oversight of strategic risks to the Company. The Audit Committee reviews guidelines and policies governing the process by which senior management assesses and manages the Company's exposure to risk, including the Company's major financial and operational risk exposures and the steps management takes to monitor and control such exposures. The Compensation Committee oversees risks relating to the Company's compensation policies and practices. Each committee charged with risk oversight reports to the Board on those matters.

With respect to cybersecurity risk oversight, our Board and our Audit Committee receive updates from our information technology team to assess the primary cybersecurity risks facing the Company and the measures the Company is taking to mitigate such risks. In addition to such updates, our Board and our Audit Committee receive updates from management as to changes to the Company's cybersecurity risk profile or significant newly identified risks.

In light of the importance of environmental matters to our shareholders, communities, customers, and employees, the full Board oversees environmental risk factors and receives regular updates from management and our sustainability team on the Company's environmental risk profile and key risk mitigating initiatives.

Code of Ethics

Our Code of Business Conduct and Ethics applies to all of our officers, directors and employees, including our principal executive officer, principal financial officer and principal accounting officer, or persons performing similar functions and is posted on our website. Our Code of Business Conduct and Ethics is a 'code of ethics,' as defined in Item 406(b) of Regulation S-K. We will make any legally required disclosures regarding amendments to, or waivers of, provisions of our Code of Business Conduct and Ethics on our website. The information contained on, or accessible from, our website is not part of this Proxy Statement by reference or otherwise.

Short Sales and Hedging Policy

Our Securities Trading Policy prohibits directors, officers, and employees ('Summit Materials Personnel'), family members of Summit Materials Personnel and trusts, corporations and other entities controlled by any such persons (collectively, 'Insiders') from trading in options, warrants, puts and calls or similar instruments on the Company's securities or selling such securities 'short' (i.e., selling stock that is not owned and borrowing the shares to make delivery). In addition, Summit Materials Personnel are prohibited under the Securities Trading Policy from engaging in any transactions (including variable forward contracts, equity swaps, collars and exchange funds) that are designed to hedge or offset any decrease in the market value of the Company's equity securities.

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Director Compensation

In 2019, all of the Company's non-employee directors received annual cash compensation of $100,000. The independent chairperson of the Board received an additional $150,000 in cash compensation. The respective chairpersons of the Audit Committee, Compensation Committee and Nominating and Corporate Governance Committee (unless such chairperson is also the chairperson of the Board) received an additional $15,000, $10,000 and $10,000, respectively. Directors who were not employed by us may also receive compensation, from time to time, for service on any special committees of the Board. We reimburse our directors for any reasonable expenses incurred by them in connection with services provided in such capacity.

In addition, during 2019, all of the Company's non-employee directors received an annual award of restricted stock units ('RSUs') valued at $125,000, which amount differs from the grant date fair value of the RSUs. A grant of 8,143 RSUs was made to each of Messrs. Lance, Cantie, Gardner, Murphy, and Wunning and Mss. Cooney, Ellerbusch, and Wade on February 28, 2019. The RSUs were granted under the Summit Materials, Inc. 2015 Omnibus Incentive Plan (the 'Omnibus Incentive Plan'), and the terms thereof are outlined in the table below. Further, the RSU awards are subject to the Company's incentive clawback policies, as in effect from time to time.

The Company's independent compensation consultant performs a comprehensive competitive total compensation review for the Company's non-employee directors every other year. The Company's total compensation structure and value for its directors are compared to its peer companies. The Company is currently competitively positioned. In the years the Company's independent compensation consultant does not perform a comprehensive review, they review broader U.S. market trends with the Compensation Committee.

Award Type
Vesting
Termination or Change in Control Provisions
RSUs Vest on the first anniversary of the date of grant

Death or Disability / By the Company Without Cause: Unvested portion will immediately vest.

Retirement(1) / Declining to Stand for Re-election to Our Board(2): Prorated portion immediately vests; settled at such time as would have been settled according to the original vesting schedule.

Change in Control: Accelerated only if not continued, converted, assumed or replaced by the Company or successor entity.

By the Company For Cause: Vested and unvested portions are forfeited.

(1)'Retirement' is defined in the director form of RSU award agreement as a director's resignation from service on our Board (other than due to death or disability or termination by the Company without cause), prior to the expiration of his or her term and on or after the date he or she attains age seventy.

(2)In each case, as of or after the regular annual meeting of stockholders for the calendar year which includes the date of grant.

Director Compensation Table

The table below summarizes the compensation paid to non-employee directors for the year ended December 28, 2019.

Name
Fees Earned or
Paid in Cash

Stock Awards(1)(2)
Total Compensation

Howard L. Lance

$250,000 $138,431 $388,431

Joseph S. Cantie

$100,000 $138,431 $238,431

Anne M. Cooney

$100,000 $138,431 $238,431

Susan A. Ellerbusch

$100,000 $138,431 $238,431

Ted A. Gardner

$110,000 $138,431 $248,431

John R. Murphy

$115,000 $138,431 $253,431

Anne K. Wade

$100,000 $138,431 $238,431

Steven H. Wunning

$110,000 $138,431 $248,431
(1)The amounts reported in the Stock Awards column reflect the aggregate grant date fair value of RSUs granted in fiscal 2019, computed in accordance with ASC 718, utilizing the assumptions discussed in Note 13, Stock-Based Compensation, to our audited consolidated financial statements included in the 2019 Annual Report. As of December 28, 2019, each of our non-employee directors held 8,143 RSUs.

(2)We did not make any option awards to directors in fiscal 2019. As of December 28, 2019, Messrs. Lance and Murphy held 246,611 and 10,220 time-vesting Leverage Restoration Options, respectively. Time-vesting Leverage Restoration Options held by our directors have the same vesting terms as those held by our NEOs and described in 'Narrative Disclosure to Summary Compensation Table and Grants of Plan-Based Awards Table-Pre-IPO Long-Term Incentive Awards (Value From Modifications to Eliminate Misalignment Post-IPO).' As of December 28, 2019, a limited liability company controlled by Mr. Gardner held 27,408 warrants, which became exercisable on March 17, 2016.

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OUR PAY

Our 'Say-on-Pay' Resolution Received 96% Support in 2019.

We believe our executive compensation structure is competitive, is aligned with current governance trends and contains stockholder-friendly features. For instance, in 2019, our Board adopted a Policy for Clawback of Incentive Compensation that applies to any current and former 'officer' of the Company and applies to annual cash bonuses and equity incentive compensation. Other stockholder-friendly features include the following:

What We Do (Best Practice)
What We Don't Do / Don't Allow

Enforce strict insider trading, anti-hedging and anti-pledging policies

Set stock ownership guidelines for executives and directors

Provide provisions for recoupment ('clawback') of equity incentive compensation in our award agreements and adopted a policy for clawback of annual cash bonuses and equity incentive compensation

Disclose performance goals for incentive programs

Set a maximum payout limit on our annual and long-term incentive programs for our NEOs

Incorporate change-in-control provisions that are consistent with market practice

Retain an independent compensation consultant that reports directly to the Compensation Committee

Perform an annual compensation program risk assessment to ensure that the Company's compensation policies and practices are not reasonably likely to have a material adverse effect on the Company

No change-in-control severance multiple in excess of three times salary and target bonus

No excise tax gross-ups upon a change in control

No re-pricing or cash buyout of underwater stock options

No enhanced retirement formulas

No guaranteed compensation

No market timing with granting of equity awards

Substantially no perquisites for our NEOs

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ITEM 2

NONBINDING ADVISORY VOTE ON THE
COMPENSATION OF OUR NEOs

Under the Dodd-Frank Wall Street Reform Consumer Protection Act (the 'Dodd-Frank Act') and Section 14A of the Exchange Act, our stockholders are entitled to vote to approve, on a nonbinding advisory basis, the compensation of our NEOs, as disclosed in this Proxy Statement in accordance with SEC rules. The compensation of our NEOs subject to the vote is disclosed in the Compensation Discussion and Analysis, the compensation tables, and the related narrative disclosure contained in this Proxy Statement. The compensation of our NEOs is designed to enable us to attract and retain talented and experienced executives to lead us successfully in a competitive environment, while ensuring that our executives remain incentivized to accomplish the Company's long-term business plan. As discussed in this Proxy Statement, the vast majority of each NEO's pay is at-risk and largely tied to challenging performance goals. We believe that our compensation policies and decisions are strongly aligned with our stockholders' interests.

The Board is asking our stockholders to indicate their support for the compensation of our NEOs as disclosed in this Proxy Statement by casting a nonbinding advisory vote 'FOR' the following resolution:

'RESOLVED, that the compensation paid to our NEOs, as disclosed pursuant to Item 402 of Regulation S-K, including the Compensation Discussion and Analysis, compensation tables, and narrative disclosure, is hereby APPROVED.'

Because the vote to approve the compensation of our NEOs is advisory, it is not binding on the Board or the Company. Nevertheless, the views expressed by our stockholders, whether through this vote or otherwise, are important to management and the Board and, accordingly, the Board and the Compensation Committee intend to consider the results of this vote in making determinations in the future regarding executive compensation arrangements, as a part of its robust compensation review and assessment process. Nonbinding advisory approval of this proposal requires the vote of the holders of a majority of the voting power of the shares present in person or represented by proxy and entitled to vote on the matter at the Annual Meeting.

THE BOARD RECOMMENDS A VOTE 'FOR' THE APPROVAL,
ON A NONBINDING ADVISORY BASIS, OF THE COMPENSATION
OF OUR NEOs, AS DISCLOSED IN THIS PROXY STATEMENT

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Compensation Committee Report

The Compensation Committee has reviewed and discussed the Compensation Discussion and Analysis with management. Based on this review and discussion, the Compensation Committee recommended to the Board that the Compensation Discussion and Analysis be included (incorporated by reference) in the Company's Annual Report on Form 10-K for the fiscal year ended December 28, 2019 and in this Proxy Statement.

Submitted by the Compensation Committee of the Board.

Steven H. Wunning, Chair
Anne M. Cooney
Ted A. Gardner
Howard L. Lance

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Compensation Discussion and Analysis-What We Paid

2019 Highlights

2019 was a turnaround year for the Company, following a challenging 2018. During 2019, we reported volume and price growth in all lines of business, led by our aggregates business, which delivered strong results due in part to strong performance from our East Segment. In addition, we were disciplined and selective in pursuing acquisitions while generating increased cash flow from operations, which enabled us to lower our leverage ratio. For the fiscal year 2019, Summit reported a higher total shareholder return than the S&P 500 and the S&P Construction Materials Index.

In 2019, our executive compensation structure consisted of four primary components: base salary; annual cash incentives; long-term equity incentives and traditional health/welfare plans. We previously eliminated substantially all perquisites in 2017.

Named Executive Officers

The following Compensation Discussion and Analysis ('CD&A') describes our 2019 executive compensation structure, earned by or paid to the following named executive officers ('NEOs'), followed by a discussion of the executive pay determination process. Our NEOs for 2019 were the following individuals:

Thomas W. Hill President and Chief Executive Officer
Brian J. Harris Executive Vice President and Chief Financial Officer
Michael J. Brady Executive Vice President and Chief Business Development Officer
Anne Lee Benedict Executive Vice President and Chief Legal Officer and Secretary
M. Shane Evans (1) Former Executive Vice President and West Division President
Karl H. Watson, Jr. (2) Former Executive Vice President and Chief Operating Officer
(1)On September 18, 2019, Mr. Evans informed the Company that while he would remain an employee of the Company, he would leave his role as the Company's Executive Vice President, West Division President, effective January 1, 2020.

(2)On June 6, 2019, Mr. Watson resigned from his role as Executive Vice President and Chief Operating Officer of the Company. Mr. Watson remained an employee of the Company through June 28, 2019.

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2019 Compensation at a Glance

Pay Element
Description
2019 Payout / Changes
Fixed Base Salary Fixed pay to recruit and retain executives Base salaries increased for each of our NEOs, except for Mr. Hill, by 3%, which was our standard merit increase for corporate employees in 2019, consistent with competitive market practices. Mr. Hill did not receive a base salary increase in 2019.
Variable Annual Cash Bonus Annual cash incentives based on rigorous financial, operational and personal goals measured over one year:

50%-60% EBITDA

10%-20% Operating Cash Flows

10% Safety

20% Personal Objectives

Each of our NEOs earned annual cash bonuses as set forth below in 'Elements of Pay: Annual Cash Incentives-2019 Actual Performance and Payouts.'
Long-Term Equity Incentives Long-term equity awards that align executives' interests with stockholders.

50% Performance Units

3-year relative total shareholder return ('TSR') compared to Materials and Capital Goods Companies (consisting of GICS industry groups 2010 and 1510) from the S&P 400 Midcap Index.

Capped at target if absolute TSR is negative.

Grants are based in the Company's Class A Common Stock.

During the performance period beginning January 1, 2017 and ending December 31, 2019, our Relative TSR ranked at the 36th percentile, resulting in a payout equal to 65.73% of target.
50% RSUs

Vest ratably over 3 years.

Grants are based in the Company's Class A Common Stock.

Other

Traditional Benefits Executive benefits are substantially similar to benefits offered to other employees. No change

Pay Mix and Magnitude

The Compensation Committee believes that a significant majority of both the CEO's and other NEOs' pay should be at risk and not guaranteed. Compensation is tied to challenging performance objectives and this is illustrated in our pay mix. A large percentage of total target compensation is at risk through long-term equity awards and annual cash incentive awards. These awards are linked to performance measures that correlate with long-term stockholder value creation. The amounts actually realized by our NEOs with respect to these awards depend on a variety of factors, including the level of attainment of the relevant performance goals and the extent of vesting of performance units and RSUs and the value of our stock when performance units and RSUs vest. The target values of long-term equity incentive awards used in the charts below differ from the compensation reported in the Summary Compensation Table due to the use of the grant date fair value in the Summary Compensation Table which is calculated in accordance with ASC 718, utilizing the assumptions discussed in our audited consolidated financial statements included in the 2019 Annual Report. The mix of total direct compensation at target for 2019 for our CEO and the average of our other NEOs is shown in the charts below.

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The Compensation Committee approved the following compensation targets for 2019:


Base Salary
Annual Bonus Target as % of Base Salary
Long-Term Incentive Target as % of Base Salary

Thomas W. Hill

$ 900,000 150 % 360 %

Brian J. Harris

$ 583,495 75 % 155 %

Michael J. Brady

$ 515,000 60 % 125 %

Anne Lee Benedict

$ 425,887 60 % 125 %

M. Shane Evans

$ 446,413 60 % 125 %

Karl H. Watson, Jr.

$ 566,500 75 % 155 %

Elements of Pay: Base Salary

The Compensation Committee determines base salaries for the NEOs and other executives based on a number of factors, including but not limited to, the Compensation Committee's understanding of executive pay practices, individual performance, Company performance and management recommendations (except with respect to the CEO).

Our financial performance in 2018 and 2019 affected how we paid our NEOs in 2019, including Mr. Hill not receiving a base salary increase for 2019 and the other NEOS only receiving 3% increases, which were our standard merit increase for corporate employees in 2019. In addition, these base salaries reflect a thorough review of competitive market data, internal alignment of total compensation opportunity, and are consistent with competitive market data provided by the Rewards Solutions Practice at Aon plc ('Aon').


2019 Base Salary
2018 to 2019 Increase

Thomas W. Hill

$ 900,000 0 %

Brian J. Harris

$ 583,495 3.0 %

Michael J. Brady

$ 515,000 3.0 %

Anne Lee Benedict

$ 425,887 3.0 %

M. Shane Evans

$ 446,413 3.0 %

Karl H. Watson, Jr.

$ 566,500 3.0 %

Elements of Pay: Annual Cash Incentives

2019 TARGET ANNUAL INCENTIVE AWARD OPPORTUNITIES

At the start of each fiscal year, the Board approves annual incentive compensation targets, as a percentage of base salary, based on competitive market data provided by Aon for our direct competitors and overall peer group, management's

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recommendations and other relevant factors. The 2019 annual incentive targets, as a percentage of base salary, for our NEOs were unchanged from 2018, as follows:


Target Bonus

Thomas W. Hill

150 %

Brian J. Harris

75 %

Michael J. Brady

60 %

Anne Lee Benedict

60 %

M. Shane Evans

60 %

Karl H. Watson, Jr.

75 %

2019 ANNUAL INCENTIVE METRICS

The metrics underlying our annual incentive were selected as the strongest indicators of our success. EBITDA and operating cash flow are among our most important financial measures, while safety goals ensure that we focus on sustainable performance. Personal objectives measure progress against key milestones that are important to long-term value creation. The Board has discretion to adjust the financial metrics to reflect merger, acquisition, divestiture and other non-routine activity during the fiscal year.

For corporate NEOs (Messrs. Hill, Harris, Brady, and Watson and Ms. Benedict), the performance metrics approved for fiscal 2019 were:

Metric

Definition/Notes
EBITDA Corporate earnings before interest, taxes, depreciation, depletion and amortization. Results are adjusted to exclude accretion, loss on debt financings, tax receivable agreement expense, income from discontinued operations and certain non-cash and non-operating items plus the EBITDA contribution of certain recent acquisitions and dispositions.
Operating Cash Flow Annual cash flow in excess of capital transactions and acquisitions.
Safety
Recordable Incident Rate (RIR) Any employee work-related injury that requires medical treatment and results in a positive diagnosis of an injury, a prescription or work restrictions (per OSHA), divided by hours worked.
Lost Time Incident Rate (LTIR) Same as RIR but only includes injuries that result in at least one full day away from work.
Preventable Incident Rate (PVIR) The number of preventable auto safety incidents, divided by miles driven.
Cost Per Man Hour (CPMH) Based on the total incurred insurance-company-posted claim reserves on 12/31 of a given year for all workers compensation, general liability and auto liability claims divided by the hours worked in that same calendar year.
Personal objectives Varies by individual. See 'Performance Targets and Payout Ranges-Personal Performance Goals.'

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For Mr. Evans, the approved performance metrics included (i) corporate EBITDA, (ii) West segment EBITDA, (iii) West segment operating cash flow, (iv) West segment safety and (v) personal objectives.

For 2019, performance metrics and weightings were as follows for our NEOs:


EBITDA
Operating Cash Flow
Safety(2)
Personal Objectives

Thomas W. Hill

50 % 20 % 10 % 20 %

Brian J. Harris

50 % 20 % 10 % 20 %

Michael J. Brady

50 % 20 % 10 % 20 %

Anne Lee Benedict

50 % 20 % 10 % 20 %

M. Shane Evans(1)

60 % 10 % 10 % 20 %

Karl H. Watson, Jr.

50 % 20 % 10 % 20 %
(1)Mr. Evans's (a) EBITDA metric consisted of 20% on corporate EBITDA and 40% on West Segment EBITDA, (b) operating cash flow metric was related to the West Segment and (c) safety metric related to the West Segment.

(2)Safety metrics included various metrics related to the frequency and severity of reported incidents. For 2019, the safety metrics (and the weightings assigned to each safety metric for each NEO) included RIR (4% total award payout), LTIR (1.5% total award payout), PVIR (3% total award payout), and CPMH (1.5% total award payout).

PERFORMANCE TARGETS AND PAYOUT RANGES

The achievement factor for each of the performance metrics was determined by multiplying the weight attributed to each performance metric by the applicable payout percentage for each metric. For corporate EBITDA, corporate cash flow, West Segment EBITDA, and West Segment operating cash flow, payout percentages were determined by calculating actual achievement against the target amount based on a pre-established scale.

Financial Performance

For corporate EBITDA, payout percentages for actual performance between the specified threshold level and 138% of target and between 138% of target and the maximum level, were adjusted on a linear basis. For corporate operating cash flow, payout percentages for actual performance between the specified threshold level and 100% of target and between 100% of target and the maximum level, were adjusted on a linear basis. The following table shows the payout percentages associated with various levels of achievement of corporate EBITDA and operating cash flow:

2019 Payout Percentage
25% (Threshold) 100% (Target) 138% 200% (Maximum)
2019 Corporate EBITDA
(Performance as a Percentage of Target)
90% 100% 105% 110%

0% (Threshold)
100% (Target)
125%
150% (Maximum)
2019 Corporate Operating Cash Flow
(Performance as a Percentage of Target)
90% 100% 105% 110%

Safety Performance Targets

The overall safety metric achievement factor equals the sum of each metric's payout percentage multiplied by its weighting. The maximum payout opportunities for the safety metrics is 150% of target. For the safety metrics, payout percentages for actual achievement between the specified threshold, target and maximum levels were adjusted on a linear basis. For the safety metrics below, the lower the result, the stronger the performance. All safety targets required year-over-year improvement in performance.

2019 Payout Percentage

0% (Threshold)
100% (Target)
150% (Maximum)

RIR-40% Safety

1.56 1.35 0.74

LTIR-15% Safety

0.12 0.10 0.00

PVIR-30% Safety

0.73 0.63 0.39

CPMH-15% Safety

0.18 0.17 0.10

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Personal Performance Goals

Personal performance goals may be focused on any combination of corporate, business-unit, or role-specific accomplishments or behaviors that focus executives on accomplishing our long-term business plan. The maximum payout under the Personal Performance Goal portion of the annual incentive is 150% of target.

Thomas W. Hill

Mr. Hill's personal performance goals included executing the Company's 2019 operating plan and developing a three (3) year comprehensive strategic plan. In addition, Mr. Hill was to complete and deliver to the Board an executive talent assessment and management succession plan.

Brian J. Harris

Mr. Harris's personal performance goals included recruiting a new head of investor relations and maintaining excellent relationships and communications with investors. In addition, Mr. Harris was to continue to develop and strengthen relationships with members of the Board and work with Mr. Watson to evaluate new enterprise resource planning software. Further, Mr. Harris was to optimize the Company's corporate debt structure and work with the Company's subsidiaries and regional finance leaders to drive improvements in forecasting, monthly management reporting and identifying risks and opportunities in the Company's business.

Karl H. Watson, Jr.

Mr. Watson's personal performance goals included achieving 2019 budget targets and advanced commercial processes. In addition, Mr. Watson was to continue to develop and strengthen relationships between the members of the senior leadership team and his personal relationships with members of the Board and presidents of the operating companies in the West Region. Further, Mr. Watson was to work with Mr. Brady on acquisition prospects and with Mr. Harris to evaluate new enterprise resource planning software.

Anne Lee Benedict

Ms. Lee Benedict's personal performance goals included driving further integration of the legal team as a business partner of the senior leadership team and maintaining and deepening relationships with the operating companies. In addition, Ms. Lee Benedict was to execute on a training program to the operating companies and corporate headquarters. Further, Ms. Lee Benedict was to refine management communications with the Board, evaluate the Company's governance posture and undertake a governance roadshow for the Company's investors. Finally, Ms. Lee Benedict was to identify and determine the feasibility of an outside law firm management tool.

Michael J. Brady

Mr. Brady's personal performance goals included leveraging the business development team's expertise and resources to support business performance across the Company. In addition, Mr. Brady was to develop a long-term acquisition pipeline while also leading the facilitation and sourcing of investments in 2019. Further, Mr. Brady's goals included measurements related to the financial performance of certain historical acquisitions. Finally, Mr. Brady was to develop and strengthen relationships between the members of the senior leadership team.

M. Shane Evans

Mr. Evans's personal performance goals included exceeding 2018 budget price increases and achieving certain safety goals. Mr. Evans's performance goals also included achieving budget targets in the West Region and driving the West Region's productivity growth. In addition, Mr. Evans was to facilitate increased effectiveness of the ready-mix concrete performance team in the West Region. Further, Mr. Evans was to continue to develop and strengthen relationships between the members of the senior leadership team and to partner with Mr. Watson to drive performance in the West Region.

Segment Goals

For Mr. Evans, West Segment EBITDA and West Segment Operating Cash Flow payout percentages were determined by calculating actual achievement against the target amount based on a pre-established scale. Payout percentage for actual performance between the specified threshold, target and maximum levels was adjusted on a linear basis. The following table

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shows the payout percentages associated with threshold, target and maximum achievement of West Segment EBITDA and West Segment Operating Cash Flow:

Payout Percentage
5% (Threshold) 100% (Target) 144% 200% (Maximum)

West Segment EBITDA (Percentage of Target)

85% 96% 100% 105%

West Segment Operating Cash Flow (Percentage of Target)

85% 96% 100% 105%

For Mr. Evans, the West Segment safety metric achievement factor equals the sum of each West Segment metric's payout percentage multiplied by its weighting. The maximum payout opportunities for the West Segment safety metrics is 150% of target. For the West Segment safety metrics, payout percentages for actual achievement between the specified threshold, target and maximum levels were adjusted on a linear basis. For the safety metrics below, the lower the result, the stronger the performance.

2019 Payout Percentage
0% (Threshold) 100% (Target) 150% (Maximum)

West Segment RIR-40% Safety

1.61 1.40 0.74

West Segment LTIR-15% Safety

0.20 0.12 0.00

West Segment PVIR-30% Safety

0.71 0.62 0.38

West Segment CPMH-15% Safety

0.217 0.20 0.10

2019 ACTUAL PERFORMANCE AND PAYOUTS

Actual results for the 2019 annual incentive plan were certified by the Compensation Committee, as follows, based on the performance goals and funding scales approved in the first quarter of 2019:

Initial Target Adjusted Target(1) Actual
Results(2)
Payout Percentage Weighted
Payout
Corporate EBITDA ($ Millions) $ 471.0 NA $461.5 85 % 42.5 %
Corporate Operating Cash Flow
($ Millions)
$ 252.4 $236.9 $275.7 140 % 28.0 %
West Segment EBITDA
($ Millions)
$ 228.7 NA $205.0 48 % 19.2 %
West Segment Operating Cash Flow
($ Millions)
$ 133.3 NA $126.7 91 % 9.1 %
(1)Initial targets for Corporate Operating Cash Flow were adjusted in 2019 to reflect unplanned capital expenditures that did not contribute to EBITDA in 2019.

(2)See 'Reconciliation of Non-GAAP Measures to GAAP' on Annex A.

The payout percentages for the safety metrics were as follows: corporate safety was 69% of target, resulting in a weighted payout of 6.9% for each NEO other than Mr. Evans; West Segment safety for Mr. Evans was 71% of target, resulting in a weighted payout of 7.1%.

Actual annual cash incentive awards are calculated by multiplying each NEO's actual base salary by his or her target award potential, which was then adjusted by an overall achievement factor based on the combined weighted achievement of the components described above, including an evaluation of each NEO's personal objectives.


2019 Base Salary
Target Incentive as a
Percentage of Salary

Actual Incentive Earned
as a Percentage of Salary

Annual Cash
Incentive Earned

Thomas W. Hill

$ 900,000 150 % 148 % $1,328,738

Brian J. Harris

$ 583,495 75 % 76 % $442,982

Michael J. Brady

$ 515,000 60 % 60 % $310,313

Anne Lee Benedict

$ 425,887 60 % 61 % $259,685

M. Shane Evans

$ 446,413 60 % 43 % $191,243

Karl H. Watson, Jr.(1)

$ 566,500 75 % 0 % $0
(1)On June 6, 2019, Mr. Watson resigned from his role as Executive Vice President and Chief Operating Officer of the Company. Mr. Watson remained an employee of the Company through June 28, 2019.

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Long-Term Equity Incentives

LONG-TERM INCENTIVES

Our equity incentives for NEOs in 2019 consisted of a balance of performance units (50%) and RSUs (50%). The Compensation Committee uses competitive market data from our annual total compensation study to assist with targeted long-term incentive value. In addition, the Compensation Committee considers individual performance, potential future contributions to our business, internal equity and management's recommendations except in the case of the CEO.

Award Type
Weighting
Vesting
Value Tied To
Performance Units 50% Vest at the end of a 3-year period in an amount based on the level of performance achieved Company three-year TSR ranking to the companies in the peer group (defined as the S&P 400 Midcap Materials and Capital Goods Companies)
RSUs 50% Vest over 3 years in equal annual installments on each anniversary of the grant date Stock price performance

Performance Units Granted in 2019

The 2019 performance units focus our executives on the long-term performance of the Company relative to industry peers. The 2019 performance units vest at the end of a three-year performance period, based on our TSR ranking relative to a TSR peer group ('Relative TSR') defined as the S&P 400 Midcap Materials and Capital Goods Companies. This peer group is separate and distinct from the peer group used to evaluate and set NEO compensation levels discussed under '-Compensation Decision Process-Role of Peer Companies and Competitive Market Data.' The Relative TSR peer group represents a broader array (approximately 125 companies for TSR performance grants in 2017 and approximately 65 companies for TSR performance grants in 2018 and 2019) of industry peers competing for stockholders and investors.

The performance period for the performance units granted in February 2019 began on January 1, 2019 and ends on December 31, 2021 and are earned based on performance against the target below. Earned amounts will be interpolated on a straight-line basis for performance between the stated percentiles.

Level of Achievement
Below Threshold Threshold Target Maximum Cap (if applicable)
Relative TSR Position < 25th percentile 25th percentile 50th percentile 75th percentile Capped at 100% if Company TSR is negative over performance period, regardless of ranking
Achievement Percentage 0% 50% of target 100% target 200% of target

See '-Treatment of Long-Term Incentive Awards Upon Termination or Change in Control' for a description of the potential vesting of the NEOs' equity awards that may occur in connection with certain termination events and a change in control.

For 2019, the Compensation Committee set the target pay levels and made the grants set forth in the table below.


2019 Target Long-Term
Incentive as % of Base Salary

2019 Target Long-Term
Incentive(1)

Performance Units Granted
(#)

Restricted Stock Units Granted
(#)

Thomas W. Hill

360% $ 3,240,000 105,537 105,537

Brian J. Harris

155% $ 904,417 29,460 29,460

Michael J. Brady

125% $ 643,750 20,969 20,969

Anne Lee Benedict

125% $ 532,359 17,341 17,341

M. Shane Evans

125% $ 558,016 18,176 18,176

Karl H. Watson, Jr.

155% $ 878,075 28,602 28,602
(1)The target award values shown vary from the values listed in the 2019 Grants of Plan Based Awards Table for two reasons. First, the 2019 Grants of Plan Based Awards Table uses the Monte Carlo valuation method, which determines the accounting expense for our performance units because they are based on Relative TSR. This generated an expense value approximately 54% higher than the actual value on the grant date. However, we do not believe the Monte Carlo accounting model is appropriate for purposes of setting total compensation opportunity. Second, to mitigate the potential impact of short-term stock price swings on our equity grants, we use the 20-day average closing stock price immediately preceding the grant date to determine the grant size, rather than the closing stock price on the actual grant date as shown in the 2019 Grants of Plan Based Awards Table.

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Performance Units Earned for the Performance Period 2017-2019

In 2017, we granted performance units to our NEOs (except for Mr. Watson) that were subject to similar performance conditions as the performance units granted in 2019. Specifically, the performance units were scheduled to vest after a three-year performance period beginning January 1, 2017 and ending December 31, 2019 based on our Relative TSR to companies in the S&P Building & Construction Select Industry Index, using beginning and ending stock prices based on the trailing 20-day average closing price. During the performance period, our Relative TSR ranked at the 36th percentile, resulting in a payout equal to 65.73% of target.

Retirement, Perquisites, and Other Benefits

We have a tax-qualified contributory retirement plan established to qualify as a deferred salary arrangement under Section 401(k) of the Internal Revenue Code of 1986, as amended (the 'Code'). The plan covers all U.S. employees, including our NEOs, who are limited to their annual tax deferred contribution limit as allowed by the Internal Revenue Service (the 'IRS'). We provide for matching contributions to the plan, including 100% of pre-tax employee contributions, up to 4% of eligible compensation. Employer contributions vest immediately.

The Company also offers the members of a select group of management or highly compensated employees, including the NEOs, the opportunity to supplement their retirement savings through the Summit Materials Deferred Compensation Plan (the 'DCP'). An eligible participant in the DCP may elect to defer up to 50% of such participant's base salary compensation and up to 100% of such participant's designated discretionary bonus award compensation and annual incentive award compensation. The DCP also permits Company-provided credits to participants' accounts, but no such credits are currently being made. Additional information about the DCP is reflected in '-2019 Non-Qualified Deferred Compensation' below.

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Compensation Discussion and Analysis-How We Paid

Our Compensation Philosophy

Our executive compensation program is intended to attract, motivate and retain executive officers and to align the interests of our executive officers with stockholders' interests.

The Board's objectives for our program include, but are not limited to, the following:

Say-on-Pay Votes

In 2019, the Compensation Committee considered the outcome of the stockholder advisory vote on 2018 executive compensation when making decisions relating to the compensation of our NEOs and our executive compensation program and policies. Our stockholders voted at our 2019 annual meeting, in a nonbinding advisory vote, on the 2018 compensation paid to our NEOs. Our stockholders overwhelmingly (96%) approved the compensation of our NEOs. Based on the level of support, the Compensation Committee determined that stockholders generally support our compensation practices. The Compensation Committee intends to continue to consider the views of our stockholders when designing, reviewing and administering the Company's compensation programs and policies.

Compensation Decision Process

Role of the
Compensation
Committee
The Compensation Committee is responsible to our Board for oversight of our executive compensation program. The Compensation Committee is responsible for the review and approval of all aspects of our program.

Among its duties, the Compensation Committee is responsible for:

Assessing competitive market data from Aon, our independent compensation consultant (the 'Independent Compensation Consultant')

Reviewing each NEO's performance in conjunction with competitive market data and, accordingly, approving compensation recommendations including, but not limited to, base salary, annual bonus, long-term incentives, and benefits/perquisites

Considering, recommending and approving incentive plan goals, achievement levels, and program structure

Incorporating meaningful input from our stockholders, if applicable

Role of Management For each NEO excluding himself, our CEO recommends to the Compensation Committee compensation levels for NEOs based on a review of market data and individual performance. The Compensation Committee reviews and discusses all recommendations prior to approval, then submits all recommendations to the Board for approval.

For the CEO, during executive session without the CEO present, the Compensation Committee is solely responsible for assessing performance and making compensation recommendations to the Board for approval. Management does not make compensation-related recommendations for the CEO.

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Role of the
Independent
Compensation
Consultant
In 2019, the Compensation Committee retained the Independent Compensation Consultant in accordance with the Compensation Committee's charter. The Independent Compensation Consultant reports directly to the Compensation Committee. The Compensation Committee retains sole authority to hire or terminate the Independent Compensation Consultant, approve its fees, determine the nature and scope of services and evaluate the Independent Compensation Consultant's performance.

A representative of the Independent Compensation Consultant attends Compensation Committee meetings, as requested, and communicates with the Compensation Committee chair between meetings. The Compensation Committee makes all final decisions and recommendations.

The Independent Compensation Consultant's roles include, but are not limited to, the following:

Advising the Compensation Committee on executive compensation trends and regulatory developments;

Developing a peer group of companies for determining competitive compensation amounts and practices;

Providing a total compensation study for executives against peer companies;

Providing advice to the Compensation Committee on governance best practices, as well as any other areas of concern or risk; and

Reviewing and commenting on proxy disclosure items, including the CD&A.

The Compensation Committee has assessed the independence of the Independent Compensation Consultant, considering all relevant factors, including those set forth in Rule 10C-1(b)(4)(i) through (vi) under the Exchange Act. Based on this review, the Compensation Committee concluded that there are no conflicts of interest raised by the work performed by the Independent Compensation Consultant and that the Independent Compensation Consultant is independent.

Role of Peer
Companies and
Competitive
Market Data
In the Fall of 2018, to assist with 2019 compensation decisions, the Independent Compensation Consultant performed a competitive pay study. To develop competitive market values for the NEOs, the Independent Compensation Consultant developed, and the Compensation Committee approved, a peer group of 17 companies, which were the same companies used in the prior year.

The peer group development criteria included:

Industry: Companies in the building products or construction materials industries

Company size: Approximately 0.4x to 3x times our annual revenues

ISS: Companies considered by Institutional Shareholder Services ('ISS') to be the Company's compensation peers and used in ISS' annual report regarding the Company

Peers of Peers: Companies used in the peer groups of potential peer companies

Consistency: Companies contained in the peer group in the prior year

The approved peer group had annual revenues which ranged from approximately $867 million to $4.4 billion, with median annual revenue of approximately $1.8 billion. For our Fall 2018 total compensation study, our 2018 annual revenue was estimated at approximately $2.2 billion. The Independent Compensation Consultant developed size-adjusted market values (regression analysis) for each position using our annual revenue.

The 50th percentile for total compensation is a key reference point for the Compensation Committee; however, the Compensation Committee also considers other factors, including, experience, performance and expected future contributions. For positions where peer company proxy data was not available, the Independent Compensation Consultant utilized published and private compensation survey sources.

PEER GROUP

Armstrong World Industries, Inc.

Boise Cascade Company

Compass Minerals International, Inc.

CONSOL Energy Inc.

Dycom Industries, Inc.

Eagle Materials Inc.

Gibraltar Industries, Inc.

Granite Construction Inc.

Louisiana-Pacific Corp.

Martin Marietta Materials, Inc.

Masonite International Corporation

NCI Building Systems Inc.

Quanex Building Products Corp.

Simpson Manufacturing Company

US Concrete Inc.

USG Corp.

Vulcan Materials Company

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TIMING OF COMPENSATION DECISIONS

Pay recommendations for our executives, including the NEOs, are typically made by the Compensation Committee at its first scheduled meeting of the fiscal year, typically held in February around the same time we report our fourth quarter and year-end financial results for the preceding fiscal year and provide our financial guidance for the upcoming year (the 'first meeting'). This timing allows the Compensation Committee to have a complete financial performance picture prior to making compensation decisions.

Decisions with respect to prior year performance, as well as annual equity awards, base salary increases and target performance levels for the current year are typically made at the first meeting. Any equity awards recommended by the Compensation Committee at this meeting are reviewed by the Board and, if approved, are dated on or within a few days of the date of the Board meeting held later that day or the following day. As such, the Compensation Committee does not time the grants of equity incentives to the release of material non-public information.

The exceptions are grants to executives who are promoted or hired from outside the Company during the year, and discretionary grants made throughout the year for retention and extraordinary purposes. These executives may receive compensation changes or equity grants effective or dated, as applicable, as of the date of their promotion, hiring date, or other Board approval date.

DETERMINATION OF CEO COMPENSATION

At the first meeting, in executive session without the CEO present, the Compensation Committee also reviews and evaluates CEO performance, and determines performance achievement levels, for the prior fiscal year. The Compensation Committee also reviews competitive compensation data from the peer group companies. The Compensation Committee typically approves, or presents, pay recommendations for the CEO to the Board, excluding the CEO, for approval. If applicable, during executive session, the Board conducts its own review and evaluation of the CEO's performance taking into consideration the recommendations of the Compensation Committee.

EQUITY PLAN

The Company maintains the Omnibus Incentive Plan which allows for grants of equity-based awards in the form of stock options, stock appreciation rights, restricted stock and RSUs, performance units, undivided fractional limited partnership interests in Summit Holdings and other stock-based awards.

Governance of Executive Compensation

STOCK OWNERSHIP GUIDELINES

We have established stock ownership guidelines for our CEO, officers reporting to the CEO, and directors. The approved guidelines are as follows:

• CEO: 6x base salary

• Officers reporting to the CEO: 2.5x base salary

• Directors: 3x annual cash retainer

Participants are expected to comply with the ownership requirements within five years of the later of (a) December 12, 2015 and (b) an appointment to a qualified position. Once the ownership requirements have been satisfied, future declines in share price will not affect compliance so long as the participant holds the number of equity interests he or she had at the time he or she achieved the expected ownership level. As of February 14, 2020, all of our executive officers have met or exceeded the ownership expectations under the guidelines.

The following components satisfy the ownership guidelines: Equity interests owned directly or indirectly (e.g., by or with a spouse or held in trust for the individual or one or more family members of the individual), equity interests, including limited partnership interests (the 'LP Units') and unvested RSUs, held in qualified or nonqualified savings, profit sharing, or deferred compensation accounts, value of in-the-money spread of shares underlying vested but unexercised stock options and value of in-the-money spread of shares underlying vested but unexercised warrants. At least annually, the Compensation Committee monitors participants' compliance with these guidelines.

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INCENTIVE COMPENSATION RECOUPMENT ('INCENTIVE CLAWBACK') POLICIES

In 2019, our Board adopted a Policy for Clawback of Incentive Compensation (the 'Policy') because it believes that it is in the best interests of the Company and its stockholders to create and maintain a culture that emphasizes integrity and accountability and that reinforces the Company's pay-for-performance compensation philosophy. This policy applies to any current and former 'officer' of the Company, as such term is defined under Rule 16a-1(f) of the Exchange Act (the 'Covered Executives'). The Policy applies to annual cash bonuses and equity incentive compensation ('Incentive Compensation'). Under the Policy, if the Company is required to prepare an accounting restatement of the reported financial results of the Company or any of its segments due to (a) the material non-compliance of the Company with any financial reporting requirement (unless due to a change in accounting policy or applicable law) and (b) intentional misconduct by a Covered Executive, then the Compensation Committee may require any Covered Executive to repay to the Company any 'Excess Compensation.' Excess Compensation means that part of the Incentive Compensation received by a Covered Executive during the one-year period preceding the publication of the restated financial statement that the Committee determines was in excess of the amount that such Covered Executive would have received had such Incentive Compensation been calculated based on the financial results reported in the restated financial statement.

In addition, each of the RSU, stock option and performance unit award agreements under the Omnibus Incentive Plan generally provides that if a restrictive covenant violation occurs or the Company discovers after a termination of employment or services that grounds existed for 'cause' (as defined in the Omnibus Incentive Plan) at the time thereof, then the participant shall be required, in addition to any other remedy available (on a non-exclusive basis), to pay to the Company, within ten business days of the Company's request to the participant therefor, an amount equal to the aggregate after-tax proceeds (taking into account all amounts of tax that would be recoverable upon a claim of loss for payment of such proceeds in the year of repayment) the participant received upon the sale or other disposition of, or distributions in respect of, the equity award thereunder and any shares issued in respect thereof (minus, in the case of options, the aggregate cost (if any) of the shares). Without limiting the foregoing, all awards are subject to reduction, cancellation, forfeiture or recoupment to the extent necessary to comply with applicable law. Our policy will be updated to comply with the SEC's final regulations as part of the Dodd-Frank Act.

Compensation Risk Assessment

Our governance policies and compensation structure are not reasonably likely to have a material adverse effect on the Company. The Independent Compensation Consultant and management delivered a compensation risk assessment report to the Compensation Committee in 2019. The following features of our program mitigate risk:

The Compensation Committee consults with the Independent Compensation Consultant to assist with annual compensation decisions



The Compensation Committee approves the annual incentive plan's financial goals at the start of the fiscal year, and approves the performance achievement level and final payments earned at the end of the fiscal year



The Compensation Committee benchmarks total compensation opportunity for executive positions using multiple survey sources and has discretion over payout calculations and oversight of compensation plans for our executives



We utilize a mix of cash and equity variable incentive programs, with a balanced mix of RSUs and performance units, which are subject to multi-year vesting



Our performance units payout opportunities are capped at 200% of the target total opportunity



We utilize competitive change-in-control severance programs to help ensure executives continue to work towards our stockholders' best interests in light of potential employment uncertainty



Executive officers are subject to minimum stock ownership guidelines



Incentive clawback policies that permit the Company to recoup annual cash bonuses and equity incentive compensation paid on the basis of financial results that are subsequently restated

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Compensation Tables

Summary Compensation Table

The following table sets forth the compensation of our NEOs for the fiscal years ended 2019, 2018 and 2017, and their respective titles as of December 28, 2019.

Name and Principal Position
Year
Salary
($)

Stock Awards
($)(1)

Option Awards
($)

Non-Equity
Incentive Plan
Compensation
($)(2)

All Other
Compensation
($)(3)

Total
($)

Thomas W. Hill 2019 900,000 4,559,198 - 1,328,738 24,493 6,812,429
President and Chief 2018 900,000 3,750,312 - - 23,693 4,674,005
Executive Officer, Director 2017 826,956 1,735,523 620,771 1,275,480 16,140 4,474,870
Brian J. Harris 2019 583,495 1,272,672 - 442,982 15,964 2,315,113
Executive Vice President, Chief Financial Officer 2018 566,500 1,521,907 - - 13,694 2,102,101
2017 550,000 650,591 232,706 450,326 10,400 1,894,023
Michael J. Brady 2019 515,000 905,861 - 310,313 14,748 1,745,922
Executive Vice President, 2018 500,000 769,241 - - 13,292 1,282,533
Chief Business Development Officer 2017 425,000 324,336 116,014 283,764 11,029 1,160,143
Anne Lee Benedict 2019 425,887 749,131 - 259,685 13,073 1,447,776
Executive Vice President, Chief Legal Officer, and Secretary
M. Shane Evans(4) 2019 446,413 785,203 - 191,243 16,682 1,439,541
Executive Vice President, 2018 433,411 654,555 - - 15,859 1,103,825
West Division President 2017 420,787 321,112 114,863 323,669 14,056 1,194,487
Karl H. Watson, Jr.(5) 2019 283,250 1,235,606(6) - - 12,361 1,531,217
Former Executive Vice President, Chief Operating Officer 2018 550,000 2,036,565 - - 11,332 2,597,897
(1)The amounts reported in the Stock Awards column for 2019 reflect the aggregate grant date fair value of stock awards granted in fiscal 2019, calculated in accordance with ASC 718, utilizing the assumptions discussed in Note 13, Stock-Based Compensation, to our audited consolidated financial statements included in the 2019 Annual Report. The fiscal 2019 awards consist of time-vesting RSUs and performance units. As the performance units vest according to Relative TSR, they are subject to market conditions, and not performance conditions, as defined under ASC 718, and therefore have no maximum grant date fair values that differ from the grant date fair values presented in the table.

(2)Reflects non-equity incentive plan compensation awards for services rendered during the fiscal year presented. For more information, see 'Compensation Discussion and Analysis-Compensation Elements-Annual Cash Incentives.'

(3)All Other Compensation includes the following items for 2019: (a) amounts contributed by Summit LLC under the Summit Materials, LLC Retirement Plan and (b) payments for term life and/or disability insurance. Amounts contributed to the Summit Materials, LLC Retirement Plan are matching contributions up to 4% of eligible compensation subject to IRS limits and totaled $11,200 for each of the NEOs in 2019. Matching contributions are immediately vested. For more information, see 'Compensation Discussion and Analysis-Compensation Elements-Retirement, Perquisites, and Other Benefits.' Payments for term life and/or disability insurance in 2019 were as follows: Mr. Hill, $13,293; Mr. Harris, $3,564; Mr. Brady, $3,548; Ms. Benedict, $673; Mr. Evans, $5,482; and Mr. Watson, $1,161.

(4)On September 18, 2019, Mr. Evans informed the Company that while he would remain an employee of the Company, he would leave his role as the Company's Executive Vice President, West Division President, effective January 1, 2020.

(5)On June 6, 2019, Mr. Watson resigned from his role as Executive Vice President and Chief Operating Officer of the Company. To facilitate an orderly transition, Mr. Watson remained an employee of the Company through June 28, 2019.

(6)Pursuant to the award agreements between the Company and Mr. Watson, upon Mr. Watson's departure on June 28, 2019 he forfeited all of his unvested equity awards, which included all stock awards granted to him in 2019.

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2019 Grants of Plan-Based Awards

The following table provides supplemental information relating to grants of plan-based awards to help explain information provided above in our Summary Compensation Table.










All Other
Stock
Awards:
Number of
Shares
of Stock
or Units
(#)(3)





Estimated Possible Payouts under
Non-Equity Incentive
Plan Awards(1)
Estimated Future Payouts
under Equity Incentive
Plan Awards(2)
Grant
Date Fair
Value of
Stock
Awards
($)(4)

Name
Award Type
Grant
Date

Threshold
($)

Target
($)

Maximum
($)

Threshold
(#)

Target
(#)

Maximum
(#)

Thomas W. Hill Annual Cash Incentive - 16,200 1,350,000 2,497,500 - - - - -
Performance Units 2/28/2019 - - - 52,769 105,537 211,074 - 2,765,069
RSUs 2/28/2019 - - - - - - 105,537 1,794,129
Brian J. Harris Annual Cash Incentive - 5,251 437,621 809,599 - - - - -
Performance Units 2/28/2019 - - - 14,730 29,460 58,920 - 771,852
RSUs 2/28/2019 - - - - - - 29,460 500,820
Michael J. Brady Annual Cash Incentive - 4,635 309,000 714,563 - - - - -
Performance Units 2/28/2019 - - - 10,485 20,969 41,938 - 549,388
RSUs 2/28/2019 - - - - - - 20,969 356,473
Anne Lee Benedict Annual Cash Incentive - 3,066 255,532 472,735 - - - - -
Performance Units 2/28/2019 - - - 8,671 17,341 34,682 - 454,334
RSUs 2/28/2019 - - - - - - 17,341 294,797
M. Shane Evans Annual Cash Incentive - 3,214 267,848 495,518 - - - - -
Performance Units 2/28/2019 - - - 9,088 18,176 36,352 - 476,211
RSUs 2/28/2019 - - - - - - 18,176 308,992
Karl H. Watson, Jr.(5) Annual Cash Incentive - 5,098 424,875 786,019 - - - - -
Performance Units 2/28/2019 - - - 14,301 28,602 57,204 - 749,372
RSUs 2/28/2019 - - - - - - 28,602 486,234
(1)Reflects the possible payouts of cash incentive compensation under the Non-Equity Incentive Plan. Amounts reported in the 'Threshold' column assume that there is no payout under the EBITDA, operating cash flow, or personal objectives components of the annual cash incentive program and that each NEO only earns the minimum payout for the one safety metric that has been assigned the lowest weighting. The actual amounts paid are described in the 'Non-Equity Incentive Plan Compensation' column of the 'Summary Compensation Table.'

(2)Reflects the performance units granted in 2019, which have a three-year performance period ending December 31, 2021, and vest based on Relative TSR. Threshold assumes that 50% of the total performance units awarded vest and maximum assumes that 200% of the total performance units awarded vest.

(3)Reflects the RSUs granted in 2019.

(4)Represents the grant date fair value of the performance units and RSUs granted in 2019 with respect to the NEOs. The assumptions applied in determining the fair value of the awards are discussed in Note 13, Stock-Based Compensation, to our audited consolidated financial statements included in the 2019 Annual Report.

(5)Pursuant to the award agreements between the Company and Mr. Watson, upon Mr. Watson's departure on June 28, 2019 he forfeited all of his unvested equity awards, which included all stock awards granted to him in 2019.

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Narrative Disclosure to Summary Compensation
Table and Grants of Plan-Based Awards Table

Employment Arrangements

Messrs. Hill and Harris and Ms. Lee Benedict each have employment agreements and Mr. Brady has a signed offer of employment. Their employment agreements and offers of employment provide for base salary subject to annual adjustment by the Board, an annual incentive award, participation in Company-sponsored broad-based and executive benefit plans and such other compensation as may be approved by the Board. In connection with implementing the Executive Severance Plan (the 'Severance Plan'), Messrs. Hill and Harris and Ms. Lee Benedict waived the provisions in their employment agreements that would have applied under the conditions set forth in the Severance Plan, other than any provisions in their employment agreements which were intended to survive the termination of such employment agreements.

Pre-IPO Long-Term Incentive Awards (Value From Modifications to Eliminate Misalignment Post-IPO)

Prior to the Company's initial public offering ('IPO') in March 2015, the equity-based long-term incentive program consisted of Class D interests. In connection with the Company's IPO in March 2015, the limited partnership agreement of Summit Holdings was amended and restated to, among other things, modify its capital structure by creating LP Units (the 'Reclassification'). Immediately following the Reclassification, the LP Units were reclassified from previously issued Class A-1, Class B-1, Class C, Class D-1 and Class D-2 interests.

In addition, in substitution for part of the economic benefit of the Class C and Class D interests that was not reflected in the conversion of such interests to LP Units, warrants were issued to holders of Class C interests to purchase shares of Class A Common Stock, and options were issued to holders of Class D interests to purchase shares of Class A Common Stock ('Leverage Restoration Options') under the Omnibus Incentive Plan.

All outstanding equity grants associated with the Reclassification and subsequent modifications are summarized in the table titled 'Outstanding Equity Awards at 2019 Fiscal Year-End.'

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Outstanding Equity Awards at 2019 Fiscal Year-End

A summary of the outstanding equity awards for each NEO as of December 28, 2019 is as follows in the below table. Upon Mr. Watson's departure date of June 28, 2019, Mr. Watson forfeited all of his unvested equity awards.

Option Awards Stock Awards
Name Grant Date Number of
Securities
Underlying
Unexercised
Options (#)
Exercisable
Number of
Securities
Underlying
Unexercised
Options (#)
Unexercisable
Equity Incentive
Plan Awards:
Number of
Securities
Underlying
Unexercised
Unearned
Options (#)
Option
Exercise
Price ($)
Option
Expiration
Date(1)
Number of
Shares or
Units of
Stock That
Have Not
Vested (#)
Market
Value of
Shares or
Units of
Stock That
Have Not
Vested
($)(2)
Equity Incentive
Plan Awards:
Number of
Unearned Shares,
Units or Other
Rights That Have
Not Vested (#)
Equity Incentive
Plan Awards:
Market or
Payout Value of
Unearned
Shares, Units or
Other Rights
That Have Not
Vested ($)(2)
Thomas W.
Hill
3/11/2015 536,111(3) - - 18.00 3/11/2025 - - - -
3/11/2015 29,463(4) - - 18.00 3/11/2025 - - - -
2/24/2016 23,979(5) - - 17.07 2/24/2026 - - - -
2/28/2017 34,174(5) 17,087(5) - 23.89 2/28/2027 - - - -
2/28/2017 - - - - - 10,252(6) 244,407 - -
2/28/2017 - - - - - 20,829(7) 496,563 - -
2/28/2018 - - - - - 34,505(6) 822,599 - -
2/28/2018 - - - - - - - 51,757(8) 1,233,887
2/28/2019 - - - - - 105,537(6) 2,516,002 - -
2/28/2019 - - - - - - - 211,074(9) 5,032,004
Brian J.
Harris
2/28/2017 12,811(5) 6,405(5) - 23.89 2/28/2027 - - - -
2/28/2017 - - - - - 3,843(6) 91,617 - -
2/28/2017 - - - - - 7,808(7) 186,143 - -
2/28/2018 - - - - - 9,352(6) 222,952 - -
2/28/2018 - - - - - - - 14,027(8) 334,404
2/28/2019 - - - - - 29,460(6) 702,326 - -
2/28/2019 - - - - - - - 58,920(9) 1,404,653
Michael J.
Brady
3/11/2015 407,072(3) - - 18.00 3/11/2025 - - - -
3/11/2015 6,852(4) - - 18.00 3/11/2025 - - - -
2/24/2016 13,498(5) - - 17.07 2/24/2026 - - - -
2/28/2017 6,387(5) 3,193(5) - 23.89 2/28/2027 - - - -
2/28/2017 - - - - - 1,916(6) 45,677 - -
2/28/2017 - - - - - 3,893(7) 92,809 - -
2/28/2018 - - - - - 6,656(6) 158,679 - -
2/28/2018 - - - - - - - 9,984(8) 238,019
2/28/2019 - - - - - 20,969(6) 499,901 - -
2/28/2019 - - - - - - - 41,938(9) 999,802
Anne Lee
Benedict
2/28/2017 5,975(5) 2,987(5) - 23.89 2/28/2027 - - - -
2/28/2017 - - - - - 1,792(6) 42,721 - -
2/28/2017 - - - - - 3,641(7) 86,253 - -
2/28/2018 - - - - - 5,504(6) 131,215 - -
2/28/2018 - - - - - - - 8,256(8) 196,823
2/28/2019 - - - - - 17,341(6) 413,409 - -
2/28/2019 - - - - - - - 34,682(9) 826,819
M. Shane
Evans
2/28/2017 6,323(5) 3,162(5) - 23.89 2/28/2027 - - - -
2/28/2017 - - - - - 1,897(6) 45,224 - -
2/28/2017 - - - - - 3,854(7) 91,879 - -
2/28/2018 - - - - - 5,770(6) 137,557 - -
2/28/2018 - - - - - - - 8,654(8) 206,311
2/28/2019 - - - - - 18,176(6) 433,316 - -
2/28/2019 - - - - - - - 36,352(9) 866,632
(1)Reflects the expiration date of the Leverage Restoration Options and stock options which is ten years from the date of grant. The warrants expire on the tenth anniversary of the pricing of the Company's IPO. See 'Narrative Disclosure to Summary Compensation Table and Grants of Plan Based Awards Table-Pre IPO Long-Term Incentive Awards' for a description of these equity awards.

(2)Amounts reported are based on the closing price of our Class A Common Stock on December 27, 2019 ($23.84), the last trading day of the fiscal year.

(3)Reflects Leverage Restoration Options that vested over four years at a rate of 25% of the award on each of the first four anniversaries of the Reclassification, subject to the employee's continued employment through the applicable vesting date.

(4)Reflects warrants issued in connection with the Reclassification as described in 'Narrative Disclosure to Summary Compensation Table and Grants of Plan-Based Awards Table-Pre-IPO Long-Term Incentive Awards (Value From Modifications to Eliminate Misalignment Post-IPO).' The warrants became exercisable on March 17, 2016.

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(5)Reflects stock options which vest over three years in equal annual installments on the anniversary of the grant date.

(6)Reflects RSUs which vest over three years in equal annual installments on the anniversary of the grant date.

(7)Reflects performance units which vested according to Relative TSR at the end of a three-year performance period.

(8)Reflects performance units which vest according to Relative TSR at the end of a three-year performance period. In the table above, the number and market value of units that vest based on Relative TSR reflect threshold performance, because actual performance during the performance periods that have elapsed through December 28, 2019 was below threshold. The actual numbers of shares that will be distributed with respect to the 2018 performance units are not yet determinable.

(9)Reflects performance units which vest according to Relative TSR at the end of a three-year performance period. In the table above, the number and market value of units that vest based on Relative TSR reflect maximum performance, because actual performance during the performance periods that have elapsed through December 28, 2019 were above target performance. The actual numbers of shares that will be distributed with respect to the 2019 performance units are not yet determinable.

2019 Option Exercises and Stock Vested

The following table provides information regarding the amounts recognized by our NEOs upon the exercise of stock options and the vesting of stock awards during 2019.

Option Awards Stock Awards

Name

Number
of Shares
Acquired on
Exercise (#)(1)
Value
Realized on
Exercise ($)(2)
Number
of Shares
Acquired on
Vesting (#)(3)
Value
Realized on
Vesting ($)(4)

Thomas W. Hill

- - 62,715 1,126,827

Brian J. Harris

261,155 1,630,690 22,003 396,949

Michael J. Brady

- - 11,836 212,558

Anne Lee Benedict

42,904 243,956 10,831 194,804

M. Shane Evans

253,838 1,441,327 11,465 206,222

Karl H. Watson, Jr.

- - 21,388 310,768
(1)Represents Leverage Restoration Options and stock options.

(2)The value realized on exercise is based on the closing market price of our Class A common stock on the applicable exercise date minus the exercise price of the option.

(3)Represents time-vesting RSUs and performance units.

(4)The value realized on vesting is based on the closing market price of our Class A common stock on the applicable vesting date.

2019 Non-Qualified Deferred Compensation

The following table provides information regarding contributions, earnings and balances for our NEOs with respect to our DCP, the only defined contribution or other plan that provides for the deferral of compensation on a basis that is not tax-qualified.

Name
Executive
Contributions
in Last FY(1) ($)

Registrant
Contributions
in Last FY ($)

Aggregate
Earnings in
Last FY(2) ($)

Aggregate
Withdrawals/
Distributions ($)

Aggregate
Balance at
Last FYE(3) ($)

Thomas W. Hill

- - 140,380 - 674,149

Brian J. Harris

291,748 - 238,955 - 1,262,253
(1)These amounts are also reported in the 'Salary' column for 2019 in the 'Summary Compensation Table.'

(2)Amounts in this column are not reported as compensation for fiscal 2019 in the 'Summary Compensation Table' since they do not reflect above-market or preferential earnings.

(3)Mr. Hill commenced participation in the DCP in fiscal 2017 and $273,504 was previously reported in the 'Salary' column for 2017 and $255,096 was previously reported in the 'Salary' column for 2018 with respect to Mr. Hill in the 'Summary Compensation Table.' Mr. Harris commenced participation in the DCP in fiscal 2016 and $275,000 was previously reported with respect to Mr. Harris in the 'Salary' column for 2017 and $283,250 was previously reported in the 'Salary' column for 2018 in the 'Summary Compensation Table.'

Pursuant to the DCP, an eligible participant may elect to defer up to 50% of such participant's base salary compensation (in 5% increments) and up to 100% of such participant's designated discretionary bonus award compensation and annual incentive award compensation (in 5% increments). Deferral elections are generally made by participants prior to the close of the taxable year preceding the taxable year for which the applicable compensation is earned. The DCP also permits Company-provided credits to participants' accounts, but no such credits are currently being made. Participants are permitted to make individual investment elections that will determine the rate of return on their deferral amounts under the DCP and may change their investment elections at any time. Deferrals are only deemed to be invested in the investment options selected. Participants have no ownership interest in any of the funds as investment elections are used solely to measure the amounts of investment earnings or losses that will be credited or debited to the participants' accounts on the Company's books and records. Investment funds are valued each day that the NYSE is open for trading. Participant deferrals under the DCP and the earnings thereon are always 100% vested.

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The table below shows the funds in which our NEOs invested during 2019, and their rate of return from January 1, 2019 through December 31, 2019.

Name of Investment Fund
Rate of Return %

Alger Capital Appreciation Z

33.62%

American Beacon Mid-Cap Value Instl

26.55%

American Century Real Estate R6

31.14%

American Funds Income Fund of Amer R6

19.27%

American Funds New World R6

28.03%

Columbia Dividend Income Y

28.31%

Fidelity Advisor International Discv Z

27.66%

Janus Henderson Triton N

28.60%

Pioneer Bond K

9.35%

T. Rowe Price New Era

16.88%

Templeton Global Bond R6

1.01%

Undiscovered Managers Behavioral Val R6

23.34%

Vanguard 500 Index Investor

31.46%

Vanguard Market Neutral Inv

-9.57%

Vanguard Mid Cap Index Investor

31.03%

Vanguard Mid-Cap Growth Index Investor

33.86%

Vanguard Small Cap Index Fund

27.37%

Vanguard Target Retirement 2015 Inv

14.81%

Vanguard Target Retirement 2025 Inv

19.63%

Vanguard Target Retirement 2035 Inv

22.44%

Vanguard Target Retirement 2045 Inv

24.94%

Western Asset High Yield IS

15.09%

A DCP participant may elect, at the time of such participant's deferral elections, to receive benefit distributions upon (i) separation from service with the Company or (ii) following the earlier of (a) a specified date that occurs no earlier than at least three years from the end of the calendar year in which the deferred compensation is credited or (b) separation from service with the Company. Additionally, a DCP participant may elect, at the time of such participant's deferral elections, to receive benefit distributions in the form of (i) a single lump sum payment or (ii) for distributions following retirement, annual installments with an installment term of between two and 15 years. A participant may elect to change the benefit distribution date and/or form under certain circumstances specified in the DCP. In addition, in the event of certain unforeseeable emergencies, a participant may apply for immediate distribution in an amount necessary to satisfy such financial hardship and the tax liability attributable to such distribution. In the event of a participant's death or disability, the entire value of such participant's account will be distributed in a single lump sum.

Potential Payments Upon Termination or Change in Control

EXECUTIVE SEVERANCE PLAN

The Board, upon the recommendation of the Compensation Committee, adopted the Severance Plan in December 2017, which provides severance benefits to certain executive officers of the Company and its affiliates in the event that an eligible employee experiences a termination of employment by the Company without 'cause' (and other than due to death or disability) or by the employee as a result of a 'constructive termination' (as such terms are defined in the Severance Plan) (each, a 'Qualifying Termination'). In the event that a Qualifying Termination occurs during the two-year period beginning on the date of a change in control (each such termination, a 'Qualifying Change in Control Termination'), the Severance Plan provides enhanced severance benefits. In connection with implementing the Severance Plan, all participants in the Severance Plan waived the provisions of any applicable employment agreement that would have applied under the conditions set forth under the Severance Plan, other than any provisions in such employment agreements which were intended to survive the termination of such employment agreement.

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Each participant in the Severance Plan (a 'Participant') is designated as a Tier 1 Participant or Tier 2 Participant. Tier 1 Participants are limited to the Chief Executive Officer. Tier 2 Participants are limited to Executive Vice Presidents. Accordingly, Mr. Hill is a Tier 1 Participant and Messrs. Brady, Evans and Harris and Ms. Lee Benedict are each Tier 2 Participants.

In the event of a Qualifying Termination, Participants are provided with the following payments and benefits:

•a pro-rata payment representing the amount otherwise payable under the annual bonus program for the fiscal year in which termination of the Participant's employment occurs, based on actual performance and payable concurrently with cash bonus payments to other employees (but in all events on or about March 15 of the immediately following fiscal year) (a 'Pro-Rata Bonus'), and to the extent not previously paid, the amount otherwise payable under the annual bonus program for the immediately preceding fiscal year, payable concurrently with cash bonus payments to other employees (a 'Prior Year Bonus');

•a cash payment of (i) for a Tier 1 Participant, 2.5 times the Participant's annual base salary, payable over a period of 30 months, and (ii) for a Tier 2 Participant, 2 times the Participant's annual base salary, payable over a period of 24 months; and

•a cash payment in an amount equal to the total amount of the monthly COBRA insurance premiums for participation in the life, health, dental and disability benefit programs of the Company in which the Participant participated as of the date of termination, payable monthly in accordance with the Company's payroll practices, (i) for a Tier 1 Participant, for up to 30 months, and (ii) for a Tier 2 Participant, for up to 24 months (the 'COBRA Benefits').

In the event of a Qualifying Change in Control Termination, Participants are provided with the following payments and benefits:

•a Pro-Rata Bonus, and, if applicable, a Prior Year Bonus;

•a cash payment of (i) for a Tier 1 Participant, 2.5 times the sum of the Participant's annual base salary and target annual bonus, and (ii) for a Tier 2 Participant, 2 times the sum of the Participant's annual base salary and target annual bonus, in each case of (i) and (ii), payable in a lump sum no later than the 60th day following the date of termination; and

•the COBRA Benefits.

The payments and benefits provided under the Severance Plan are subject to each Participant's execution and delivery of a release of claims and each Participant's compliance with non-competition, non-disparagement, non-solicitation and confidentiality covenants applicable pursuant to each Participant's Participation Notice and Agreement under the Severance Plan. The non-disparagement and confidentiality covenants each have an indefinite term and the non-competition and non-solicitation covenants each have a term of 12 months following the Participant's date of termination (18 months for Mr. Hill). Additionally, the Severance Plan provides that if a Participant is subject to an excise tax under Section 4999 of the Code, then the payments and benefits the Participant receives may be reduced so that the excise tax does not apply; however, such reduction will only occur if it results in the receipt of a greater after-tax severance than would otherwise be provided.

DEPARTURE OF KARL H. WATSON, JR.

On June 6, 2019, Mr. Watson resigned from his role as Executive Vice President and Chief Operating Officer of the Company. Mr. Watson remained an employee of the Company through June 28, 2019. Pursuant to the Executive Severance Plan and the award agreements between the Company and Mr. Watson, upon Mr. Watson's departure he was not entitled to any severance, and he forfeited all of his unvested equity awards. In addition, pursuant to his offer letter, Mr. Watson repaid his one-time cash sign-on bonus of $300,000 in connection with his resignation.

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Treatment of Long-Term Incentive Awards Upon Termination or Change in Control

Each of the RSUs and performance units granted in 2019 is subject to restrictive covenants related to post-employment (i) employee, client and consultant non-solicitation and (ii) non-competition, in each case for 12 months following any termination of employment and indefinite covenants covering confidentiality and non-disparagement (participant only). Further, the equity awards and all proceeds therefrom are generally subject to the Company's incentive clawback policies, as in effect from time to time, to the extent the participant is a director or 'officer' as defined under Rule 16a-1(f) of the Exchange Act. Additional provisions regarding the treatment of the equity awards upon a termination of employment are outlined in the table below.

Award Type Termination or Change in Control Provisions
Stock Options

Death or Disability: Unvested portion will immediately vest; vested stock options remain exercisable for one year thereafter.(1)

Retirement(2): Unvested portion will continue to vest according to the original vesting schedule; vested stock options remain exercisable for five years after the later of (i) the termination date and (ii) the date the option becomes vested and exercisable.

Constructive Termination(3) / By the Company Without Cause: Prorated portion of the number of options that would otherwise vest on the next applicable vesting date will immediately vest(4); vested stock options remain exercisable for three months thereafter.

Change in Control: Accelerated only if (i) not continued, converted, assumed, or replaced by the Company or successor entity or (ii) employment is terminated by the Company or successor entity without cause or by the participant as a result of a 'constructive termination' during the two-year period following a change in control; vested stock options remain exercisable for three months thereafter.

By the Company For Cause / by Participant When Grounds for Cause Exist: Vested and unvested portions are forfeited.

RSUs

Death or Disability: Unvested portion will immediately vest.

Retirement: Unvested portion will continue to vest according to the original vesting schedule.

Constructive Termination / By the Company Without Cause: Prorated portion of the number of RSUs that would otherwise vest on the next applicable vesting date will immediately vest.

Change in Control: Accelerated only if (i) not continued, converted, assumed, or replaced by the Company or successor entity or (ii) employment is terminated by the Company or successor entity without cause or by the participant as a result of a 'constructive termination' during the two-year period following a change in control.

By the Company For Cause: Vested and unvested portions are forfeited.

Performance Units

Death or Disability(5): Prorated portion will vest at the end of the performance period, based on actual performance.

Retirement: Prorated portion will vest at the end of the performance period, based on actual performance.

Constructive Termination / By the Company Without Cause: Prorated portion will vest at the end of the performance period, based on actual performance.

Change in Control: (i) Full vesting at target only if not continued, converted, assumed, or replaced by the Company or successor entity and (ii) pro-rata vesting at target if employment is terminated by the Company or successor entity without cause or by the participant as a result of a 'constructive termination' during the two-year period following a change in control.

By the Company For Cause: Vested and unvested portions are forfeited.

(1)Stock options do not remain exercisable past the original expiration date. In addition, the exercisability period expires immediately upon the occurrence of a 'restrictive covenant violation' (as defined in the award agreement).

(2)'Retirement' is generally defined in the equity awards as termination of employment, other than for cause or while grounds for cause exist, and other than due to the participant's death or disability, following the date on which (i) the participant attains age 62 and (ii) the number of completed years of employment with the Company and its affiliates is at least five. For stock options and RSUs, continuation of vesting after termination of employment is subject to the non-occurrence of a 'restrictive covenant violation.'

(3)'Constructive termination' is generally defined in the equity awards as (i) having the meaning set forth in any employment agreement entered into by and between the participant and the Company or an affiliate, or (ii) if no such agreement exists, any of the following, without the participant's prior written consent: (a) a material reduction in base salary or, to the extent applicable, target bonus opportunity (other than in connection with an across-the-board reduction in compensation of similarly-situated employees of, on an individual-by-individual basis, less than 10%), (b) a material diminution of authority, duties, or

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responsibilities, (c) a relocation of the participant's primary place of business by more than 50 miles from its then-current location, or (d) any material breach by the Company of any written agreement relating to the participant's compensation (including any equity awards). 'Constructive termination' provisions are limited to the Chief Executive Officer and his direct reports and other Section 16 officers.

(4)Prorated based on the number of days in the applicable year or in the performance period, as applicable, that have elapsed prior to termination of employment.

(5)Vesting of the prorated portion at the end of the performance period is subject to the non-occurrence of a 'restrictive covenant violation,' in the case of each applicable termination scenario.

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TERMINATION BENEFITS TABLE

The following table describes the potential payments and benefits under the Company's Severance Plan and equity award agreements to which the NEOs (other than Mr. Watson, see '-Departure of Karl H. Watson, Jr.') would have been entitled assuming an eligible termination of employment or change in control occurred on December 27, 2019, the last business day of fiscal 2019. A description of the provisions governing such payments under our agreements and any material conditions or obligations applicable to the receipt of payments are described above under 'Executive Severance Plan' and 'Treatment of Long-Term Incentive Awards Upon Termination or Change in Control.'

The amounts shown in the table do not include payments and benefits to the extent they are provided generally to all salaried employees upon termination of employment and do not discriminate in scope, terms or operation in favor of the NEOs. These include accrued but unpaid salary and distributions of vested plan balances under our 401(k) savings plans.

Acceleration of Long-Term Incentive Awards

Named Executive Officer

Cash
Severance
Payment
($)(1)
Pro-rata
Bonus
($)(2)
COBRA
Benefit
($)(3)
RSUs
($)
Stock
Options
($)(*)
Performance
Units
($)(4)
Total
($)

Thomas W. Hill

Qualifying Termination

2,250,000 - 64,589 1,245,312 - - 3,559,901

Qualifying Change in Control Termination

5,625,000 - 64,589 3,583,009 - 4,505,355(6) 13,777,953

Change in Control

- - - 3,583,009 - 4,505,355(6) 8,088,364

Termination Upon Death or Disability(5)

- - - 3,583,009 - - 3,583,009

Brian J. Harris

Qualifying Termination

1,166,990 - 42,743 364,335 - - 1,574,068

Qualifying Change in Control Termination

2,042,233 - 42,743 1,016,895 - 1,319,925(6) 4,421,796

Change in Control

- - - 1,016,895 - 1,319,925(6) 2,336,820

Termination Upon Death or Disability(5)

- - - 1,016,895 - - 1,016,895

Michael J. Brady

Qualifying Termination

1,030,000 - 51,671 243,042 - - 1,324,713

Qualifying Change in Control Termination

1,648,000 - 51,671 704,257 - 879,100 (6) 3,283,028

Change in Control

- - - 704,257 - 879,100(6) 1,583,357

Termination Upon Death or Disability(5)

- - - 704,257 - - 704,257

Anne Lee Benedict

Qualifying Termination

851,774 - 29,244 205,110 - - 1,086,128

Qualifying Change in Control Termination

1,362,838 - 29,244 587,346 - 742,306(6) 2,721,734

Change in Control

- - - 587,346 - 742,306(6) 1,329,652

Termination Upon Death or Disability(5)

- - - 587,346 - - 587,346

M. Shane Evans

Qualifying Termination

892,826 - 51,671 215,368 - - 1,159,865

Qualifying Change in Control Termination

1,428,522 - 51,671 616,097 - 779,401(6) 2,875,691

Change in Control

- - - 616,097 - 779,401(6) 1,395,498

Termination Upon Death or Disability(5)

- - - 616,097 - - 616,097
(*)As of December 27, 2019, the closing price of one share of the Company's Class A common stock was below the exercise price for all outstanding stock options that were not yet vested. Therefore, the values presented are zero.

(1)In the event of a 'constructive termination' or termination by the Company without 'cause' (each term as defined in the Severance Plan), the cash severance payment includes the following:

• Mr. Hill-a cash payment of 2.5 times his annual base salary, payable over a period of 30 months.

• Messrs. Evans, Harris and Brady and Ms. Lee Benedict-a cash payment of 2 times each NEO's annual base salary, payable over a period of 24 months.

In the event of a constructive termination or termination by the Company without cause during the two-year period beginning on the date of a change in control of the Company, the cash severance payment includes the following:


• Mr. Hill-a cash payment payable in a lump sum no later than the 60th day following the date of termination equal to 2.5 times the sum of his annual base salary and target annual bonus for 2019.

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• Messrs. Evans, Harris and Brady and Ms. Lee Benedict-a cash payment payable in a lump sum no later than the 60th day following the date of termination equal to 2 times the sum of each NEOs annual base salary and target annual bonus for 2019.

(2)Pro-rata bonus represents the amount otherwise payable under the annual bonus program for the fiscal year in which termination of the Participant's employment occurs, based on actual performance and payable concurrently with cash bonus payments to other employees (but in all events prior to March 15 of the immediately following fiscal year).

(3)COBRA benefit represents a cash payment in an amount equal to the total amount of the monthly COBRA insurance premiums for participation in the life, health, dental and disability benefit programs of the Company in which the NEO participated as of the date of termination, payable monthly in accordance with the Company's payroll practices. The terms of these payments are the following:

• Mr. Hill-for up to 30 months.

• Messrs. Evans, Harris and Brady and Ms. Lee Benedict-for up to 24 months.

(4)In the event of a Qualifying Change in Control Termination or a Change in Control, the amount reported assumes performance units are not continued, converted, assumed, or replaced by the Company or successor entity and therefore reflects full vesting at target.

(5)In the event of the death of Mr. Hill, in addition to amounts reported in the table above, Mr. Hill will receive benefits from third-party payors under our employer-paid premium life insurance plans. If such benefits were triggered for Mr. Hill on December 27, 2019 under our life insurance plans the legally designated beneficiary(ies) of Mr. Hill would have received $1,500,000.

(6)As indicated under note (4) above, the amount reported includes the target value of the 2017 Performance Units, which were subsequently earned as of December 31, 2019, the end of the performance period, at an amount equal to 65.73% of target. The target value of 2017 Performance Units for each NEO was $755,466 (Mr. Hill), $283,195 (Mr. Harris), $141,180 (Mr. Brady), $131,215 (Ms. Lee Benedict), and $139,774 (Mr. Evans) at December 27, 2019.

CEO Pay Ratio

The CEO pay ratio figures below are a reasonable estimate calculated in a manner consistent with Item 402(u) of Regulation S-K under the Exchange Act.

In 2017, we identified our median employee using our global employee population as of December 5, 2017. There was no significant change in our employee population or compensation arrangement in 2018 or 2019, and there have been no changes in the median employee's circumstances during 2018 or 2019, that we reasonably believe would result in a significant change in our pay ratio disclosure. Accordingly, we have used the same median employee we identified in 2017 for purposes of calculating our CEO pay ratio for 2019. We identified our median employee for the 2017 pay ratio analysis using the methodology and the material assumptions, adjustments, and estimates described below.

To determine our median employee pay in 2017, we chose taxable wages as our consistently applied compensation measure. We then calculated an annual taxable wage for each employee, annualizing pay for those full-time or part-time permanent employees who commenced work during 2017 or who were on leave for a portion of 2017. We used a valid statistical sampling method to identify the group of employees within a 5% range of the estimated median level of taxable wages for our employee population. The historical compensation of this group was then analyzed to identify a median employee whose annual total compensation was reasonably representative of the median annual total compensation in respect of 2017 and was also reasonably likely to remain representative of the median in future years.

We calculated the median employee's annual total compensation for 2019 in accordance with the requirements of the Summary Compensation Table. For 2019, the median employee's annual total compensation was $61,969 and the annual total compensation of our CEO was $6,812,429. Accordingly, for 2019, the ratio of CEO pay to median employee pay was 110:1.

This pay ratio is a reasonable estimate calculated in a manner consistent with SEC rules and the methodology described above. The SEC rules for identifying the median compensated employee and calculating the pay ratio based on such employee's annual total compensation allow companies to adopt a variety of methodologies, to apply certain exclusions, and to make reasonable estimates and assumptions that reflect their compensation practices. As such, the pay ratio reported by other companies may not be comparable to the pay ratio reported above, as other companies may have different employment and compensation practices and may utilize different methodologies, exclusions, estimates and assumptions in calculating their own pay ratios.

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OUR AUDITORS


ITEM 3
RATIFICATION OF APPOINTMENT OF
KPMG LLP

Under the rules and regulations of the SEC, the NYSE and the Public Company Accounting Oversight Board (the 'PCAOB'), the Audit Committee is directly responsible for the appointment, compensation, retention and oversight of our independent registered public accounting firm. In addition, the Audit Committee considers the independence of our independent registered public accounting firm and participates in the selection of the independent registered public accounting firm's lead engagement partner. The Audit Committee has appointed, and, as a matter of good corporate governance, is requesting ratification by our stockholders of the appointment of, the registered public accounting firm of KPMG to serve as independent registered public accounting firm for the fiscal year ending January 2, 2021. KPMG has served as our independent registered public accounting firm since 2012.

The Board and the Audit Committee believe that the continued retention of KPMG as the Company's independent registered public accounting firm is in the best interests of the Company and its stockholders. If stockholders do not ratify the selection of KPMG, the Audit Committee will evaluate the stockholder vote when considering the selection of a registered public accounting firm for the audit engagement for the 2020 fiscal year. In addition, even if stockholders ratify the selection of KPMG as independent registered public accounting firm, the Audit Committee may nevertheless periodically request proposals from the major registered public accounting firms and as a result of such process may select KPMG or another registered public accounting firm as our independent registered public accounting firm.

THE BOARD RECOMMENDS A VOTE 'FOR' RATIFICATION
OF THE APPOINTMENT OF KPMG AS OUR INDEPENDENT
REGISTERED PUBLIC ACCOUNTING FIRM FOR THE FISCAL
YEAR ENDING JANUARY 2, 2021.

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INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

Representatives of KPMG are expected to attend the Annual Meeting and will have an opportunity to make a statement and to respond to appropriate questions from stockholders.

Consistent with SEC and PCAOB requirements regarding auditor independence, the Audit Committee has responsibility for appointing, setting compensation for and overseeing the work of, the independent registered public accounting firm. In recognition of this responsibility, the Audit Committee has established a policy to pre-approve all audit and permissible non-audit services provided by the independent registered public accounting firm.

Prior to engagement of the independent registered public accounting firm for the next year's audit, management will submit to the Audit Committee for approval a list of services and related fees expected to be rendered during that year within each of the following four categories of services:

•Audit services include audit work performed on the financial statements and internal control over financial reporting, as well as work that generally only the independent registered public accounting firm can reasonably be expected to provide, including comfort letters, statutory audits and discussions surrounding the proper application of financial accounting and/or reporting standards.

•Audit-Related services are for assurance and related services that are traditionally performed by the independent registered public accounting firm, including due diligence related to mergers and acquisitions, employee benefit plan audits and special procedures required to meet certain regulatory requirements.

•Tax services include all services, except those services specifically related to the financial statements, performed by the independent registered public accounting firm's tax personnel, including tax analysis; assisting with coordination of execution of tax-related activities, primarily in the area of corporate development; supporting other tax-related regulatory requirements; tax planning; and tax compliance and reporting.

•All Other services are those services not captured in the Audit, Audit-Related or Tax categories.

Prior to engagement, the Audit Committee pre-approves independent registered public accounting firm services within each category and the fees of each category are budgeted. The Audit Committee requires the independent registered public accounting firm and management to report actual fees versus the budget periodically throughout the year by category of service. During the year, circumstances may arise when it may become necessary to engage the independent registered public accounting firm for additional services not contemplated in the original pre-approval categories. In those instances, the Audit Committee requires specific pre-approval before engaging the independent registered public accounting firm.

The Audit Committee may delegate pre-approval authority to one or more of its members. The member to whom such authority is delegated must report, for informational purposes only, any pre-approval decisions to the Audit Committee at its next scheduled meeting. All of the services in the table below were pre-approved by the Audit Committee.

(in thousands)
2019
2018

Audit Fees(1)

$ 4,046 $ 3,974

Tax Fees

- -

Audit-Related Fees

- -

All Other Fees

- -

Total

$ 4,046 $ 3,974
(1)Represents the aggregate fees billed for professional services by KPMG for the audit of our financial statements, reviews of our quarterly financial statements and services associated with other SEC filings, including registration statements. Fees related to registration statements totaled $98,130 in 2019 and $0 in 2018.

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AUDIT COMMITTEE REPORT

The Audit Committee reviews the Company's financial reporting process on behalf of the Board. Management has the primary responsibility for establishing and maintaining adequate internal control over financial reporting, for preparing the financial statements, and for the reporting process. The Audit Committee members do not serve as professional accountants or auditors, and their functions are not intended to duplicate or to certify the activities of management and the independent registered public accounting firm. The Company's independent registered public accounting firm is engaged to audit and report on the conformity of the Company's financial statements to accounting principles generally accepted in the United States and the effectiveness of the Company's internal control over financial reporting.

In this context, the Audit Committee reviewed and discussed with management and the independent registered public accounting firm the audited financial statements for the year ended December 28, 2019 (the 'Audited Financial Statements'), management's assessment of the effectiveness of the Company's internal control over financial reporting, and the independent registered public accounting firm's evaluation of the Company's system of internal control over financial reporting. The Audit Committee has discussed with the independent registered public accounting firm the matters required to be discussed by Public Company Accounting Oversight Board (the 'PCAOB') Auditing Standard No. 1301, Communications with Audit Committees. In addition, the Audit Committee has received the written disclosures and the letter from the independent registered public accounting firm required by applicable requirements of the PCAOB regarding the independent registered public accounting firm's communications with the Audit Committee concerning independence, and has discussed with the independent registered public accounting firm its independence.

Based upon the reviews and discussions referred to above, the Audit Committee recommended to the Board that the Audited Financial Statements be included in the Company's Annual Report on Form 10-K for the year ended December 28, 2019, for filing with the Securities and Exchange Commission.

The Audit Committee



John R. Murphy, Chair
Joseph S. Cantie
Anne K. Wade
Susan A. Ellerbusch

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CERTAIN RELATIONSHIPS AND RELATED PERSON TRANSACTIONS

Exchange Agreement

In connection with the IPO, we entered into an Exchange Agreement with the holders of LP Units pursuant to which each holder of LP Units (and certain permitted transferees thereof) may, subject to the terms of the Exchange Agreement, exchange their LP Units for shares of Class A Common Stock on a one-for-one basis, subject to customary conversion rate adjustments for stock splits, stock dividends and reclassifications. The Exchange Agreement also provides that a holder of LP Units will not have the right to exchange LP Units if the Company determines that such exchange would be prohibited by law or regulation or would violate other agreements with the Company or its subsidiaries to which such holder may be subject. The Company may impose additional restrictions on exchange that it determines to be necessary or advisable so that Summit Holdings is not treated as a 'publicly traded partnership' for U.S. federal income tax purposes. As a holder exchanges LP Units for shares of Class A Common Stock, the number of LP Units held by the Company is correspondingly increased as it acquires the exchanged LP Units. In accordance with the Exchange Agreement, any holder who surrenders all of its LP Units for exchange must concurrently surrender all shares of Class B Common Stock held by it (including fractions thereof) to the Company.

Tax Receivable Agreement

In connection with the IPO, we entered into a tax receivable agreement with the holders of LP Units that provides for the payment to exchanging holders of LP Units of 85% of the benefits, if any, that the Company is deemed to realize as a result of the increases in tax basis resulting from exchanges of LP Units and certain other tax benefits related to entering into the tax receivable agreement, including tax benefits attributable to payments under the tax receivable agreement. Certain current and former holders of LP Units, who include certain of our executive officers and directors, are expected to receive payments under the tax receivable agreement in the future. The increases in tax basis as a result of an exchange of LP Units for shares of Class A Common Stock, as well as the amount and timing of any payments under the tax receivable agreement, are difficult to accurately estimate as they will vary depending upon a number of factors, including:

the timing of exchanges-for instance, the increase in any tax deductions will vary depending on the fair market value, which may fluctuate over time, of the depreciable or amortizable assets of Summit Holdings at the time of each exchange;

the price of shares of our Class A Common Stock at the time of the exchange-the increase in any tax deductions, as well as the tax basis increase in other assets, of Summit Holdings, is directly proportional to the price of shares of our Class A Common Stock at the time of the exchange;

the extent to which such exchanges are taxable-if an exchange is not taxable for any reason, increased deductions will not be available;

the amount and timing of our income-the Company is required to pay 85% of the cash tax savings as and when realized, if any. If the Company does not have taxable income, the Company is not required (absent a change of control or circumstances requiring an early termination payment) to make payments under the tax receivable agreement for that taxable year because no cash tax savings will have been realized. However, any tax attributes that do not result in realized benefits in a given tax year will likely generate tax attributes that may be utilized to generate benefits in previous or future tax years. The utilization of such tax attributes will result in cash tax savings that will result in payments under the tax receivable agreement; and

the effective tax rate-the benefit that the Company realizes is dependent on the tax rate in effect at the time taxable income is generated.

We anticipate funding payments under the tax receivable agreement from cash flows from operations, available cash and available borrowings under our senior secured revolving credit facilities. As of December 28, 2019, we had accrued $327 million as a tax receivable agreement liability. The tax receivable agreement liability is a long-term liability as no additional payments are expected in the next twelve months.

In addition, the tax receivable agreement provides that upon certain changes of control, the Company's (or its successor's) obligations would be based on certain assumptions, including that the Company would have sufficient taxable income to fully utilize the deductions arising from the tax deductions, tax basis and other tax attributes subject to the tax receivable agreement.

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With respect to our obligations under the tax receivable agreement relating to previously exchanged or acquired LP Units and certain net operating losses, we would be required to make a payment equal to the present value (at a discount rate equal to one year LIBOR plus 100 basis points) of the anticipated future tax benefits determined using assumptions (ii) through (v) of the following paragraph.

Furthermore, the Company may elect to terminate the tax receivable agreement early by making an immediate payment equal to the present value of the anticipated future cash tax savings. In determining such anticipated future cash tax savings, the tax receivable agreement includes several assumptions, including that (i) any LP Units that have not been exchanged are deemed exchanged for the market value of the shares of Class A Common Stock at the time of termination, (ii) the Company will have sufficient taxable income in each future taxable year to fully realize all potential tax savings, (iii) the Company will have sufficient taxable income to fully utilize any remaining net operating losses subject to the tax receivable agreement on a straight line basis over the shorter of the statutory expiration period for such net operating losses or the five-year period after the early termination or change of control, (iv) the tax rates for future years will be those specified in the law as in effect at the time of termination and (v) certain non-amortizable assets are deemed disposed of within specified time periods. In addition, the present value of such anticipated future cash tax savings are discounted at a rate equal to LIBOR plus 100 basis points.

Under the terms of the tax receivable agreement, the Company can terminate the tax receivable agreement at any time, which would trigger a cash payment to the pre-IPO owners. Based upon a $23.84 per share price of our Class A common stock, the closing price of our stock on December 27, 2019 (the last business day of our fiscal year) and a contractually defined discount rate of 3.00%, the Company estimates that if it were to exercise its right to terminate the tax receivable agreement, the aggregate amount required to settle the tax receivable agreement would be approximately $289 million.

Summit Materials Holdings L.P. Amended and Restated Limited Partnership Agreement

The Company holds LP Units in Summit Holdings and is the sole general partner of Summit Holdings. Accordingly, the Company operates and controls all of the business and affairs of Summit Holdings and, through Summit Holdings and its operating entity subsidiaries, conducts our business.

Pursuant to the limited partnership agreement of Summit Holdings, the Company has the right to determine when distributions will be made to holders of LP Units and the amount of any such distributions. If a distribution is authorized, such distribution will be made to the holders of LP Units pro rata in accordance with the percentages of their respective limited partnership interests. The holders of LP Units, including the Company, incur U.S. federal, state and local income taxes on their share of any taxable income of Summit Holdings. The limited partnership agreement of Summit Holdings provides for tax distributions to the holders of the LP Units in an amount generally calculated to provide each holder of LP Units with sufficient cash to cover its tax liability in respect of the LP Units. These tax distributions are generally only paid to the extent that other distributions made by Summit Holdings were otherwise insufficient to cover the estimated tax liabilities of all holders of LP Units. In general, these tax distributions are computed based on our estimate of the net taxable income allocated to the Company multiplied by an assumed tax rate equal to the highest effective marginal combined U.S. federal, state and local income tax rate applicable to a corporate resident in New York, New York. In the year ended December 28, 2019, Summit LLC paid distributions to Summit Holdings totaling $0.1 million, all of which was distributed to Summit Holdings' partners, other than the Company.

The limited partnership agreement of Summit Holdings also provides that substantially all expenses incurred by or attributable to the Company, but excluding obligations incurred under the tax receivable agreement by the Company, income tax expenses of the Company and payments on indebtedness incurred by the Company, will be borne by Summit Holdings.

The Company as the general partner may (i) at any time, require all holders of LP Units, other than holders who are current employees or service providers, to exchange their units for shares of our common stock or (ii) with the consent of partners in Summit Holdings whose vested interests exceed 662/3% of the aggregate vested interests in Summit Holdings, require all holders of interests in Summit Holdings to transfer their interests, provided that the prior written consent of each holder that is an affiliate of Blackstone affected by any such proposed transfer will be required. These provisions are designed to ensure that the general partner can, in the context of a sale of the Company, sell Summit Holdings as a wholly-owned entity subject to the approval of the holders thereof.

Indemnification Agreements

We have entered into indemnification agreements with our directors and executive officers. These agreements require us to indemnify these individuals to the fullest extent permitted by Delaware law against liabilities that may arise by reason of their service to us, and to advance expenses incurred as a result of any proceeding against them as to which they could be indemnified. Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors or executive officers, we have been informed that in the opinion of the SEC such indemnification is against public policy and is therefore unenforceable.

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There is currently no pending material litigation or proceeding involving any of our directors, officers or employees for which indemnification is sought.

Warrant Issuances

In connection with the modification of the capital structure of Summit Holdings at the time of our IPO, we issued warrants to purchase an aggregate of 160,333 shares of Class A Common Stock to limited partners of Summit Holdings who held Class C limited partnership interests of Summit Holdings. Holders of the Class C limited partnership interests include Thomas W. Hill, a limited liability company controlled by Ted A. Gardner, and Michael J. Brady, who received warrants to purchase 29,463, 27,408, and 6,852 shares of Class A Common Stock, respectively. The warrants were issued in substitution for part of the economic benefit of the Class C interests that was not reflected in the conversion of the Class C interests to LP Units. The exercise price of the warrants is equal to the IPO price of $18.00 per share. The warrants became exercisable from and after March 17, 2016 and will expire on March 11, 2025.

Other

Thomas A. Beck, our Executive Vice President and President of our Cement Division, through the Thomas A. Beck Family, LLC (the 'Beck LLC'), is a party to a Contribution and Purchase Agreement, dated December 18, 2014 that we entered into with the former holders of Class B Units of Continental Cement Company, L.L.C. (the 'Former CCC Minority Holders') (the 'Contribution and Purchase Agreement'). In connection with the Contribution and Purchase Agreement, on March 17, 2015, Summit Holdings issued to the Former CCC Minority Holders $15.0 million in aggregate principal amount of non-interest bearing notes payable over six years. The pro rata share of the $15.0 million in notes that is due to the Beck LLC is $208,344, payable in six equal annual installments of $34,724 on each anniversary of March 17, 2015.

Statement of Policy Regarding Transactions with Related Persons

We have adopted a written statement of policy regarding transactions with related persons, which we refer to as our 'related person policy.' Our related person policy requires that a 'related person' (as defined in paragraph (a) of Item 404 of Regulation S-K) must promptly disclose to our Chief Legal Officer any 'related person transaction' (defined as any transaction that is anticipated would be reportable by us under Item 404(a) of Regulation S-K in which we were or are to be a participant and the amount involved exceeds $120,000 and in which any related person had or will have a direct or indirect material interest) and all material facts with respect thereto. The Chief Legal Officer will then promptly communicate that information to our Board. No related person transaction will be executed without the approval or ratification of our Board or a duly authorized committee of our Board. It is our policy that directors interested in a related person transaction will recuse themselves from any vote on a related person transaction in which they have an interest.

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OUR STOCKHOLDERS

HOLDINGS OF MAJOR STOCKHOLDERS

The following table sets forth the beneficial ownership of shares of our Class A Common Stock and LP Units by (1) each person known to us to beneficially own more than 5% of any class of the outstanding voting securities of the Company, (2) each of our directors and NEOs and (3) all of our directors and executive officers as a group as of March 25, 2020.

Class A Common Stock(1) LP Units(1) Combined Voting Power(2)

Stockholder Name

Number Percent Number Percent Number Percent

Vanguard Group Inc.(3)

10,287,018 9.0 % - - 10,287,018 8.8 %

BlackRock, Inc.(4)

8,789,120 7.7 % - - 8,789,120 7.5 %

Janus Henderson Group PLC(5)

8,079,237 7.1 % - - 8,079,237 6.9 %

FMR LLC(6)

7,212,715 6.3 % - - 7,212,715 6.2 %

Thomas W. Hill(7)

871,571 * 544,425 * 1,415,996 1.2 %

Howard L. Lance(8)

269,349 * 135,772 * 405,121 *

Joseph S. Cantie(9)

20,947 * - - 20,947 *

Anne M. Cooney(10)

13,280 * - - 13,280 *

Susan A. Ellerbusch(11)

13,280 * - - 13,280 *

Ted A. Gardner(12)

50,146 * 162,752 * 212,898 *

John R. Murphy(13)

25,857 * 4,274 * 30,131 *

Anne K. Wade(14)

22,738 * - - 22,738 *

Steven H. Wunning(15)

20,924 * - - 20,924 *

Brian J. Harris(16)

152,561 * 332,699 * 485,260 *

Michael J. Brady(17)

464,121 * 283,649 * 747,770 *

Anne Lee Benedict(18)

27,419 * 61,422 * 88,841 *

M. Shane Evans(19)

23,511 * - - 23,511 *

Karl H. Watson(20)

51,236 * - - 51,236 *

All Directors and Executive Officers as a Group (13 persons)(21)

2,010,259 1.7 % 1,551,942 1.3 % 3,562,201 3.0 %
*Less than 1%.

The percentage of beneficial ownership of (1) Class A Common Stock is based upon 114,109,647 shares issued and outstanding and (2) LP Units is based upon 117,162,760 LP Units outstanding (including 114,109,647 LP Units held by the Company), in each case as of March 25, 2020. Percentage of combined voting power is based upon 117,052,510 votes represented by outstanding securities, consisting of (1) 114,109,647 shares of Class A Common Stock issued and outstanding and (2) 2,942,863 LP Units outstanding and eligible to vote, excluding LP Units held by the Company, in each case as of March 25, 2020. The Company is the general partner of Summit Holdings, which indirectly owns 100% of the limited liability interests of Summit Materials, LLC ('Summit LLC'). Except as otherwise noted, (i) the information is as of March 25, 2020, and (ii) the address of each beneficial owner is c/o Summit Materials, Inc., 1550 Wynkoop Street, 3rd floor, Denver, Colorado 80202. Beneficial ownership is determined in accordance with the rules and regulations of the SEC.

(1)Subject to the terms of the Exchange Agreement, LP Units are exchangeable for shares of our Class A Common Stock on a one-for-one basis. See 'Certain Relationships and Related Person Transactions-Exchange Agreement.' Beneficial ownership of LP Units reflected in this table is not reflected as beneficial ownership of shares of our Class A Common Stock for which such units may be exchanged. See 'Executive Compensation-Narrative Disclosure to Summary Compensation Table and Grants of Plan-Based Awards Table-Pre-IPO Long-Term Incentive Awards (Value From Modifications to Eliminate Misalignment Post-IPO)' for a description of the LP Units.

(2)Represents percentage of voting power of the Class A Common Stock and Class B Common Stock of the Company voting together as a single class and gives effect to voting power of the Class B Common Stock, excluding options that are vested or will vest within 60 days as well as outstanding warrants. The Class B Common Stock provides holders who also hold LP Units with a number of votes that is equal to the aggregate number of LP Units held by such holders. As of

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March 25, 2020, holders of the LP Units held all of the issued shares of our Class B Common Stock that were outstanding and the total number of votes that were represented by the Class B Common Stock was 2,942,863. In addition to the voting power of the Class B Common Stock conferred to him and the Hill Trust through their ownership of LP Units, Mr. Hill has sole voting power over 1,988,793 votes represented by the Class B Common Stock through revocable proxies granted to him by certain pre-IPO investors that hold LP Units, including members of management. Mr. Hill has no pecuniary interest in the LP Units held by such other LP Unit holders and disclaims any beneficial ownership in such LP Units.

(3)The number of shares held was obtained from the holder's Schedule 13G/A filing with the SEC on February 12, 2020, which reports ownership as of December 31, 2019. The Schedule 13G/A filing indicates that the holder, The Vanguard Group, Inc. ('Vanguard') has sole power to vote or direct the vote of 132,877 shares of our Common Stock, shared power to vote or direct the vote of 22,592 shares of our Common Stock, sole power to dispose or direct the disposition of 10,146,624 shares of our Common Stock, and shared power to dispose or direct the disposition of 140,394 shares of our Common Stock. The address of Vanguard is 100 Vanguard Blvd., Malvern, PA 19355.

(4)The number of shares held was obtained from the holder's Schedule 13G/A filing with the SEC on February 6, 2020, which reports ownership as of December 31, 2019. The Schedule 13G/A filing indicates that the holder, BlackRock, Inc. ('BlackRock') had sole power to vote or direct the vote of 8,388,834 shares of our Class A Common Stock and sole power to dispose or to direct the disposition of 8,789,120 shares of our Class A Common Stock. The address of BlackRock is 55 East 52nd Street, New York, NY 10055.

(5)The number of shares held was obtained from the holders' Schedule 13G/A filing with the SEC on February 13, 2020, which reports ownership as of December 31, 2019. The Schedule 13G/A filing indicates that the holders, Janus Henderson Group plc ('Janus') and Janus Henderson Contrarian Fund ('Contrarian') had shared power to vote 8,079,237 and 2,118,093 of our Class A Common Stock, respectively, and shared power to dispose or direct the disposition of 8,079,237 and 2,118,093 shares of our Class A Common Stock, respectively. Janus has an indirect 97% ownership stake in Intech Investment Management LLC and a 100% ownership stake in Janus Capital Management LLC ('JCM'), Perkins Investment Management LLC, Geneva Capital Management LLC, Henderson Global Investors Limited and Janus Henderson Investors Australia Institutional Funds Management Limited (each an 'Asset Manager' and collectively as the 'Asset Managers'). Each Asset Manager is an investment adviser registered or authorized in its relevant jurisdiction and each furnishing investment advice to various fund, individual and/or institutional clients (collectively referred to as 'Managed Portfolios'). As a result of its role as investment adviser or sub-adviser to the Managed Portfolios, JCM may be deemed to be the beneficial owner of 8,079,237 shares of the shares outstanding of the Company's Class A Common Stock held by such Managed Portfolios. However, JCM does not have the right to receive any dividends from, or the proceeds from the sale of, the securities held in the Managed Portfolios and disclaims any ownership associated with such rights. Contrarian is an investment company registered under the Investment Company Act of 1940 and is one of the Managed Portfolios to which JCM provides investment advice. The address of Janus is 201 Bishopsgate, EC2M 3AE, United Kingdom. The address of Contrarian is 151 Detroit Street Denver, Colorado 80206.

(6)The number of shares held was obtained from the Schedule 13G filing made by FMR LLC ('FMR') and Abigail P. Johnson with the SEC on February 7, 2020, which reports ownership as of December 31, 2019. The Schedule 13G indicates that FMR has sole power to vote or direct the vote of 2,251,864 shares of our Class A Common Stock and sole power to dispose or direct the disposition of 7,212,715 shares of our Class A Common Stock. The Schedule 13G indicates that Ms. Johnson has sole power to dispose or direct the disposition of 7,212,715 shares of our Class A Common Stock. Members of the Johnson family, including Ms. Johnson, are the predominant owners, directly or through trusts, of Series B voting common shares of FMR LLC, representing 49% of the voting power of FMR LLC. The Johnson family group and all other Series B shareholders have entered into a shareholders' voting agreement under which all Series B voting common shares will be voted in accordance with the majority vote of Series B voting common shares. Accordingly, through their ownership of voting common shares and the execution of the shareholders' voting agreement, members of the Johnson family may be deemed, under the Investment Company Act of 1940, to form a controlling group with respect to FMR LLC. Neither FMR LLC nor Abigail P. Johnson has the sole power to vote or direct the voting of the shares owned directly by the various investment companies registered under the Investment Company Act ('Fidelity Funds') advised by Fidelity Management & Research Company ('FMR Co'), a wholly owned subsidiary of FMR LLC, which power resides with the Fidelity Funds' Boards of Trustees. FMR Co carries out the voting of the shares under written guidelines established by the Fidelity Funds' Boards of Trustees. The address of FMR is 245 Summer Street, Boston, Massachusetts 02210.

(7)Includes (i) 611,351 options, including Leverage Restoration Options (as described in 'Executive Compensation-Narrative Disclosure to Summary Compensation Table and Grants of Plan-Based Awards Table-Pre-IPO Long-Term Incentive Awards (Value From Modifications to Eliminate Misalignment Post-IPO)') issued to Mr. Hill that are vested or will vest within 60 days, (ii) 29,463 warrants issued to Mr. Hill at the time of our IPO, (iii) 230,392 shares of our Class A Common Stock owned by Mr. Hill, (iv) 517,456 LP Units held by Mr. Hill, (v) 365 shares of our Class A Common Stock held by the Hill Trust, a trust for which Mr. Hill's spouse serves as trustee and as to which Mr. Hill could be deemed to have beneficial ownership, and (vi) 26,969 LP Units held by The Hill Trust. See 'Certain Relationships and Related Person Transactions-Warrant Issuances.' Amounts for Mr. Hill do not include 1,988,793 LP Units for which Mr. Hill has sole voting power through revocable proxies granted to him. See footnote (2).

(8)Includes (i) 246,611 options issued to Mr. Lance that are vested or will vest within 60 days, (ii) 135,772 LP Units held by Mr. Lance, and (iii) 22,738 shares of our Class A Common Stock held by Mr. Lance.

(9)Includes 20,947 shares of our Class A Common Stock owned by Mr. Cantie.

(10)Includes 13,280 shares of our Class A Common Stock owned by Ms. Cooney.

(11)Includes 13,280 shares of our Class A Common Stock owned by Ms. Ellerbusch.

(12)Includes (i) 22,738 shares of our Class A Common Stock held by Mr. Gardner, and (ii) 27,408 warrants and (iii) 162,752 LP Units held by Gardner Family Investments, LLC, a limited liability company controlled by Mr. Gardner. Mr. Gardner has sole voting and dispositive power over such warrants and LP Units.

(13)Includes (i) 10,220 options issued to Mr. Murphy that are vested or will vest within 60 days, (ii) 4,274 LP Units held by Mr. Murphy and (iii) 15,637 shares of our Class A Common Stock owned by Mr. Murphy.

(14)Includes 22,738 shares of our Class A Common Stock owned by Ms. Wade.

(15)Includes 20,924 shares of our Class A Common Stock owned by Mr. Wunning.

(16)Includes (i) 47,611 options issued to Mr. Harris that are vested or will vest within 60 days, (ii) 104,950 shares of our Class A Common Stock owned by Mr. Harris, and (iii) 332,699 LP Units held by The Harris Family 2014 Trust fbo Michael J. Harris and The Harris Family 2014 Trust fbo Cameron I.J. Harris, trusts for which Mr. Harris' spouse serves as trustee and as to which Mr. Harris could be deemed to have beneficial ownership.

(17)Includes (i) 430,150 options issued to Mr. Brady that are vested or will vest within 60 days, (ii) 283,649 LP Units held by Mr. Brady, (iii) 27,119 shares of our Class A Common Stock owned by Mr. Brady, and (iv) 6,852 warrants issued to Mr. Brady at the time of our IPO.

(18)Includes (i) 8,962 options issued to Ms. Lee Benedict that are vested or will vest within 60 days, (ii) 61,422 LP Units held by Ms. Lee Benedict, and (iii) 18,457 shares of our Class A Common Stock owned by Ms. Lee Benedict.

(19)Includes (i) 6,324 options issued to Mr. Evans that are vested or will vest within 60 days and (ii) 17,187 shares of our Class A Common Stock owned by Mr. Evans.

(20)Includes 51,236 shares of our Class A Common Stock held by Mr. Watson.

(21)Includes (i) 1,385,935 options that are vested or will vest within 60 days, (ii) 1,551,942 LP Units, (iii) 63,723 warrants issued at the IPO and (iv) 560,601 shares of our Class A Common Stock.

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SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

To our knowledge, based solely on a review of the copies of such reports furnished to us and written representations that no other reports were required, we believe that during the fiscal year ended December 28, 2019, our officers, directors, and greater-than-10% stockholders timely filed all reports required by Section 16(a) of the Exchange Act.

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USERS' GUIDE

Attending the Annual Meeting of Stockholders

WHO CAN ATTEND THE ANNUAL MEETING?

You are entitled to attend the Annual Meeting on Tuesday, May 19, 2020 only if you were a Summit Materials stockholder at the close of business on March 25, 2020, or you hold a valid proxy.

HOW CAN I ATTEND THE ANNUAL MEETING?

We will be hosting the Annual Meeting on the Internet through a virtual web conference. To attend the Annual Meeting via the virtual web conference please go to www.virtualshareholdermeeting.com/SUM2020 and enter the control number found on your proxy card, voting instruction form or notice you received.

WHY IS THE ANNUAL MEETING A VIRTUAL MEETING?

We have decided to hold our Annual Meeting virtually due to COVID-19 (Coronavirus). We are sensitive to the public health and travel concerns of our stockholders and employees and the protocols that federal, state and local governments may impose. We have designed our virtual format to enhance, rather than constrain, stockholder access, participation and communication. For example, the virtual format allows stockholders to communicate with us in advance of, and during, the Annual Meeting so they can ask questions of our Board or management. During the live Q&A session of the Annual Meeting, we may answer questions as they come in and address those asked in advance, to the extent relevant to the business of the Annual Meeting, as time permits. If you encounter any difficulties accessing the virtual web conference of the Annual Meeting, please call 800-586-1548 (U.S.) or 303-562-9288 (International) for assistance. Technical support will be available beginning at 7:30 a.m., Mountain Time, on May 19, 2020 through the conclusion of the Annual Meeting.

In 2021, we plan to to have our annual meeting of stockholders be a hybrid meeting with both a physical and a virtual component.

HOW CAN I ACCESS THE ANNUAL MEETING WEBSITE?

All stockholders can visit the Annual Meeting website at www.proxyvote.com. On our Annual Meeting website, you can vote your proxy, submit questions in advance of the Annual Meeting, access copies of our Proxy Statement and Annual Report and other information about Summit Materials, and elect to view future proxy statements and annual reports online instead of receiving paper copies in the mail.


IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS FOR THE SUMMIT MATERIALS, INC.

ANNUAL MEETING OF STOCKHOLDERS TO BE HELD ON TUESDAY, MAY 19, 2020


THIS NOTICE, OUR PROXY STATEMENT, AND OUR COMBINED ANNUAL REPORT AND ANNUAL REPORT ON
FORM 10-K FOR THE YEAR ENDED DECEMBER 28, 2019 ARE AVAILABLE AT WWW.PROXYVOTE.COM.

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Who Can Vote and How

WHO IS ENTITLED TO VOTE?

You are entitled to vote at the Annual Meeting on Tuesday, May 19, 2020 only if you were a Summit Materials stockholder of record of our Class A Common Stock and Class B Common Stock (each such designation having par value $0.01 per share) at the close of business on March 25, 2020.

On March 25, 2020, we had 114,109,647 shares of Class A Common Stock outstanding and entitled to vote and 99 shares of Class B Common Stock outstanding and entitled to vote. Holders of shares of our Class A Common Stock and Class B Common Stock vote together as a single class on all matters on which stockholders are entitled to vote generally (except as may be required by law).

Each share of Class A Common Stock is entitled to one vote for each director nominee and one vote for each other item to be voted on at the Annual Meeting. All of the shares of our outstanding Class B Common Stock are currently held by our pre-IPO investors, including certain members of management or their family trusts that directly hold LP Units. A holder of Class B Common Stock is entitled, without regard to the number of shares of Class B Common Stock held by such holder, to a number of votes that is equal to the aggregate number of LP Units held by such holder. As of the record date, the total number of LP Units to which the voting power of the Class B Common Stock relates was 2,942,863.

A majority of the voting power of Class A Common Stock and Class B Common Stock entitled to vote, present in person or represented by proxy, constitutes a quorum for the transaction of business at the Annual Meeting. Abstentions and broker non-votes will be included in determining the presence of a quorum at the Annual Meeting.

HOW DO I VOTE?

We encourage you to vote your shares in advance of the Annual Meeting, even if you plan on attending the Annual Meeting. If you have already voted prior to the Annual Meeting, you may nevertheless change or revoke your vote at the Annual Meeting.

Vote your shares as follows. In all cases, have your Notice of Internet Availability of Proxy Materials, proxy card or voting instruction form in hand and follow the instructions.

Vote by Internet. Visit www.proxyvote.com 24/7 to vote by internet using your computer.

Vote by Telephone. Stockholders of record can call toll-free 800-690-6903 24/7 to vote. For beneficial stockholders, please see the voting instruction form 24/7 to vote.

Vote by Mail. If you elected to receive a hard copy of your proxy materials, fill out the enclosed proxy card, date and sign it, and return it in the enclosed postage paid envelope.

Vote During the Annual Meeting via the Internet. You may attend the Annual Meeting via the Internet and vote during the meeting. Go to www.virtualshareholdermeeting.com/SUM2020, enter the control number found on your proxy card, voting instruction form or notice you received, and follow the instructions available on the meeting website during the meeting.

We encourage you to register to receive all future stockholder communications electronically, instead of in print. This means that, after you register, access to the annual report, proxy statement, and other correspondence will be delivered to you via e-mail.

CAN I CHANGE MY VOTE?

If you own common stock of record, you may change your vote at any time before the polls close at the Annual Meeting. You can do this by:

• Voting again by Internet or telephone prior to 11:59 p.m. Eastern Time on May 18, 2020;

• Signing another proxy card with a later date and returning it prior to the Annual Meeting; or

• Voting again during the Annual Meeting.

A stockholder owning common stock in street name may revoke or change voting instructions by contacting the bank, brokerage firm or other nominee holding the shares.

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WHO COUNTS THE VOTES?

We have hired Broadridge Financial Solutions, Inc. to count the votes represented by proxies and cast by ballot, and Broadridge Financial Solutions, Inc. has been appointed to act as Inspector of Election.

WHEN WILL THE VOTING RESULTS BE ANNOUNCED?

We will announce the preliminary voting results during the Annual Meeting. We will report the final results on our website and in a Current Report on Form 8-K filed with the SEC within four days following the meeting.

WILL MY VOTE BE CONFIDENTIAL?

All stockholder proxies, ballots and tabulations that identify stockholders will be maintained in confidence. No such document will be available for examination, and the identity and vote of any stockholder will not be disclosed, except as necessary to meet legal requirements and to allow the inspectors of election to certify the results of the vote.

Business Taking Place at the Annual Meeting

WHICH PROPOSALS ARE BEING VOTED ON AT THE ANNUAL MEETING?

• The election of each of the two nominees to the Board named herein;

• The ratification of the appointment of our independent registered public accounting firm; and

• The approval, on a nonbinding advisory basis, of the compensation of our NEOs as disclosed in this Proxy Statement.

WHICH PROPOSALS ARE 'ROUTINE' AND WHICH ARE 'NON-ROUTINE'?

The ratification of KPMG LLP as our independent registered public accounting firm for our fiscal year ending January 2, 2021 is the only routine matter to be presented at the Annual Meeting. The other two matters-the election of two Board of Director nominees and the approval of the compensation of our named executive officers-are non-routine and brokers will not be allowed to vote on these proposals without specific voting instructions from beneficial owners. We do not expect any additional matters will be brought before the Annual Meeting. However, if other matters are properly presented, the persons named as proxies in the proxy card or their substitutes will vote in their discretion.

HOW MANY VOTES ARE NEEDED TO APPROVE EACH PROPOSAL?

With respect to the election of directors, a nominee for director shall be elected to the Board by a plurality of the votes cast in respect of the shares of common stock present in person or represented by proxy at the Annual Meeting and entitled to vote on the election of directors. A plurality vote requirement means that the director nominees with the greatest number of votes cast 'FOR', even if it is less than a majority, will be elected. You may vote 'FOR' or 'WITHHOLD' with respect to each nominee. A withhold vote in the election of directors will have the same effect as an abstention. Neither a withhold vote nor a broker non-vote will affect the outcome of the election of directors.

The affirmative vote of a majority of the voting power of common stock present in person or represented by proxy and entitled to vote on the matter is required to ratify the appointment of KPMG as our independent registered public accounting firm and to approve, on a nonbinding advisory basis, the compensation of our NEOs, as disclosed in this Proxy Statement. You may vote 'FOR,' 'AGAINST,' or 'ABSTAIN' with respect to these matters. For these matters, abstentions are not counted as affirmative votes but are counted as present at the Annual Meeting and entitled to vote and will have the effect of a vote 'against' the matter. Broker non-votes, if any, will have no effect on the outcome of these matters.

Proxies

WHO IS SOLICITING MY PROXY?

The Board of Summit Materials is soliciting your proxy to vote at the 2020 Annual Meeting of Stockholders.

HOW CAN I REVOKE MY PROXY?

You can revoke your proxy by sending written notice of revocation to our Chief Legal Officer & Secretary at Summit Materials, Inc., 1550 Wynkoop Street, 3rd Floor, Denver, Colorado 80202, by May 18, 2020.

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WHAT IS THE COST OF THIS PROXY SOLICITATION?

The Company will pay the costs of preparing, printing, assembling, and mailing the proxy materials used in the solicitation of proxies. Solicitation may be made by our directors, officers, and employees by mail, email, telephone, or in person. Those individuals will receive no additional compensation for solicitation activities. We have hired Innisfree M&A Incorporated to assist in the solicitation of proxies, who will receive a fee of $20,000, plus reasonable out of pocket costs and expenses, for its services. Broadridge will distribute proxy materials to banks, brokers, and other nominees for forwarding to beneficial owners and will request brokerage houses and other custodians, nominees, and fiduciaries to forward soliciting material to the beneficial owners of the common stock held on the record date by such persons. We will reimburse brokerage houses and other custodians, nominees and fiduciaries for their expenses in forwarding solicitation materials.

Getting Our Proxy Statement and Annual Report

HOW CAN I ACCESS PROXY MATERIALS ONLINE?

This Proxy Statement, the accompanying proxy card, and our 2019 Annual Report are being made available to stockholders online at www.proxyvote.com.

Instead of mailing printed copies of these materials, we will send some of our stockholders a Notice of Internet Availability of Proxy Materials ('Notice'). If you received a Notice and would prefer to receive a paper copy of our proxy materials, follow the instructions included in the Notice to update your preferences. If you elect to receive our future proxy materials electronically, you will receive access to those materials via e-mail unless and until you elect otherwise.

WHY DID MY HOUSEHOLD RECEIVE A SINGLE SET OF PROXY MATERIALS?

SEC rules permit us to deliver a single copy of our 2019 Annual Report and Proxy Statement to any household at which two or more stockholders reside if we believe the stockholders are members of the same family. This practice benefits both you and Summit Materials, as it eliminates duplicate mailings and reduces our printing and mailing costs. Each stockholder will continue to receive a separate proxy card or voting instruction card.

Your household may have received a single set of proxy materials this year. If you prefer to receive your own copy now or in future years, please request a duplicate set by phone at 1-866-540-7095, online at www.proxyvote.com, or by writing to Summit Materials, c/o Broadridge, 51 Mercedes Way, Edgewood, NY 11717.

If you hold your stock in street name, you may receive some duplicate mailings. Certain brokers will eliminate duplicate account mailings on request. You may need to contact your broker directly if you want to discontinue duplicate mailings to your household. You can also register to receive all future stockholder communications electronically, instead of in print. This means that links to the annual report, proxy statement, and other correspondence will be delivered to you via e-mail. Holders in street name can register for electronic delivery directly with their bank, brokerage firm, or other nominee. Electronic delivery of stockholder communications helps save the Company money by reducing printing and postage costs.

Future Shareholder Proposals and Nominations

RULE 14A-8 SHAREHOLDER PROPOSAL

Under SEC rules, if you want us to include a proposal in our proxy statement for the 2021 Annual Meeting of Stockholders, you must submit it in writing to our Chief Legal Officer & Secretary at Summit Materials, Inc., 1550 Wynkoop Street, 3rd Floor, Denver, Colorado 80202, by December 4, 2020. Any such proposal should comply with the requirements of Rule 14a-8 promulgated under the Securities Exchange Act. The submission of a shareholder proposal does not guarantee that it will be included in our proxy statement.

PROXY ACCESS NOMINATIONS AND OTHER PROPOSALS/NOMINATIONS

Under our Bylaws, a stockholder wishing to bring director nominations or other business before an annual meeting is required to provide advance written notice to the Chief Legal Officer & Secretary of Summit Materials regarding such nominations or other business and provide the information and satisfy the other requirements set forth in the Bylaws. To be timely, a stockholder who intends to present nominations or a proposal at the 2021 Annual Meeting other than pursuant to Rule 14a-8 must provide the information set forth in the Bylaws no earlier than January 19, 2021 and no later than February 18, 2021. However, if we hold the 2021 Annual Meeting more than 30 days before, or more than 70 days after, the anniversary of the 2020 Annual Meeting date, then the information must be received no earlier than the 120th day prior to the 2021 Annual Meeting date, and not later than the close of business on the later of the 90th day prior to the 2021 Annual Meeting date or the tenth day after public

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announcement of the 2021 Annual Meeting date. These advance notice provisions do not apply if the stockholder only seeks to include such matters in the proxy statement pursuant to Rule 14a-8.

If a stockholder fails to meet these deadlines and fails to satisfy the requirements of Rule 14a-4 under the Securities Exchange Act, we may exercise discretionary voting authority under proxies we solicit to vote on any such proposal as we determine appropriate. We also reserve the right to reject, rule out of order, or take other appropriate action with respect to any nomination or proposal that does not comply with these and other applicable requirements.

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ANNEX A

RECONCILIATION OF
NON-GAAP MEASURES TO GAAP

The table below reconciles our net income to Adjusted EBITDA and Net Leverage for the year ended December 28, 2019 and December 29, 2018.

Year ended
December 28, 2019 ($) December 29, 2018 ($)

Reconciliation of Net Income to Adjusted EBITDA

(dollars in millions)

Net income

61 36

Interest expense

117 117

Income tax expense

17 60

Depreciation, depletion and amortization

215 203

EBITDA

410 416

Accretion

2 2

Loss on debt financings

15 -

Tax receivable agreement expense (benefit)

16 (23)

Gain on sale of business

- (12)

Transaction costs

2 4

Non-cash compensation

20 25

Other(1)

(4) (6)

Adjusted EBITDA

461 406

EBITDA for certain completed acquisitions(2)

- 2

Further Adjusted EBITDA(3)

461 408

Net Debt

1,667 1,828

Net Leverage (4)

3.6x 4.5x
(1)In the year ended December 28, 2019, we negotiated a $2.0 million reduction in the amount of a contingent liability from one of our acquisitions. In the year ended December 29, 2018, we negotiated a $6.9 million reduction in the amount of a contingent liability from one of our acquisitions. As we had passed the period to revise the opening balance sheet for this acquisition, the adjustment was recorded in the respective period as other income.

(2)EBITDA for certain completed acquisitions, net of dispositions, is pro forma for all acquisitions completed as of the date listed.

(3)Further Adjusted EBITDA is calculated using trailing four quarter financial data to test compliance with covenants under our senior secured credit facilities.

(4)Net Leverage is defined as Net Debt divided by Further Adjusted EBITDA.

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The table below reconciles our long-term debt to net debt for the year ended December 28, 2019 and December 29, 2018.

Year ended
December 28, 2019 ($) December 29, 2018 ($)

Reconciliation of Long-Term Debt to Net Debt

(dollars in millions)

Long-term debt, including current portion

1,874 1,831

Acquisition related liabilities

48 77

Finance leases and other

56 49

Less: Cash and cash equivalents

(311) (129)

Net debt

1,667 1,828

The table below reconciles our net income to Adjusted EBITDA for the West Segment for the year ended December 28, 2019 and December 29, 2018.

Year ended
December 28, 2019 ($) December 29, 2018 ($)

Reconciliation of Net Income to Adjusted EBITDA for the West Segment

(dollars in thousands)

Net income

30,735 11,738

Interest (income) expense

(171) 950

Income tax expense (benefit)

440 (81)

Depreciation, depletion and amortization

22,986 23,627

EBITDA

53,990 36,234

Accretion

114 138

Tax receivable agreement expense

- -

Transaction costs

84 1

Non-cash compensation

- -

Other

(278) 1,310

Adjusted EBITDA

53,910 37,683

The table below reconciles our net cash provided by operating activities to free cash flow for the year ended December 28, 2019 and December 29, 2018.

Year ended
December 28, 2019 ($) December 29, 2018 ($)

Reconciliation of Net Cash Provided by Operating Activities to Free Cash Flow

(dollars in thousands)

Net income

61,123 36,330

Non-cash items

249,698 263,565

Net income adjusted for non-cash items

310,821 299,895

Change in working capital accounts

26,363 (90,527)

Net cash provided by operating activities

337,184 209,368

Capital expenditures, net of asset sale

(156,322) (199,050)

Free cash flow

180,862 10,318

58 | SUMMIT MATERIALS 2020 NOTICE OF ANNUAL MEETING AND PROXY STATEMENT

VOTE BY INTERNET Before The Meeting - Go to www.proxyvote.com Use the Internet to transmit your voting instructions and for electronic delivery of information up until 11:59 p.m. Eastern Time the day before the cut-off date or meeting date. Have your proxy card in hand when you access the web site and follow the instructions to obtain your records and to create an electronic voting instruction form. BROADRIDGE CORPORATE ISSUER SOLUTIONS C/O SUMMIT MATERIALS, INC. P.O. BOX 1342 BRENTWOOD, NY 11717 During The Meeting - Go to www.virtualshareholdermeeting.com/SUM2020 You may attend the meeting via the Internet and vote during the meeting. Have the information that is printed in the box marked by the arrow available and follow the instructions. VOTE BY PHONE - 1-800-690-6903 Use any touch-tone telephone to transmit your voting instructions up until 11:59 p.m. Eastern Time the day before the cut-off date or meeting date. Have your proxy card in hand when you call and then follow the instructions. VOTE BY MAIL Mark, sign and date your proxy card and return it in the postage-paid envelope we have provided or return it to Vote Processing, c/o Broadridge, 51 Mercedes Way, Edgewood, NY 11717. TO VOTE, MARK BLOCKS BELOW IN BLUE OR BLACK INK AS FOLLOWS: E99656-P34641 KEEP THIS PORTION FOR YOUR RECORDS DETACH AND RETURN THIS PORTION ONLY THIS PROXY CARD IS VALID ONLY WHEN SIGNED AND DATED. SUMMIT MATERIALS, INC. The Board of Directors recommends you vote FOR the following: For Withhold For All AllAllExcept To withhold authority to vote for any individual nominee(s), mark 'For All Except' and write the number(s) of the nominee(s) on the line below. ! ! ! 1. Election of Directors Nominees: 01) John R. Murphy 02) Steven H. Wunning The Board of Directors recommends you vote FOR proposals 2 and 3. For Against Abstain ! ! ! ! ! ! 2. Nonbinding advisory vote on the compensation of our named executive officers for 2019. 3. Ratification of the appointment of KPMG LLP as our independent auditors for our fiscal year ending January 2, 2021. NOTE: Such other business as may properly come before the meeting or any adjournment or postponement thereof. Please sign exactly as your name(s) appear(s) hereon. When signing as attorney, executor, administrator, or other fiduciary, please give full title as such. Joint owners should each sign personally. All holders must sign. If a corporation or partnership, please sign in full corporate or partnership name by authorized officer. Signature [PLEASE SIGN WITHIN BOX] Date Signature (Joint Owners) Date

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting: The Notice and Proxy Statement and Annual Report are available at www.proxyvote.com. E99657-P34641 SUMMIT MATERIALS, INC. Annual Meeting of Stockholders May 19, 2020, 8:00 A.M., Mountain Time This proxy is solicited by the Board of Directors The undersigned hereby appoint(s) Thomas W. Hill, Anne Lee Benedict, and Brian J. Harris, and each of them, each with full power of substitution, as proxies, and hereby authorize(s) them to represent and to vote, as designated on the reverse side of this ballot, all of the shares of Class A Common Stock and/or Class B Common Stock of Summit Materials, Inc. (the 'Company') that the undersigned is/are entitled to vote at the Annual Meeting of Stockholders to be held at 8:00 A.M., Mountain Time, on the Internet through a virtual web conference at www.virtualshareholdermeeting.com/SUM2020, and at any adjournment or postponement thereof. This proxy, when properly executed, will be voted in the manner directed herein. If no such direction is given, this proxy will be voted 'FOR' all portions of items (1), (2), and (3); and in the proxies' discretion on any other matters coming before the meeting or any adjournment or postponement thereof. Continued and to be signed on reverse side


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