Amendment to Registration Statement - Specified Transactions (Form S-3/A)

As filed with the Securities and Exchange Commission on December 8, 2021

Registration No. 333-260783

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

AMENDMENT NO. 1 TO

FORM S-3
REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

MultiPlan Corporation
(Exact Name of Registrant as Specified in Its Charter)

Delaware	83-3536151
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification Number)

115 Fifth Avenue
New York, New York 10003
(212) 780-2000

(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant's Principal Executive Offices)

Mark Tabak
Chief Executive Officer
MultiPlan Corporation
115 Fifth Avenue
New York, New York 10003
(212) 780-2000

(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent For Service)

Copies to:

William B. Brentani Simpson Thacher & Bartlett LLP 2475 Hanover Street Palo Alto, California 94304 (650) 251-5000	Jeffrey Doctoroff Senior Vice President, General Counsel and Secretary MultiPlan Corporation 115 Fifth Avenue New York, New York 10003 (212) 780-2000

Approximate date of commencement of proposed sale to the public: From time to time after this Registration Statement becomes effective.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, please check the following box. ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ☐

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 under the Securities Exchange Act of 1934:

Large accelerated filer	o	Accelerated filer	o
Non-accelerated filer	x	Smaller reporting company	o
Emerging growth company	o

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment that specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

The information in this prospectus is not complete and may be changed. The Selling Securityholders may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED DECEMBER 8, 2021

Preliminary Prospectus

130,000,000 Shares of Class A Common Stock

This prospectus relates to the offer and resale from time to time by the selling securityholders named in this prospectus or in supplements to this prospectus (the "Selling Securityholders"), or their permitted transferees, of up to 130,000,000 shares of our Class A common stock, par value $0.0001 per share ("Class A common stock"). All of the shares of Class A common stock being offered for resale by the Selling Securityholders pursuant to this prospectus are shares of Class A common stock issuable to the Selling Securityholders upon conversion of the 6.00% / 7.00% Convertible Senior PIK Toggle Notes due 2027 (the "Notes") issued by us in a private placement completed on October 8, 2020.

The conversion rate, and therefore the number of shares of Class A common stock issuable to Selling Securityholders upon conversion of the Notes, is subject to adjustment in certain circumstances. Accordingly, the number of shares of Class A common stock issuable with respect to the Notes may increase or decrease.

Our shares of Class A common stock are currently listed on New York Stock Exchange under the symbol "MPLN."

Our registration of the securities covered by this prospectus does not mean that the Selling Securityholders will offer or sell any of the securities. The Selling Securityholders may offer and sell the securities covered by this prospectus in a number of different ways and at varying prices. We provide more information about how the Selling Securityholders may sell the shares in the section entitled "Plan of Distribution." We will not receive any proceeds from the sale of shares of Class A common stock by the Selling Securityholders pursuant to this prospectus. However, we will pay the expenses, other than underwriting discounts and commissions and expenses incurred by the Selling Securityholders for brokerage, accounting, tax or legal services or any other expenses incurred by the Selling Securityholders in disposing of the securities, associated with the sale of securities pursuant to this prospectus.

You should read this prospectus and any prospectus supplement or amendment carefully before you invest in our securities. Our Class A common stock is listed on The New York Stock Exchange under the symbol "MPLN." On December 8, 2021, the last reported sale price of our Class A common stock on The New York Stock Exchange was $4.44 per share.

Investing in our securities involves a high degree of risk. See the section titled "Risk Factors" beginning on page 10.

Neither the Securities and Exchange Commission nor any other state securities commission has approved or disapproved of these securities or passed on the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

, 2021

TABLE OF CONTENTS

Page

About this Prospectus	2
Frequently Used Terms	3
Cautionary Note Regarding Forward-Looking Statements	6
Our Company	8
Risk Factors	10
Use of Proceeds	11
Selling Securityholders	12
Description of Securities	14
Certain United States Federal Income Tax Consequences to Non-U.S. Holders	23
Plan of Distribution	26
Legal Matters	30
Experts	30
Where You Can Find More Information	31
Incorporation by Reference	32

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the SEC using a "shelf" registration process. Under this shelf registration process, the Selling Securityholders may from time to time offer and sell shares of our Class A common stock described in this prospectus in one or more offerings. We may use the shelf registration statement to issue up to an aggregate of 130,000,000 shares of Class A common stock issuable upon conversion of the Notes. The Selling Securityholders may use the shelf registration statement to offer and sell up to an aggregate of 130,000,000 shares of Class A common stock issuable upon conversion of the Notes through any means described in the section entitled "Plan of Distribution." More specific terms of any securities that the Selling Securityholders offer and sell may be provided in a prospectus supplement that describes, among other things, the specific amounts and prices of the Class A common stock being offered and the terms of the offering.

A prospectus supplement may also add, update or change information included in this prospectus. Any statement contained in this prospectus will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in such prospectus supplement modifies or supersedes such statement. Any statement so modified will be deemed to constitute a part of this prospectus only as so modified, and any statement so superseded will be deemed not to constitute a part of this prospectus. You should rely only on the information contained in this prospectus, any applicable prospectus supplement and any related free writing prospectus together with the additional information to which we refer you to in the sections of this prospectus entitled "Where You Can Find More Information" and "Incorporation by Reference."

Neither we nor the Selling Securityholders have authorized anyone to provide any information or to make any representations other than those contained in this prospectus, any accompanying prospectus supplement or any free writing prospectus we have prepared. We and the Selling Securityholders take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. This prospectus is an offer to sell only the securities offered hereby and only under circumstances and in jurisdictions where it is lawful to do so. No dealer, salesperson or other person is authorized to give any information or to represent anything not contained in this prospectus, any applicable prospectus supplement or any related free writing prospectus. This prospectus is not an offer to sell securities, and it is not soliciting an offer to buy securities, in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus or any prospectus supplement is accurate only as of the date on the front of those documents only, regardless of the time of delivery of this prospectus or any applicable prospectus supplement, or any sale of a security. Our business, financial condition, results of operations and prospects may have changed since those dates.

This prospectus contains or incorporates by reference summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed, will be filed or will be incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described below under "Where You Can Find More Information" and "Incorporation by Reference."

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FREQUENTLY USED TERMS

Unless otherwise stated in this prospectus or the context otherwise requires, references to:

"2020 Omnibus Incentive Plan" are to our 2020 Omnibus Incentive Plan, as it may be amended and/or restated from time to time;

"5.750% Notes" are to the $1,300,000,000 in aggregate principal amount of 5.750% Senior Notes due 2028 issued by MPH;

"7.125% Notes" are to the 7.125% Senior Notes due 2024 issued by MPH. All of the outstanding 7.125% Notes were redeemed on October 29, 2020;

"Board" are to the board of directors of the Company;

"Churchill" are to Churchill Capital Corp III, a Delaware corporation, which changed its name to MultiPlan Corporation following the consummation of the Transactions;

"Churchill IPO" are to the initial public offering by Churchill which closed on February 19, 2020;

"Churchill's Class A common stock" are, prior to consummation of the Transactions, to Churchill's Class A common stock, par value $0.0001 per share and, following consummation of the Transactions, to our Class A common stock, par value $0.0001 per share;

"Churchill's Class B common stock" are to Churchill's Class B common stock, par value $0.0001 per share;

"Class A common stock" are to MultiPlan's Class A common stock, par value $0.0001 per share;

"Closing" are to the consummation of the Mergers;

"Closing Date" are to October 8, 2020, the date on which the Transactions were consummated;

"Common PIPE Investment" are to the private placement pursuant to which Churchill entered into subscription agreements with certain investors whereby such investors subscribed for (a) 130,000,000 shares of Churchill's Class A common stock at a purchase price of $10.00 per share for an aggregate commitment of $1,300,000,000 and (b) warrants to purchase 6,500,000 shares of Churchill's Class A Common Stock (for each share of Churchill's Class A common stock subscribed, the investor received 1/20th of a warrant to purchase one share of Churchill's Class A common stock, with each whole warrant having a strike price of $12.50 per share and a maturity date of October 8, 2025). The Common PIPE Investment was subject to an original issue discount (which was paid in additional shares of Churchill's Class A common stock) of 1% for subscriptions of $250,000,000 or less and 2.5% for subscriptions of more than $250,000,000, which resulted in an additional 2,050,000 shares of Churchill's Class A common stock being issued. The Common PIPE Investment was consummated on the Closing Date;

"common stock" are, prior to the consummation of the Transactions, to Churchill's Class A common stock and Churchill's Class B common stock and, following consummation of the Transactions, to the Class A common stock;

"Company" are, prior to the consummation of the Transactions, to Churchill and, following consummation of the Transactions, to MultiPlan Corporation;

"Convertible PIPE Investment" are to the private placement pursuant to which the Company entered into subscription agreements with certain investors whereby such Convertible PIPE Investors agreed to buy $1,300,000,000 in aggregate principal amount of the Notes. The Convertible PIPE Investment was consummated on the Closing Date;

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"Convertible PIPE Investors" are to the investors participating in the Convertible PIPE Investment;

"Convertible Subscription Agreement" are to the subscription agreements, dated as of July 12, 2020, entered into in connection with the Convertible PIPE Investment;

"certificate of incorporation" are to the Company's second amended and restated certificate of incorporation in effect as of the date of this prospectus;

"DGCL" are to the Delaware General Corporation Law, as amended;

"Exchange Act" are to the Securities Exchange Act of 1934, as amended;

"First Merger Sub" are to Music Merger Sub I, Inc. a Delaware corporation and direct, wholly owned subsidiary of the Company;

"H&F" are to Hellman & Friedman Capital Partners VIII, L.P.;

"Holdings" are to Polaris Investment Holdings, L.P.;

"Insiders" are to Michael Klein, Jay Taragin, Jeremy Paul Abson, Glenn R. August, Mark Klein, Malcolm S. McDermid, and Karen G. Mills;

"Investor Rights Agreement" are to the Investor Rights Agreement, dated as of July 12, 2020, by and among the Company, the Sponsor, Holdings, H&F, the PIF and certain other parties thereto;

"M. Klein and Company" are to M. Klein and Company, LLC, a Delaware limited liability company, and its affiliates;

"Merger Agreement" are to that certain Agreement and Plan of Merger, dated as of July 12, 2020, by and among Churchill, MultiPlan Parent, Holdings, First Merger Sub and Second Merger Sub, as the same has been or may be amended, modified, supplemented or waived from time to time;

"Mergers" are to, together, (a) the merger of First Merger Sub with and into MultiPlan Parent with MultiPlan Parent being the surviving company in the merger (the "First Merger") and (b) immediately following and as part of the same transaction as the First Merger, the merger of MultiPlan Parent with and into Second Merger Sub, with Second Merger Sub surviving the merger as a wholly owned subsidiary of Churchill (the "Second Merger");

"MPH" are to MPH Acquisition Holdings LLC;

"MultiPlan" are, prior to consummation of the Transactions, to MultiPlan Parent and its consolidated subsidiaries and, following consummation of the Transactions, to MultiPlan Corporation and its consolidated subsidiaries;

"MultiPlan Parent" are to Polaris Parent Corp., a Delaware corporation;

"non-employee director" are to each member of our Board that is not an employee of the Company or any parent or subsidiary of the Company;

"Notes" are to the $1.3 billion aggregate principal amount of 6.00% / 7.00% Convertible Senior PIK Toggle Notes due 2027 issued by the Company in connection with the Convertible PIPE Investment;

"PIF" are to The Public Investment Fund of The Kingdom of Saudi Arabia;

"PIPE Investment" are to, collectively, the Common PIPE Investment and the Convertible PIPE Investment;

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"PIPE Warrants" are to the warrants to purchase Churchill's Class A common stock issued in connection with the Common PIPE Investment, on terms identical to the terms of the Private Placement Warrants;

"Private Placement Warrants" are to the warrants issued to the Sponsor in a private placement

simultaneously with the closing of the Churchill IPO;

"Public Warrants" are to the Company's warrants sold as part of the units in the Churchill IPO (whether they were purchased in the Churchill IPO or thereafter in the open market);

"Refinancing" are to (a) the consummation of the 5.750% Notes offering by MPH and the increase of the revolving credit facility under the senior secured credit facilities from $100.0 million to $450.0 million and (b) the repayment of all outstanding 7.125% Notes and $369.0 million of indebtedness under MPH's term loan facility with the net proceeds of the 5.750% Notes offering, together with cash on hand, which occurred on October 29, 2020;

"revolving credit facility" are to MPH's $450.0 million senior secured revolving credit facility maturing on June 7, 2023 entered into in connection with the Refinancing;

"SEC" are to the United States Securities and Exchange Commission;

"Second Merger Sub" are to Music Merger Sub II, LLC a Delaware limited liability company and direct, wholly owned subsidiary of the Company;

"Securities Act" are to the Securities Act of 1933, as amended;

"senior secured credit facilities" are to MPH's senior secured credit facilities which consist of (a) a $2,341.0 million term loan facility maturing on June 7, 2023 and (b) a $450.0 million revolving credit facility maturing on June 7, 2023, in each case entered into in connection with the Refinancing;

"Sponsor" are to Churchill Sponsor III, LLC, a Delaware limited liability company and an affiliate of M. Klein and Company in which certain of Churchill's directors and officers hold membership interests;

"Sponsor Agreement" are to the Amended and Restated Sponsor Agreement, dated as of July 12, 2020, by and among the Company, the Sponsor and the Insiders;

"Sponsor Note" are to the unsecured promissory note issued by the Company to the Sponsor in an aggregate principal amount of $1,500,000. The Sponsor converted the unpaid balance of the Sponsor Note into Working Capital Warrants in connection with the Closing;

"term loan facility" are to the MPH $2,341.0 million senior secured term loan facility maturing on June 7, 2023 entered into in connection with the Refinancing;

"Transactions" are to the Mergers, together with the other transactions contemplated by the Merger Agreement and the related agreements;

"warrants" are to the Public Warrants, the Private Placement Warrants, the PIPE Warrants and the Working Capital Warrants;

"we," "our" or "us" are to MultiPlan and its consolidated subsidiaries; and

"Working Capital Warrants" are to the warrants to purchase Churchill's Class A common stock pursuant to the terms of the Sponsor Note, on terms identical to the terms of the Private Placement Warrants.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, any accompanying prospectus supplement and the documents incorporated by reference herein and therein may include statements that express our and our subsidiaries' opinions, expectations, beliefs, plans, objectives, assumptions or projections regarding future events or future results and therefore are, or may be deemed to be, "forward-looking statements." These forward-looking statements can generally be identified by the use of forward-looking terminology, including the terms "believes," "estimates," "anticipates," "expects," "seeks," "projects," "forecasts," "intends," "plans," "may," "will" or "should" or, in each case, their negative or other variations or comparable terminology. These forward-looking statements include all matters that are not historical facts. They may appear in a number of places throughout this prospectus, any accompanying prospectus supplement and the documents incorporated by reference herein and therein and these forward-looking statements reflect management's expectations regarding our future growth, results of operations, operational and financial performance and business prospects and opportunities. Such forward-looking statements are based on available current market material and management's expectations, beliefs and forecasts concerning future events impacting our business. Factors that may impact such forward-looking statements include:

•the impact from the COVID-19 pandemic and its related effects on our projected results of operations, financial performance or other financial metrics;

•loss of our customers, particularly our largest customers;

•decreases in our existing market share or the size of our Preferred Provider Organization ("PPO") networks;

•effects of competition;

•effects of pricing pressure;

•the inability of our customers to pay for our services;

•decreases in discounts from providers;

•the loss of our existing relationships with providers;

•the loss of key members of our management team;

•pressure to limit access to preferred provider networks;

•the ability to achieve the goals of our strategic plans and recognize the anticipated strategic, operational, growth and efficiency benefits when expected;

•our ability to identify, complete and successfully integrate acquisitions;

•changes in our industry;

•interruptions or security breaches of our information technology systems;

•our ability to protect proprietary applications;

•our inability to expand our network infrastructure;

•our ability to remediate any material weakness or maintain effective internal controls over financial reporting;

•changes in our regulatory environment, including healthcare law and regulations;

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•the expansion of privacy and security laws;

•heightened enforcement activity by government agencies;

•our ability to pay interest and principal on our notes and other indebtedness;

•the possibility that we may be adversely affected by other political, economic, business, and/or competitive factors;

•other factors disclosed in this prospectus; and

•other factors beyond our control.

The forward-looking statements contained in this prospectus, any prospectus supplement and the documents incorporated by reference herein and therein are based on our current expectations and beliefs concerning future developments and their potential effects on our business. There can be no assurance that future developments affecting our business will be those that we have anticipated. These forward-looking statements involve a number of risks, uncertainties (some of which are beyond our control) or other assumptions that may cause actual results or performance to be materially different from those expressed or implied by these forward-looking statements. These risks and uncertainties include, but are not limited to, those factors referred to under the heading "Risk Factors." Should one or more of these risks or uncertainties materialize, or should any of the assumptions prove incorrect, actual results may vary in material respects from those projected in these forward-looking statements. Forward looking statements speak only as of the date made. We do not undertake any obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as may be required under applicable securities laws.

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OUR COMPANY

This summary highlights information contained elsewhere or incorporated by reference in this prospectus. This summary does not contain all of the information that you should consider before investing in our Class A common stock. You should read this entire prospectus carefully, including the matters discussed under the sections titled "Risk Factors" and our historical consolidated financial statements and related notes incorporated by reference from our other filings with the SEC before making an investment decision.

MultiPlan is a leading value-added provider of data analytics and technology-enabled end-to-end cost management, payment and revenue integrity solutions to the U.S. healthcare industry. We are also one of the largest independent PPOs in the U.S., with contracted providers in all 50 states and the District of Columbia. We are committed to helping healthcare payors manage the cost of care, improve their competitiveness and inspire positive change. Leveraging sophisticated technology, data analytics and a team rich with industry experience, MultiPlan interprets clients' needs and customizes innovative solutions through the following offerings:

•Analytics-Based Services: data-driven algorithms which detect claims over-charges and recommend or negotiate fair reimbursement;

•Network-Based Services: contracted discounts with healthcare providers, including one of the largest independent preferred provider organizations in the United States, and outsourced network development and/or management services; and

•Payment and Revenue Integrity Services: data, technology, and clinical expertise deployed to identify and remove improper and unnecessary charges before or after claims are paid, or to identify and help restore and preserve underpaid premium dollars.

Our customers include large national insurance companies, Blue Cross and Blue Shield plans, provider-sponsored health plans, third party administrators, bill review companies, Taft-Hartley plans and other entities that pay medical bills related to the commercial healthcare, government, workers' compensation and auto medical markets (collectively, "payors"). We offer these payors a single electronic gateway to a comprehensive set of services in each of the three categories (Analytics-Based Services, Network-Based Services and Payment and Revenue Integrity Services) which are used in combination or individually to reduce the medical cost burden on healthcare payors and patients while fostering efficient payments to the providers. These offerings have enabled us to maintain long-term relationships with a number of our customers, including relationships of over 25 years with some of the nation's largest commercial payors.

Payors generally aim to pay provider claims at a discount to reduce cost, to eliminate any improperly billed charges before payment is made, and to recover any incorrectly paid charges after payment is made. Our Analytics-Based Services discount claims using data-driven negotiation and/or re-pricing methodologies to support payments to providers with whom contractual discounts are not possible and are generally priced based on a percentage of savings achieved. Also included in this category are services that enable lower cost health plans that feature reference-based pricing either in conjunction with or in place of a provider network. These services are generally priced at a bundled per-employee-per-month rate. Our Network-Based Services offer payors a broad network of discounted rates for providers with whom payors do not have a contractual relationship, and are priced based on either a percentage of savings achieved or at a per employee/member per month fee. This service category also includes customized network development and management services for payors seeking to expand their network footprint using outsourced services. These build services are generally priced on a per contract or other project-based price. Our Payment and Revenue Integrity Services use data, technology and clinical expertise to assist payors in identifying improper, unnecessary and excessive charges before or after claims are paid, as well as issues with premiums paid by the Centers for Medicare & Medicaid Services for government health plans caused by discrepancies with enrollment-related data. Payment and Revenue Integrity Services are generally priced based on a percentage of savings achieved.

We believe that our solutions provide a strong value proposition to payors and their insureds, policyholders or health plan members (collectively, "consumers"), as well as to providers. We are deeply integrated in the claims operations processes of our customers with a significant IT and business process burden to displace. Overall, our

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service offerings aim to reduce healthcare costs for payors and consumers in a manner that is orderly, efficient and fair to all parties. In addition, because the fee for our services is in most instances directly linked to the savings realized by our customers, our interests are aligned with the interests of our customers.

MultiPlan Corporation is a Delaware corporation. Our principal executive offices are located at 115 Fifth Avenue, New York, New York 10003 and our telephone number at that address is (212) 780-2000. Our website is located at www.multiplan.us. Our website and the information contained on, or accessed through, our website are not part of this prospectus, and you should rely only on the information contained in this prospectus when making an investment decision.

MultiPlan, formerly known as Churchill Capital Corp III (formerly known as Butler Acquisition Corp), was incorporated in Delaware on October 30, 2019 for the purpose of effecting a merger, capital stock exchange, asset acquisition, stock purchase, reorganization or similar business combination with one or more businesses.

On July 12, 2020, Churchill entered into the Merger Agreement by and among First Merger Sub, Second Merger Sub, Holdings, and MultiPlan Parent. On October 8, 2020, the Merger Agreement was consummated and the Transactions were completed. In connection with the Transactions, Churchill changed its name to MultiPlan Corporation and The New York Stock Exchange ticker symbols for its Class A common stock and warrants to "MPLN" and "MPLN.WS," respectively.

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RISK FACTORS

An investment in our securities involves a high degree of risk. Before investing in our securities, you should carefully consider the risk factors incorporated by reference into this prospectus, including any reports we file with the SEC after the date of this prospectus that are incorporated herein by reference, as well as the risk factors and other information contained in any applicable prospectus supplement and any applicable free writing prospectus we file with the SEC. The market price of our securities could decline if one or more of these risks or uncertainties actually occur, causing you to lose all or part of your investment in our securities. See "Where You Can Find More Information" and "Incorporation by Reference" elsewhere in this prospectus.

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USE OF PROCEEDS

All of the shares of Class A common stock offered by the Selling Securityholders pursuant to this prospectus will be sold by the Selling Securityholders for their respective accounts. We will not receive any of the proceeds from these sales.

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SELLING SECURITYHOLDERS

This prospectus relates to the resale by the Selling Securityholders from time to time of up to 130,000,000 shares of Class A common stock issuable by us upon conversion of the Notes.

On July 12, 2020, we entered into the Convertible Subscription Agreement with certain investors, pursuant to which we agreed to sell the Notes pursuant to the terms of an indenture between us and Wilmington Trust, National Association, dated as of October 8, 2020 (the "Indenture"). The Notes were initially convertible into an aggregate of 100,000,030 shares of Class A common stock and were issued in a transaction exempt from the registration requirements of the Securities Act. In addition, we entered into a registration rights agreement with certain investors, dated October 8, 2020 (the "Registration Rights Agreement"), pursuant to which we agreed to use commercially reasonable efforts to file a shelf registration statement with the SEC on or prior to December 8, 2021 providing for the registration and sale of the shares issuable upon conversion of the Notes. We have agreed to cause such registration statement to become effective on or prior to April 8, 2022 and use commercially reasonable efforts to keep the shelf registration statement effective to and including the earlier of (a) the twentieth (20th) trading day immediately following October 15, 2027 (subject to extension) and (b) the date (i) that is the twentieth (20th) trading day immediately following the date on which there are no longer outstanding any Notes or (ii) on which there are no longer outstanding any registrable securities (as defined in the Registration Rights Agreement).

The Selling Securityholders may from time to time offer and sell any or all of the Class A common stock set forth in any accompanying prospectus supplement. When we refer to the "Selling Securityholders" in this prospectus, we mean the persons listed as such in any accompanying prospectus supplement, and their permitted transferees who later come to hold any of the Selling Securityholders' interest in the Class A common stock in accordance with the terms of the agreement governing the registration rights applicable to such Selling Securityholder's shares of Class A common stock.

Any accompanying prospectus supplement shall set forth, as of the date of such accompanying prospectus supplement, the names of the Selling Securityholders, the number of shares of Class A common stock beneficially owned, the number of shares of Class A common stock that the Selling Securityholders may offer pursuant to this prospectus and the accompanying prospectus supplement and the number of shares of Class A common stock beneficially owned by the Selling Securityholders after the sale of the securities offered thereby.

The number of shares of Class A common stock that may be offered pursuant to this prospectus and the accompanying prospectus supplement will be calculated based on the initial conversion rate of 76.9231 shares of Class A common stock per $1,000 aggregate principal amount of Notes. The number of shares of Class A common stock issuable upon conversion of the Notes is subject to adjustment under certain circumstances described in the Indenture. Accordingly, the number of shares of Class A common stock issuable upon conversion of the Notes and the number of shares of Class A common stock beneficially owned and offered by the Selling Securityholders pursuant to this prospectus and the accompanying prospectus supplement may increase or decrease from that set forth in such accompanying prospectus supplement.

We have determined beneficial ownership in accordance with the rules of the SEC and the information is not necessarily indicative of beneficial ownership for any other purpose. Unless otherwise indicated in any accompanying prospectus supplement, to our knowledge, the persons and entities named in such accompanying prospectus supplement have sole voting and sole investment power with respect to all securities that they beneficially own, subject to community property laws where applicable.

We cannot advise you as to whether the Selling Securityholders will in fact sell any or all of such Class A common stock. In addition, the Selling Securityholders may sell, transfer or otherwise dispose of, at any time and from time to time, the Class A common stock in transactions exempt from the registration requirements of the Securities Act after the date of this prospectus. For purposes of this table, we have assumed that the Selling Securityholders will have sold all of the securities covered by this prospectus upon the completion of the offering.

Selling Securityholder information will be set forth by prospectus supplement to the extent required prior to the time of any offer or sale of such Selling Securityholder's shares pursuant to this prospectus and such prospectus supplement. Any prospectus supplement may add, update, substitute, or change the information contained in this

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prospectus, including the identity of each Selling Securityholder and the number of shares registered on its behalf. A Selling Securityholder may sell or otherwise transfer all, some or none of such shares in this offering. See "Plan of Distribution."

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DESCRIPTION OF SECURITIES

The following summary of the material terms of our securities is not intended to be a complete summary of the rights and preferences of such securities and is qualified in its entirety by our second amended and restated certificate of incorporation and amended and restated bylaws. The full text of our second amended and restated certificate of incorporation and amended and restated bylaws are incorporated by reference herein. For a complete description of the rights and preferences of our securities, we urge you to read our second amended and restated certificate of incorporation, amended and restated bylaws and the applicable provisions of Delaware law.

Authorized and Outstanding Stock

Our second amended and restated certificate of incorporation authorizes the issuance of shares of our capital stock, each with a par value of $0.0001, consisting of (a) 1,500,000,000 shares of Class A common stock and (b) 10,000,000 shares of preferred stock. The outstanding shares of Class A common stock are, and the shares of common stock issuable upon exercise of the Public Warrants, the PIPE Warrants and the Private Placement Warrants and upon conversion of the Notes will be, duly authorized, validly issued, fully paid and non-assessable.

As of September 30, 2021, there were (i) 645,847,578 shares of our Class A common stock outstanding excluding the 19,463,527 shares held by the Company as treasury shares, (ii) no shares of preferred stock outstanding, (iii) 27,500,000 shares of Class A common stock issuable upon the exercise of the Public Warrants, (iv) 23,000,000 shares of Class A common stock issuable upon the exercise of the Private Placement Warrants, (v) 1,500,000 shares of Class A common stock issuable upon the exercise of the Working Capital Warrants, (vi) 6,500,000 shares of Class A common stock issuable upon the exercise of the PIPE Warrants and (vii) 5,408,568 common stock issuable upon vesting or exercise, as applicable, of outstanding equity awards under our 2020 Omnibus Incentive Plan.

Voting Power

Except as otherwise required by law or as otherwise provided in any certificate of designation for any series of preferred stock, under our second amended and restated certificate of incorporation, the holders of common stock will possess all voting power for the election of directors and all other matters requiring stockholder action and will be entitled to one vote per share on matters to be voted on by stockholders. The holders of our Class A common stock will at all times vote together as one class on all matters submitted to a vote of the common stock under the second amended and restated certificate of incorporation.

Dividends

Subject to the rights, if any, of the holders of any outstanding shares of preferred stock, under our second amended and restated certificate of incorporation, holders of our Class A common stock will be entitled to receive such dividends and other distributions, if any, as may be declared from time to time by the Board in its discretion out of funds legally available therefor and shall share equally on a per share basis in such dividends and distributions.

Liquidation, Dissolution and Winding Up

In the event of the voluntary or involuntary liquidation, dissolution, or winding-up of the Company, the holders of our Class A common stock will be entitled to receive all the remaining assets of the Company available for distribution to stockholders, ratably in proportion to the number of shares of Class A common stock held by them, after the rights of creditors of the Company and the holders of any outstanding shares of preferred stock have been satisfied.

Preemptive or Other Rights

The holders of our Class A common stock do not have preemptive or other subscription rights and there is no sinking fund or redemption provisions applicable to our Class A common stock.

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Preferred Stock

Our second amended and restated certificate of incorporation authorizes 10,000,000 shares of preferred stock and provides that shares of preferred stock may be issued from time to time in one or more series. The Board is authorized to fix the voting rights, if any, designations, powers, preferences, the relative, participating, optional or other special rights and any qualifications, limitations and restrictions thereof, applicable to the shares of each series. The Board is be able to, without stockholder approval, issue preferred stock with voting and other rights that could adversely affect the voting power and other rights of the holders of the common stock and could have anti-takeover effects. The ability of the Board is to issue preferred stock without stockholder approval could have the effect of delaying, deferring or preventing a change of control of us or the removal of existing management. Although we do not currently intend to issue any shares of preferred stock, we cannot assure you that we will not do so in the future.

Registration Rights

Pursuant to the Registration Rights Agreement, the holders of the Notes are entitled to customary registration rights with respect to the shares of Class A common stock issuable upon conversion of the Notes. Pursuant to the Registration Rights Agreement, we agreed to use commercially reasonable efforts to file a shelf registration statement with the SEC on or prior to December 8, 2021 providing for the registration and sale of the shares issuable upon conversion of the Notes. We have agreed to cause such registration statement to become effective on or prior to April 8, 2022 and use commercially reasonable efforts to keep the shelf registration statement effective to and including the earlier of (a) the twentieth (20th) trading day immediately following October 15, 2027 (subject to extension) and (b) the date (i) that is the twentieth (20th) trading day immediately following the date on which there are no longer outstanding any Notes or (ii) on which there are no longer outstanding any registrable securities (as defined in the Registration Rights Agreement). We have agreed to pay all expenses incurred in connection with the registration of such shares, including the fees and expenses of counsel to the holders of the Notes related to the review of the shelf registration statement and any supplements or amendments thereto. The foregoing summary of the Registration Rights Agreement is not complete and is qualified in its entirety by the full text of the Registration Rights Agreement, which is incorporated by reference herein.

Annual Stockholder Meetings

Our second amended and restated certificate of incorporation and amended and restated bylaws provide that annual stockholder meetings will be held at a date, time and place, if any, as exclusively selected by the Board. To the extent permitted under applicable law, we may conduct meetings by remote communications, including by webcast.

Effects of Our Second Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws and Certain Provisions of Delaware Law

Our second amended and restated certificate of incorporation, amended and restated bylaws and the DGCL contain provisions, which are summarized in the following paragraphs, that are intended to enhance the likelihood of continuity and stability in the composition of the Board. These provisions are intended to avoid costly takeover battles, reduce our vulnerability to a hostile change of control and enhance the ability of the Board to maximize stockholder value in connection with any unsolicited offer to acquire us. However, these provisions may have the effect of delaying, deterring or preventing a merger or acquisition of the Company by means of a tender offer, a proxy contest or other takeover attempt that a stockholder might consider in its best interest, including attempts that might result in a premium over the prevailing market price for the shares of our Class A common stock held by stockholders.

Authorized but Unissued Capital Stock

Delaware law does not require stockholder approval for any issuance of authorized shares. However, the listing requirements of the NYSE, which would apply if and so long as our Class A common stock remains listed on the NYSE, require stockholder approval of certain issuances equal to or exceeding 20% of the then outstanding voting power or then outstanding number of shares of our Class A common stock. Additional shares that may be

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used in the future may be used for a variety of corporate purposes, including future public offerings, to raise additional capital or to facilitate acquisitions.

The Board may generally issue one or more series of preferred shares on terms calculated to discourage, delay or prevent a change of control of the Company or the removal of our management. Moreover, our authorized but unissued shares of preferred stock will be available for future issuances in one or more series without stockholder approval and could be utilized for a variety of corporate purposes, including future offerings to raise additional capital, to facilitate acquisitions and employee benefit plans.

One of the effects of the existence of authorized and unissued and unreserved common stock or preferred stock may be to enable the Board to issue shares to persons friendly to current management, which issuance could render more difficult or discourage an attempt to obtain control of the Company by means of a merger, tender offer, proxy contest or otherwise, and thereby protect the continuity of our management and possibly deprive our stockholders of opportunities to sell their shares of Class A common stock at prices higher than prevailing market prices.

Classified Board of Directors

Our second amended and restated certificate of incorporation provides that, subject to the right of holders of any series of preferred stock, the Board will be divided into three classes of directors, with the classes to be as nearly equal in number as possible, and with the directors serving staggered three-year terms, with only one class of directors being elected at each annual meeting of stockholders. As a result, approximately one-third of the Board will be elected each year. The classification of directors will have the effect of making it more difficult for stockholders to change the composition of the Board. Our second amended and restated certificate of incorporation and amended and restated bylaws provide that, subject to the Investor Rights Agreement or any rights of holders of preferred stock to elect additional directors under specified circumstances, the number of directors will be fixed from time to time exclusively pursuant to a resolution adopted by the Board; however, any determination by the Board to increase or decrease the total number of directors shall require the approval of 66 2/3% of the directors present at a meeting at which a quorum is present.

Business Combinations

We have opted out of Section 203 of the DGCL; however, our second amended and restated certificate of incorporation contains similar provisions providing that we may not engage in certain "business combinations" with any "interested stockholder" for a three-year period following the time that the stockholder became an interested stockholder, unless:

•prior to such time, the Board approved either the business combination or the transaction that resulted in the stockholder becoming an interested stockholder;

•upon consummation of the transaction which resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of our voting stock outstanding at the time the transaction commenced, excluding certain shares;

•at or subsequent to that time, the business combination is approved by the Board and by the affirmative vote of holders of at least 66 2/3% of our outstanding voting stock that is not owned by the interested stockholder; or

•the stockholder became an interested stockholder inadvertently and (i) as soon as practicable divested itself of sufficient ownership to cease to be an interested stockholder and (ii) had not been an interested stockholder but for the inadvertent acquisition of ownership within three years of the business combination.

Generally, a "business combination" includes a merger, asset or stock sale or other transaction resulting in a financial benefit to the interested stockholder. Subject to certain exceptions, an "interested stockholder" is a person who, together with that person's affiliates and associates, owns, or within the previous three years owned, 15% or

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more of our outstanding voting stock. For purposes of this section only, "voting stock" has the meaning given to it in Section 203 of the DGCL.

Under certain circumstances, this provision will make it more difficult for a person who would be an "interested stockholder" to effect various business combinations with the Company for a three-year period. This provision may encourage companies interested in acquiring the Company to negotiate in advance with the Board because the stockholder approval requirement would be avoided if the Board approves either the business combination or the transaction which results in the stockholder becoming an interested stockholder. These provisions also may have the effect of preventing changes in the Board and may make it more difficult to accomplish transactions that stockholders may otherwise deem to be in their best interests.

Our second amended and restated certificate of incorporation provides that Hellman & Friedman LLC (together with its affiliates, subsidiaries, successors and assigns (other than the Company and its subsidiaries)), any of its direct transferees, any of their respective affiliates or successors, and any group as to which such persons or entities are a party, does not constitute an "interested stockholder" for purposes of this provision.

Removal of Directors; Vacancies

Under the DGCL, unless otherwise provided in our second amended and restated certificate of incorporation, directors serving on a classified board may be removed by the stockholders only for cause.

Our second amended and restated certificate of incorporation provides that, without limiting the rights of any party to the Investor Rights Agreement and other than directors elected by holders of our preferred stock, if any, directors may be removed with or without cause upon the affirmative vote of a majority in voting power of all outstanding shares of stock entitled to vote thereon, voting together as a single class; provided, however, at any time when the Sellers and their Permitted Transferees (each as defined in the Investor Rights Agreement) beneficially own less than 50% in voting power of the stock of the Company entitled to vote generally in the election of directors, directors may only be removed for cause, and only by the affirmative vote of holders of at least 66 2/3% in voting power of all the then-outstanding shares of stock of the Company entitled to vote thereon, voting together as a single class. In addition, our second amended and restated certificate of incorporation provides that, without limiting the rights of any party to the Investor Rights Agreement, any newly created directorship on the Board that results from an increase in the number of directors and any vacancies on the Board will be filled only by the affirmative vote of a majority of the remaining directors, even if less than a quorum, or by a sole remaining director or by the stockholders; provided, however, at any time when the Sellers and their Permitted Transferees beneficially own less than 50% in voting power of the stock of the Company entitled to vote generally in the election of directors, any newly created directorship on the Board that results from an increase in the number of directors and any vacancy occurring in the Board may only be filled by a majority of the directors then in office, even if less than a quorum, or by a sole remaining director (and not by the stockholders). Our second amended and restated certificate of incorporation provides that the Board may increase or decrease the number of directors by the affirmative vote of 66 2/3% of the directors present at the meeting at which a quorum is present.

No Cumulative Voting

Under Delaware law, the right to vote cumulatively does not exist unless the certificate of incorporation specifically authorizes cumulative voting. Our second amended and restated certificate of incorporation does not authorize cumulative voting. Therefore, stockholders holding a majority in voting power of the shares of our stock entitled to vote generally in the election of directors will be able to elect all of our directors.

Special Stockholder Meetings

Our second amended and restated certificate of incorporation provides that special meetings of our stockholders may be called at any time only by or at the direction of the Board or the chairman of the Board. Our amended and restated bylaws prohibit the conduct of any business at a special meeting other than as specified in the notice for such meeting. These provisions may have the effect of deferring, delaying or discouraging hostile takeovers, or changes in control or management of the Company.

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Requirements for Advance Notification of Director Nominations and Stockholder Proposals

Our amended and restated bylaws establish advance notice procedures with respect to stockholder proposals and the nomination of candidates for election as directors, other than nominations made by or at the direction of the Board or a committee of the Board. In order for any matter to be properly brought before a meeting of our stockholders, a stockholder will have to comply with advance notice requirements and provide us with certain information. Generally, to be timely, a stockholder's notice must be received by our secretary not less than 90 calendar days nor more than 120 calendar days prior to the first anniversary date of the immediately preceding annual meeting of stockholders (which, for 2021, is deemed to be May 26, 2021). Our amended and restated bylaws also specify requirements as to the form and content of a stockholder's notice. Our amended and restated bylaws allow the chairman of the meeting at a meeting of the stockholders to adopt rules and regulations for the conduct of meetings, which may have the effect of precluding the conduct of certain business at a meeting if the rules and regulations are not followed. These provisions may also deter, delay or discourage a potential acquirer from conducting a solicitation of proxies to elect the acquirer's own slate of directors or otherwise attempting to influence or obtain control of the Company.

Stockholder Action by Written Consent

Pursuant to Section 228 of the DGCL, any action required to be taken at any annual or special meeting of the stockholders may be taken without a meeting, without prior notice and without a vote if a consent or consents in writing, setting forth the action so taken, is signed by the holders of outstanding stock having not less than the minimum number of votes that would be necessary to authorize or take such action at a meeting at which all shares of our stock entitled to vote thereon were present and voted, unless our second amended and restated certificate of incorporation provides otherwise. Our second amended and restated certificate of incorporation precludes stockholder action by written consent at any time when the Sellers and their Permitted Transferees beneficially own less than 50% in voting power of the stock of the Company entitled to vote generally in the election of directors, other than certain rights that holders of our preferred stock may have to act by written consent.

Supermajority Provisions

Our second amended and restated certificate of incorporation and amended and restated bylaws provide that the Board is expressly authorized to make, alter, amend, change, add to, rescind or repeal, in whole or in part, our bylaws without a stockholder vote in any matter not inconsistent with Delaware law, our second amended and restated certificate of incorporation or the Investor Rights Agreement. At any time when the Sellers and their Permitted Transferees beneficially own less than 50% in voting power of all outstanding shares of the stock of the Company entitled to vote generally in the election of directors, any amendment, alteration, rescission, change, addition or repeal of our bylaws by our stockholders will require the affirmative vote of the holders of at least 66 2/3% in voting power of all the then-outstanding shares of stock of the Company entitled to vote thereon, voting together as a single class.

The DGCL provides generally that the affirmative vote of a majority of the outstanding shares entitled to vote thereon, voting together as a single class, is required to amend a corporation's certificate of incorporation, unless the certificate of incorporation requires a greater percentage.

Our second amended and restated certificate of incorporation provides that at any time when the Sellers and their Permitted Transferees beneficially own less than 50% in voting power of the stock of the Company entitled to vote generally in the election of directors, in addition to any vote required by applicable law, the following provisions in our second amended and restated certificate of incorporation may be amended, altered, repealed or rescinded, in whole or in part, or any provision inconsistent therewith may be adopted, only by the affirmative vote of the holders of at least 66 2/3% in voting power of all the then-outstanding shares of stock of the Company entitled to vote thereon, voting together as a single class:

•the provision requiring a 66 2/3% supermajority vote for stockholders to amend our second amended and restated bylaws;

•the provisions providing for a classified board of directors (the election and term of our directors);

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•the provisions regarding resignation and removal of directors;

•the provisions regarding competition and corporate opportunities;

•the provisions regarding filling vacancies on the Board and newly created directorships; and

•the amendment provision requiring that the above provisions be amended only with a 66 2/3% supermajority vote.

The combination of the classification of the Board, the lack of cumulative voting and the supermajority voting requirements will make it more difficult for our existing stockholders to replace the Board as well as for another party to obtain control of us by replacing the Board. Because the Board has the power to retain and discharge our officers, these provisions could also make it more difficult for existing stockholders or another party to effect a change in management.

These provisions may have the effect of deterring hostile takeovers or delaying or preventing changes in control of our management or the Company, such as a merger, reorganization or tender offer. These provisions are intended to enhance the likelihood of continued stability in the composition of the Board and its policies and to discourage certain types of transactions that may involve an actual or threatened acquisition of the Company. These provisions are designed to reduce our vulnerability to an unsolicited acquisition proposal. These provisions are also intended to discourage certain tactics that may be used in proxy fights. However, such provisions could have the effect of discouraging others from making tender offers for our shares and, as a consequence, they also may inhibit fluctuations in the market price of our shares that could result from actual or rumored takeover attempts. Such provisions may also have the effect of preventing changes in management of the Company.

Dissenters' Rights of Appraisal and Payment

Under the DGCL, with certain exceptions, our stockholders will have appraisal rights in connection with a merger or consolidation of us. Pursuant to the DGCL, stockholders who properly request and perfect appraisal rights in connection with such merger or consolidation will have the right to receive payment of the fair value of their shares as determined by the Delaware Court of Chancery.

Stockholders' Derivative Actions

Under the DGCL, any of our stockholders may bring an action in our name to procure a judgment in our favor, also known as a derivative action, provided that the stockholder bringing the action is a holder of our shares at the time of the incident to which the action relates or such stockholder's stock thereafter devolved by operation of law.

Exclusive Forum

Our second amended and restated certificate of incorporation provides that unless the Company consents in writing to the selection of an alternative forum, a state court located within the State of Delaware (or if no state court located within the State of Delaware has jurisdiction, the federal district court for the District of Delaware) shall be the sole and exclusive forum for any (i) derivative action or proceeding brought on behalf of the Company, (ii) action asserting a claim of breach of a fiduciary duty owed by any director, officer or other employee of the Company to the Company or the Company's stockholders, (iii) action asserting a claim against the Company or any director, officer or other employee of the Company arising pursuant to any provision of the DGCL or our second amended and restated certificate of incorporation or our amended and restated bylaws (as either may be amended, restated, modified, supplemented or waived from time to time), (iv) action asserting a claim against the Company or any director, officer or other employee of the Company governed by the internal affairs doctrine, or (v) action asserting an "internal corporate claim" as that term is defined in Section 115 of the DGCL. These provisions shall not apply to suits brought to enforce a duty or liability created by the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction. Unless the Company consents in writing to the selections of an alternative forum, the federal district courts of the United States of America shall be the exclusive forum for the resolution of any complaint asserting a cause of action arising under the Securities Act. Any person or entity purchasing or

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otherwise acquiring any interest in shares of capital stock of the Company shall be deemed to have notice of and consented to the forum provisions in our second amended and restated certificate of incorporation. However, it is possible that a court could find our forum selection provisions to be inapplicable or unenforceable.

Conflicts of Interest

Delaware law permits corporations to adopt provisions renouncing any interest or expectancy in certain opportunities that are presented to the corporation or its officers, directors or stockholders. Our second amended and restated certificate of incorporation renounces, to the maximum extent permitted from time to time by Delaware law, any interest or expectancy that we have in, or right to be offered an opportunity to participate in, any business opportunities that are from time to time presented to our officers, directors or stockholders or their respective affiliates, other than those officers, directors, stockholders or affiliates who are our or our subsidiaries' employees. Our second amended and restated certificate of incorporation provides that, to the fullest extent permitted by law, none of any Seller, Churchill or any director who is not employed by us (including any non-employee director who serves as one of our officers in both his director and officer capacities) or his or her affiliates will have any duty to refrain from (i) engaging in and possessing interests in other business ventures of every type and description, including corporate opportunities in the same or similar business activities or lines of business in which we or our subsidiaries now engage or propose to engage or (ii) competing with us or any of our subsidiaries, on their own account, or in partnership with, or as an employee, officer, director or shareholder of any other person. In addition, to the fullest extent permitted by law, in the event that any Seller, Churchill or any non-employee director acquires knowledge of a potential transaction or other matter which may be a corporate or other business opportunity for itself or himself, or herself, or its or his, or her, affiliates or for us or our affiliates, such person will have no duty (fiduciary, contractual or otherwise) to communicate or present such transaction or matter to us or any of our subsidiaries or any Seller, as the case may be, and they may take any such opportunity for themselves or direct it to another person or entity. Our second amended and restated certificate of incorporation will not renounce our interest in any business opportunity that is expressly offered to a non-employee director solely in his or her capacity as a director or officer of the Company. To the fullest extent permitted by law, no business opportunity will be deemed to be a potential corporate opportunity for us unless we would be permitted to undertake the opportunity under our amended and restated certificate of incorporation, we have sufficient financial resources to undertake the opportunity and the opportunity would be in line with our business.

Indemnification of Directors and Officers

Section 102(b)(7) of the DGCL allows a corporation to provide in its certificate of incorporation that a director of the corporation will not be personally liable to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except where the director breached the duty of loyalty, failed to act in good faith, engaged in intentional misconduct or knowingly violated a law, authorized the payment of a dividend or approved a stock repurchase in violation of Delaware corporate law or obtained an improper personal benefit. Our second amended and restated certificate of incorporation provides for this limitation of liability.

Section 145 of the DGCL, provides, among other things, that a Delaware corporation may indemnify any person who was, is or is threatened to be made, party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of such corporation), by reason of the fact that such person is or was an officer, director, employee or agent of such corporation or is or was serving at the request of such corporation as a director, officer, employee or agent of another corporation or enterprise. The indemnity may include expenses (including attorneys' fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by such person in connection with such action, suit or proceeding, provided such person acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the corporation's best interests and, with respect to any criminal action or proceeding, had no reasonable cause to believe that his or her conduct was unlawful. A Delaware corporation may indemnify any persons who were or are a party to any threatened, pending or completed action or suit by or in the right of the corporation by reason of the fact that such person is or was a director, officer, employee or agent of another corporation or enterprise. The indemnity may include expenses (including attorneys' fees) actually and reasonably incurred by such person in connection with the defense or settlement of such action or suit, provided such person acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the corporation's best interests, provided further that no indemnification is permitted without judicial approval if the officer, director, employee or agent is

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adjudged to be liable to the corporation. Where an officer or director is successful on the merits or otherwise in the defense of any action referred to above, the corporation must indemnify him or her against the expenses (including attorneys' fees) which such officer or director has actually and reasonably incurred.

Section 145 further authorizes a corporation to purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the corporation or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation or enterprise, against any liability asserted against such person and incurred by such person in any such capacity, or arising out of his or her status as such, whether or not the corporation would otherwise have the power to indemnify such person under Section 145.

Our amended and restated bylaws provide that we must indemnify and advance expenses to our directors and officers to the full extent authorized by the DGCL.

We have entered into indemnification agreements with each of our directors and executive officers. Such agreements may require us, among other things, to advance expenses and otherwise indemnify our executive officers and directors against certain liabilities that may arise by reason of their status or service as executive officers or directors, to the fullest extent permitted by law. We intend to enter into indemnification agreements with any new directors and executive officers in the future.

The indemnification rights set forth above shall not be exclusive of any other right which an indemnified person may have or hereafter acquire under any statute, any provision of the Company's second amended and restated certificate of incorporation, the Company's second amended and restated bylaws, agreement, vote of stockholders or disinterested directors or otherwise. Notwithstanding the foregoing, the Company shall not be obligated to indemnify a director or officer in respect of a proceeding (or part thereof) instituted by such director or officer, unless such proceeding (or part thereof) has been authorized by the Board pursuant to the applicable procedure outlined in the Company's second amended and restated bylaws.

Section 174 of the DGCL provides, among other things, that a director, who willfully or negligently approves of an unlawful payment of dividends or an unlawful stock purchase or redemption, may be held jointly and severally liable for such actions. A director who was either absent when the unlawful actions were approved or dissented at the time may avoid liability by causing his or her dissent to such actions to be entered in the books containing the minutes of the meetings of the board of directors at the time such action occurred or immediately after such absent director receives notice of the unlawful acts.

The Company maintains and expect to maintain standard policies of insurance that provide coverage (1) to its directors and officers against loss rising from claims made by reason of breach of duty or other wrongful act and (2) to the Company with respect to indemnification payments that the Company may make to such directors and officers.

These provisions may discourage stockholders from bringing a lawsuit against our directors for breach of their fiduciary duty. These provisions also may have the effect of reducing the likelihood of derivative litigation against directors and officers, even though such an action, if successful, might otherwise benefit the Company and our stockholders. Furthermore, a stockholder's investment may be adversely affected to the extent we pay the costs of settlement and damage awards against officers and directors pursuant to these indemnification provisions.

The Company believes that these provisions, the insurance and the indemnity agreements are necessary to attract and retain talented and experienced officers and directors.

Dividends

We have not paid any cash dividends on our common stock to date. The payment of cash dividends in the future will be dependent upon our revenues and earnings, if any, capital requirements, the terms of any outstanding indebtedness and our general financial condition. The payment of any cash dividends will be within the discretion of the Board at such time. In addition, the Board is not currently contemplating and does not anticipate declaring any stock dividends in the foreseeable future. Further, if we incur any indebtedness, our ability to declare dividends may be limited by restrictive covenants we may agree to in connection therewith.

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Our Transfer Agent

The transfer agent for our common stock is Continental Stock Transfer & Trust Company. We have agreed to indemnify Continental Stock Transfer & Trust Company in its role as transfer agent, its agents and each of its stockholders, directors, officers and employees against all liabilities, including judgments, costs and reasonable counsel fees that may arise out of acts performed or omitted for its activities in that capacity, except for any liability due to any gross negligence, willful misconduct or bad faith of the indemnified person or entity.

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CERTAIN UNITED STATES FEDERAL INCOME TAX CONSEQUENCES TO NON-U.S. HOLDERS

The following is a summary of certain United States federal income tax consequences of the ownership and disposition of our Class A common stock. This summary deals only with Class A common stock that is held as a capital asset by a non-U.S. holder (as defined below) that purchases the Class A common stock in this offering for cash.

A "non-U.S. holder" means a beneficial owner of our Class A common stock (other than an entity or arrangement treated as a partnership for United States federal income tax purposes) that is not, for United States federal income tax purposes, any of the following:

•an individual who is a citizen or resident of the United States;

•a corporation (or any other entity treated as a corporation for United States federal income tax purposes) that is created or organized in or under the laws of the United States, any state thereof or the District of Columbia;

•an estate the income of which is subject to United States federal income taxation regardless of its source; or

•a trust if it (i) is subject to the primary supervision of a court within the United States and one or more United States persons have the authority to control all substantial decisions of the trust or (ii) has a valid election in effect under applicable United States Treasury regulations to be treated as a United States person.

This summary is based upon provisions of the Internal Revenue Code of 1986, as amended (the "Code"), and regulations, rulings and judicial decisions as of the date hereof. Those authorities are subject to different interpretations and may be changed, perhaps retroactively, so as to result in United States federal income tax consequences different from those summarized below. This summary does not address all of the United States federal income tax consequences that may be relevant to you in light of your particular circumstances, nor does it address the Medicare tax on net investment income, United States federal estate and gift taxes or the effects of any state, local or non-United States tax laws. In addition, it does not represent a detailed description of the United States federal income tax consequences applicable to you if you are subject to special treatment under the United States federal income tax laws (including if you are a United States expatriate, a foreign pension fund, a financial institution, an insurance company, a tax-exempt organization, a trader, broker or dealer in securities, a "controlled foreign corporation," a "passive foreign investment company," a partnership or other pass-through entity for United States federal income tax purposes (or an investor in such a pass-through entity), a person who acquired shares of our Class A common stock as compensation or otherwise in connection with the performance of services, or a person who holds shares of our Class A common stock as part of a straddle, hedge, conversion transaction or other integrated investment). We cannot assure you that a change in law will not alter significantly the tax considerations that we describe in this summary.

If a partnership (or other entity or arrangement treated as a partnership for United States federal income tax purposes) holds our Class A common stock, the tax treatment of a partner will generally depend upon the status of the partner and the activities of the partnership. If you are a partnership or a partner of a partnership holding our Class A common stock, you should consult your tax advisors.

If you are considering the purchase of our Class A common stock, you should consult your own tax advisors concerning the particular United States federal income tax consequences to you of the ownership and disposition of our Class A common stock, as well as the consequences to you arising under other United States federal tax laws and the laws of any other taxing jurisdiction.

Dividends

In the event that we make a distribution of cash or other property (other than certain pro rata distributions of our stock) in respect of our Class A common stock, the distribution generally will be treated as a dividend for

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United States federal income tax purposes to the extent it is paid from our current or accumulated earnings and profits, as determined under United States federal income tax principles. Any portion of a distribution that exceeds our current and accumulated earnings and profits generally will be treated first as a tax-free return of capital, causing a reduction in the adjusted tax basis of a non-U.S. holder's Class A common stock, and to the extent the amount of the distribution exceeds a non-U.S. holder's adjusted tax basis in our Class A common stock, the excess will be treated as gain from the disposition of our Class A common stock (the tax treatment of which is discussed below under "- Gain on Disposition of Class A Common Stock").

Dividends paid to a non-U.S. holder generally will be subject to withholding of United States federal income tax at a 30% rate or such lower rate as may be specified by an applicable income tax treaty. However, dividends that are effectively connected with the conduct of a trade or business by the non-U.S. holder within the United States (and, if required by an applicable income tax treaty, are attributable to a United States permanent establishment) are not subject to the withholding tax, provided certain certification and disclosure requirements are satisfied. Instead, such dividends are subject to United States federal income tax on a net income basis generally in the same manner as if the non-U.S. holder were a United States person as defined under the Code. Any such effectively connected dividends received by a foreign corporation may be subject to an additional "branch profits tax" at a 30% rate or such lower rate as may be specified by an applicable income tax treaty.

A non-U.S. holder who wishes to claim the benefit of an applicable treaty rate and avoid backup withholding, as discussed below, for dividends will be required (a) to provide the applicable withholding agent with a properly executed Internal Revenue Service ("IRS") Form W-BEN or Form W-8BEN-E (or other applicable form) certifying under penalty of perjury that such holder is not a United States person as defined under the Code and is eligible for treaty benefits or (b) if our Class A common stock is held through certain foreign intermediaries, to satisfy the relevant certification requirements of applicable United States Treasury regulations. Special certification and other requirements apply to certain non-U.S. holders that are pass-through entities rather than corporations or individuals.

A non-U.S. holder eligible for a reduced rate of United States federal withholding tax pursuant to an income tax treaty may obtain a refund of any excess amounts withheld by timely filing an appropriate claim for refund with the IRS.

Gain on Disposition of Class A Common Stock

Subject to the discussion of backup withholding below, any gain realized by a non-U.S. holder on the sale or other disposition of our Class A common stock generally will not be subject to United States federal income tax unless:

•the gain is effectively connected with a trade or business of the non-U.S. holder in the United States (and, if required by an applicable income tax treaty, is attributable to a United States permanent establishment of the non-U.S. holder);

•the non-U.S. holder is an individual who is present in the United States for 183 days or more in the taxable year of that disposition, and certain other conditions are met; or

•we are or have been a "United States real property holding corporation" for United States federal income tax purposes and certain other conditions are met.

A non-U.S. holder described in the first bullet point immediately above will be subject to tax on the gain derived from the sale or other disposition in the same manner as if the non-U.S. holder were a United States person as defined under the Code. In addition, if any non-U.S. holder described in the first bullet point immediately above is a foreign corporation, the gain realized by such non-U.S. holder may be subject to an additional "branch profits tax" at a 30% rate or such lower rate as may be specified by an applicable income tax treaty. An individual non-U.S. holder described in the second bullet point immediately above will be subject to a 30% (or such lower rate as may be specified by an applicable income tax treaty) tax on the gain derived from the sale or other disposition, which gain may be offset by United States source capital losses even though the individual is not considered a resident of the United States.

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Generally, a corporation is a "United States real property holding corporation" if the fair market value of its United States real property interests equals or exceeds 50% of the sum of the fair market value of its worldwide real property interests and its other assets used or held for use in a trade or business (all as determined for United States federal income tax purposes). We believe we are not and do not anticipate becoming a "United States real property holding corporation" for United States federal income tax purposes.

Information Reporting and Backup Withholding

Distributions paid to a non-U.S. holder and the amount of any tax withheld with respect to such distributions generally will be reported to the IRS. Copies of the information returns reporting such distributions and any withholding may also be made available to the tax authorities in the country in which the non-U.S. holder resides under the provisions of an applicable income tax treaty.

A non-U.S. holder will not be subject to backup withholding on distributions received if such holder certifies under penalty of perjury that it is a non-U.S. holder (and the payor does not have actual knowledge or reason to know that such holder is a United States person as defined under the Code), or such holder otherwise establishes an exemption.

Information reporting and, depending on the circumstances, backup withholding will apply to the proceeds of a sale or other disposition of our Class A common stock made within the United States or conducted through certain United States-related financial intermediaries, unless the beneficial owner certifies under penalty of perjury that it is a non-U.S. holder (and the payor does not have actual knowledge or reason to know that the beneficial owner is a United States person as defined under the Code), or such owner otherwise establishes an exemption.

Backup withholding is not an additional tax and any amounts withheld under the backup withholding rules will be allowed as a refund or a credit against a non-U.S. holder's United States federal income tax liability provided the required information is timely furnished to the IRS.

Additional Withholding Requirements

Under Sections 1471 through 1474 of the Code (such Sections commonly referred to as "FATCA"), a 30% United States federal withholding tax may apply to any dividends paid on our Class A common stockto (i) a "foreign financial institution" (as specifically defined in the Code and whether such foreign financial institution is the beneficial owner or an intermediary) which does not provide sufficient documentation, typically on IRS Form W-8BEN-E, evidencing either (x) an exemption from FATCA, or (y) its compliance (or deemed compliance) with FATCA (which may alternatively be in the form of compliance with an intergovernmental agreement with the United States) in a manner which avoids withholding, or (ii) a "non-financial foreign entity" (as specifically defined in the Code and whether such non-financial foreign entity is the beneficial owner or an intermediary) which does not provide sufficient documentation, typically on IRS Form W-8BEN-E, evidencing either (x) an exemption from FATCA, or (y) adequate information regarding certain substantial United States beneficial owners of such entity (if any). If a dividend payment is both subject to withholding under FATCA and subject to the withholding tax discussed above under "- Dividends," an applicable withholding agent may credit the withholding under FATCA against, and therefore reduce, such other withholding tax. While withholding under FATCA would also have applied to payments of gross proceeds from the sale or other taxable disposition of our Class A common stock, proposed United States Treasury regulations (upon which taxpayers may rely until final regulations are issued) eliminate FATCA withholding on payments of gross proceeds entirely. You should consult your own tax advisors regarding these rules and whether they may be relevant to your ownership and disposition of our Class A common stock.

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PLAN OF DISTRIBUTION

We are registering the shares of Class A common stock issuable to the Selling Securityholders upon conversion of the Notes to permit the offer and sale of such shares of Class A common stock by the Selling Securityholders from time to time after the date of this prospectus.

We will not receive any of the proceeds from the sale of the securities by the Selling Securityholders. The aggregate proceeds to the Selling Securityholders will be the purchase price of the securities less any discounts and commissions borne by the Selling Securityholders.

The Selling Securityholders will pay any underwriting discounts and commissions and expenses incurred by the Selling Securityholders for brokerage, accounting, tax or legal services or any other expenses incurred by the Selling Securityholders in disposing of the securities.

We entered into the Registration Rights Agreement for the benefit of the holders of the Notes to register the shares of Class A common stock issuable upon conversion of the Notes for offer and resale under applicable federal securities laws under specific circumstances and at specific times. We will bear all other costs, fees and expenses incurred in effecting the registration of the securities covered by this prospectus, including, without limitation, all registration and filing fees, NYSE listing fees and fees and expenses of our counsel and our independent registered public accountants.

The securities beneficially owned by the Selling Securityholders covered by this prospectus may be offered and sold from time to time by the Selling Securityholders. The term "Selling Securityholders" includes their permitted transferees who later come to hold any of the Selling Securityholders' interest in the Class A common stock in accordance with the terms of the agreement governing the registration rights applicable to such Selling Securityholder's shares of Class A common stock. The Selling Securityholders will act independently of us in making decisions with respect to the timing, manner and size of each sale. Such sales may be made on one or more exchanges or in the over-the-counter market or otherwise, at prices and under terms then prevailing or at prices related to the then current market price or in negotiated transactions. Each Selling Securityholder reserves the right to accept and, together with its respective agents, to reject, any proposed purchase of securities to be made directly or through agents. The Selling Securityholders and any of their permitted transferees may sell their securities offered by this prospectus on any stock exchange, market or trading facility on which the securities are traded or in private transactions. If underwriters are used in the sale, such underwriters will acquire the shares for their own account. These sales may be at a fixed price or varying prices, which may be changed, or at market prices prevailing at the time of sale, at prices relating to prevailing market prices or at negotiated prices. The securities may be offered to the public through underwriting syndicates represented by managing underwriters or by underwriters without a syndicate.

Subject to the limitations set forth in any applicable registration rights agreement, the Selling Securityholders may use any one or more of the following methods when selling the securities offered by this prospectus:

•purchases by a broker-dealer as principal and resale by such broker-dealer for its own account pursuant to this prospectus;

•ordinary brokerage transactions and transactions in which the broker solicits purchasers;

•block trades in which the broker-dealer so engaged will attempt to sell the securities as agent but may position and resell a portion of the block as principal to facilitate the transaction;

•an over-the-counter distribution in accordance with the rules of NYSE;

•through trading plans entered into by a Selling Securityholder pursuant to Rule 10b5-1 under the Exchange Act that are in place at the time of an offering pursuant to this prospectus and any applicable prospectus supplement hereto that provide for periodic sales of their securities on the basis of parameters described in such trading plans;

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•through one or more underwritten offerings on a firm commitment or best efforts basis;

•settlement of short sales entered into after the date of this prospectus;

•agreements with broker-dealers to sell a specified number of the securities at a stipulated price per share or warrant;

•in "at the market" offerings, as defined in Rule 415 under the Securities Act, at negotiated prices, at prices prevailing at the time of sale or at prices related to such prevailing market prices, including sales made directly on a national securities exchange or sales made through a market maker other than on an exchange or other similar offerings through sales agents;

•directly to purchasers, including through a specific bidding, auction or other process or in privately negotiated transactions;

•through the writing or settlement of options or other hedging transactions, whether through an options exchange or otherwise;

•through a combination of any of the above methods of sale; or

•any other method permitted pursuant to applicable law.

There can be no assurance that the Selling Securityholders will sell all or any of the securities offered by this prospectus. In addition, the Selling Securityholders may also sell securities under Rule 144 under the Securities Act, if available, or in other transactions exempt from registration, rather than under this prospectus. The Selling Securityholders have the sole and absolute discretion not to accept any purchase offer or make any sale of securities if they deem the purchase price to be unsatisfactory at any particular time.

Subject to the terms of the agreement governing the registration rights applicable to a Selling Securityholder's shares of Class A common stock, such Selling Securityholder may transfer shares of Class A common stock to one or more "permitted transferees" in accordance with such agreements and, if so transferred, such permitted transferee(s) will be the selling beneficial owner(s) for purposes of this prospectus. Upon being notified by a Selling Securityholder interest intends to sell our securities, we will, to the extent required, promptly file a supplement to this prospectus to name specifically such person as a Selling Securityholder.

With respect to a particular offering of the securities held by the Selling Securityholders, to the extent required, an accompanying prospectus supplement or, if appropriate, a post-effective amendment to the registration statement of which this prospectus is part, will be prepared and will set forth the following information:

•the specific securities to be offered and sold;

•the names of the selling securityholders;

•the respective purchase prices and public offering prices, the proceeds to be received from the sale, if any, and other material terms of the offering;

•settlement of short sales entered into after the date of this prospectus;

•the names of any participating agents, broker-dealers or underwriters, if not already named herein; and

•any applicable commissions, discounts, concessions and other items constituting compensation from the selling securityholders.

In connection with distributions of the securities or otherwise, the Selling Securityholders may enter into hedging transactions with broker-dealers or other financial institutions. In connection with such transactions, broker-

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dealers or other financial institutions may engage in short sales of the securities in the course of hedging the positions they assume with Selling Securityholders. The Selling Securityholders may also sell the securities short and redeliver the securities to close out such short positions. The Selling Securityholders may also enter into option or other transactions with broker-dealers or other financial institutions which require the delivery to such broker-dealer or other financial institution of securities offered by this prospectus, which securities such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction). The Selling Securityholders may also pledge securities to a broker-dealer or other financial institution, and, upon a default, such broker-dealer or other financial institution, may effect sales of the pledged securities pursuant to this prospectus (as supplemented or amended to reflect such transaction).

In order to facilitate the offering of the securities, any underwriters or agents, as the case may be, involved in the offering of such securities may engage in transactions that stabilize, maintain or otherwise affect the price of our securities. Specifically, the underwriters or agents, as the case may be, may overallot in connection with the offering, creating a short position in our securities for their own account. In addition, to cover overallotments or to stabilize the price of our securities, the underwriters or agents, as the case may be, may bid for, and purchase, such securities in the open market. Finally, in any offering of securities through a syndicate of underwriters, the underwriting syndicate may reclaim selling concessions allotted to an underwriter or a broker-dealer for distributing such securities in the offering if the syndicate repurchases previously distributed securities in transactions to cover syndicate short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of the securities above independent market levels. The underwriters or agents, as the case may be, are not required to engage in these activities, and may end any of these activities at any time.

The Selling Securityholders may solicit offers to purchase the securities directly from, and may sell such securities directly to, institutional investors or others. In this case, no underwriters or agents would be involved. The terms of any of those sales, including the terms of any bidding or auction process, if utilized, will be described in the applicable prospectus supplement.

It is possible that one or more underwriters may make a market in our securities, but such underwriters will not be obligated to do so and may discontinue any market making at any time without notice. We cannot give any assurance as to the liquidity of the trading market for our securities. Our shares of Class A common are currently listed on NYSE under the symbol "MPLN."

The Selling Securityholders may authorize underwriters, broker-dealers or agents to solicit offers by certain purchasers to purchase the securities at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. The contracts will be subject only to those conditions set forth in the prospectus supplement, and the prospectus supplement will set forth any commissions we or the Selling Securityholders pay for solicitation of these contracts.

A Selling Securityholder may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by any Selling Securityholder or borrowed from any Selling Securityholder or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from any Selling Securityholder in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter and will be identified in the applicable prospectus supplement (or a post-effective amendment). In addition, any Selling Securityholder may otherwise loan or pledge securities to a financial institution or other third party that in turn may sell the securities short using this prospectus. Such financial institution or other third party may transfer its economic short position to investors in our securities or in connection with a concurrent offering of other securities.

In effecting sales, broker-dealers or agents engaged by the Selling Securityholders may arrange for other broker-dealers to participate. Broker-dealers or agents may receive commissions, discounts or concessions from the Selling Securityholders in amounts to be negotiated immediately prior to the sale.

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In compliance with the guidelines of the Financial Industry Regulatory Authority ("FINRA"), the aggregate maximum discount, commission, fees or other items constituting underwriting compensation to be received by any FINRA member or independent broker-dealer will not exceed 8% of the gross proceeds of any offering pursuant to this prospectus and any applicable prospectus supplement.

If at the time of any offering made under this prospectus a member of FINRA participating in the offering has a "conflict of interest" as defined in FINRA Rule 5121 ("Rule 5121"), that offering will be conducted in accordance with the relevant provisions of Rule 5121.

To our knowledge, there are currently no plans, arrangements or understandings between the Selling Securityholders and any broker-dealer or agent regarding the sale of the securities by the Selling Securityholders. Upon our notification by a Selling Securityholder that any material arrangement has been entered into with an underwriter or broker-dealer for the sale of securities through a block trade, special offering, exchange distribution, secondary distribution or a purchase by an underwriter or broker-dealer, we will file, if required by applicable law or regulation, a supplement to this prospectus pursuant to Rule 424(b) under the Securities Act disclosing certain material information relating to such underwriter or broker-dealer and such offering.

Underwriters, broker-dealers or agents may facilitate the marketing of an offering online directly or through one of their affiliates. In those cases, prospective investors may view offering terms and a prospectus online and, depending upon the particular underwriter, broker-dealer or agent, place orders online or through their financial advisors.

In offering the securities covered by this prospectus, the Selling Securityholders and any underwriters, broker-dealers or agents who execute sales for the Selling Securityholders may be deemed to be "underwriters" within the meaning of the Securities Act in connection with such sales. Any discounts, commissions, concessions or profit they earn on any resale of those securities may be underwriting discounts and commissions under the Securities Act.

The underwriters, broker-dealers and agents may engage in transactions with us or the Selling Securityholders, may have banking, lending or other relationships with us or perform services for us or the Selling Securityholders, in the ordinary course of business.

In order to comply with the securities laws of certain states, if applicable, the securities must be sold in such jurisdictions only through registered or licensed brokers or dealers. In addition, in certain states the securities may not be sold unless they have been registered or qualified for sale in the applicable state or an exemption from the registration or qualification requirement is available and is complied with.

The Selling Securityholders and any other persons participating in the sale or distribution of the securities will be subject to applicable provisions of the Securities Act and the Exchange Act, and the rules and regulations thereunder, including, without limitation, Regulation M. These provisions may restrict certain activities of, and limit the timing of purchases and sales of any of the securities by, the Selling Securityholders or any other person, which limitations may affect the marketability of the shares of the securities.

We will make copies of this prospectus available to the Selling Securityholders for the purpose of satisfying the prospectus delivery requirements of the Securities Act. The Selling Securityholders may indemnify any agent, broker-dealer or underwriter that participates in transactions involving the sale of the securities against certain liabilities, including liabilities arising under the Securities Act.

We have agreed to indemnify the Selling Securityholders against certain liabilities, including certain liabilities under the Securities Act, the Exchange Act or other federal or state law. Agents, broker-dealers and underwriters may be entitled to indemnification by us and the Selling Securityholders against certain civil liabilities, including liabilities under the Securities Act, or to contribution with respect to payments which the agents, broker-dealers or underwriters may be required to make in respect thereof.

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LEGAL MATTERS

The validity of the issuance of the shares of Class A common stock offered hereby will be passed upon for MultiPlan Corporation by Simpson Thacher & Bartlett LLP, Palo Alto, California. Any underwriters will be advised about legal matters by their own counsel, which will be named in a prospectus supplement.

EXPERTS

The financial statements incorporated in this Prospectus by reference to the Annual Report on Form 10-K for the year ended December 31, 2020 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

In connection with the Transactions, PricewaterhouseCoopers LLP ("PwC") completed an independence assessment to evaluate the services and relationships with MultiPlan Parent and its affiliates that may bear on PwC's independence under the SEC and PCAOB independence rules for an audit period commencing January 1, 2017. PwC informed MultiPlan Parent that certain of its member firms within PricewaterhouseCoopers International Limited, each member firm of which is a separate legal entity (each, a "PwC member firm"), had performed non-audit services for and entered into a business relationship with certain entities that were affiliates of MultiPlan Parent. The performance of employee activities, deemed a management function pursuant to Rule 2-01(c)(4)(vi) of Regulation S-X under the SEC's auditor independence rules, and the existence of a prohibited business relationship in violation of Rule 2-01(c)(3) of Regulation S-X identified at certain controlled portfolio companies of investment funds controlled by Hellman & Friedman LLC and its affiliates, which currently are the majority equity holder of MultiPlan Parent's immediate parent company, are described below:

•Commencing in January 2017 and continuing through March 2019, a PwC member firm provided certain professional services related to a whistleblower program to an entity under common control with MultiPlan Parent. The fees for these services were less than $125,000.

•Commencing in January 2017 and continuing through March 2018, a PwC member firm provided certain shareholder resolution preparation services to an entity under common control with MultiPlan Parent. The fees for these services were approximately $170.

•Commencing in January 2019 and continuing through May 2019, a PwC member firm entered into a business relationship with an entity under common control with MultiPlan Parent to provide insurance advisory services to an unrelated third party client. The fees for these services were approximately $2,000.

PwC noted, among other things, the business relationship and non-audit services were entered into with sister entities under common control with MultiPlan Parent and the fees for projects involving the business relationship and relating to the non-audit services were immaterial to MultiPlan Parent, PwC, the respective PwC member firms, and the sister entities under common control with MultiPlan Parent.

After consideration of the relevant facts and circumstances, management and the Audit Committee of MultiPlan Parent's parent company concurred with PwC's conclusion that, for the reasons described above, the impermissible services and business relationship did not impair PwC's objectivity and impartiality with respect to the planning and execution of the audits of MultiPlan Parent's financial statements for each of the years ended December 31, 2020, 2019 and 2018 that are incorporated by reference herein and that no reasonable investor would conclude otherwise.

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WHERE YOU CAN FIND MORE INFORMATION

We have filed with the SEC a registration statement on Form S-3 under the Securities Act with respect to the shares of Class A common stock offered hereby. This prospectus does not contain all of the information set forth in the registration statement and the exhibits and schedules thereto. For further information with respect to the Company and its Class A common stock, reference is made to the registration statement and the exhibits and any schedules filed therewith. Statements contained in this prospectus as to the contents of any contract or other document referred to are not necessarily complete and in each instance, if such contract or document is filed as an exhibit, reference is made to the copy of such contract or other document filed as an exhibit to the registration statement, each statement being qualified in all respects by such reference. The SEC maintains a website at www.sec.gov, from which interested persons can electronically access the registration statement, including the exhibits and any schedules thereto and which contains the periodic reports, proxy and information statements and other information that we file electronically with the SEC.

We also maintain an Internet website at www.multiplan.us. Through our website, we make available, free of charge, the following documents of MultiPlan Corporation as soon as reasonably practicable after they are electronically filed with, or furnished to, the SEC: Annual Reports on Form 10-K; proxy statements for our annual and special shareholder meetings; Quarterly Reports on Form 10-Q; Current Reports on Form 8-K; Forms 3, 4 and 5 and Schedules 13D; and amendments to those documents. The information contained on, or that may be accessed through, our website is not part of, and is not incorporated into, this prospectus or the registration statement of which it forms a part.

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INCORPORATION BY REFERENCE

The rules of the SEC allow us to incorporate information into this prospectus by reference. This means that we are disclosing important information to you by referring to other documents. The information incorporated by reference is considered to be part of this prospectus, except for any information superseded by information contained directly in this prospectus. We incorporate by reference the documents listed below and all documents that we subsequently file with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of the offering of securities by means of this prospectus, from their respective filing dates (other than any portions thereof, which under the Exchange Act, and applicable SEC rules, are not deemed "filed" under the Exchange Act):

•our Annual Report on Form 10-K for the year ended December 31, 2020, filed with the SEC on March 16, 2021, as amended by our Annual Report on Form 10-K/A for the year ended December 31, 2020, filed with the SEC on March 24, 2021;

•our Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2021, filed with the SEC on May 13, 2021; our Quarterly Report on Form 10-Q for the quarterly period ended June 30, 2021, filed with the SEC on August 6, 2021; and our Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2021, filed with the SEC on November 4, 2021;

•our Current Reports on Form 8-K filed with the SEC on January 4, 2021, June 1, 2021, August 6, 2021, August 16, 2021, August 18, 2021, August 25, 2021, August 27, 2021 and November 16, 2021; and

•the description of our securities contained in the Registrant's Registration Statement on Form 8-A12B filed with the SEC on February 12, 2020.

The information incorporated by reference into this prospectus is an important part of this prospectus. Neither we nor any underwriters have authorized anyone to provide you with information other than that contained in or incorporated by reference into this prospectus. You should not assume that the information in this prospectus is accurate as of any date other than the date of this prospectus.

You should not rely on or assume the accuracy of any representation or warranty in any agreement that we have filed as an exhibit to any document that we have publicly filed or that we may otherwise publicly file in the future because such representation or warranty may be subject to exceptions and qualifications contained in separate disclosure schedules, may have been included in such agreement for the purpose of allocating risk between the parties to the particular transaction, and may no longer continue to be true as of any given date.

If we have incorporated by reference any statement or information in this prospectus and we subsequently modify that statement or information with information contained in this prospectus, the statement or information previously incorporated in this prospectus is also modified or superseded in the same manner.

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PART II. INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other expenses of issuance and distribution

The following table sets forth all costs and expenses, other than underwriting discounts and commissions, payable by us in connection with the Class A common stock being registered. All amounts shown are estimates except for the Securities and Exchange Commission (the "SEC") registration fee.

Amount paid or to be paid
SEC registration fee	$	52,783.38
Legal fees and expenses	100,000.00
Accounting fees and expenses	12,250.00
Miscellaneous	50,000.00
Total	$	215,033.38

Item 15. Indemnification of directors and officers

Section 102(b)(7) of the Delaware General Corporation Law (the "DGCL") allows a corporation to provide in its certificate of incorporation that a director of the corporation will not be personally liable to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except where the director breached the duty of loyalty, failed to act in good faith, engaged in intentional misconduct or knowingly violated a law, authorized the payment of a dividend or approved a stock repurchase in violation of Delaware corporate law or obtained an improper personal benefit. The Company's second amended and restated certificate of incorporation provides for this limitation of liability.

Section 145 of the DGCL, provides, among other things, that a Delaware corporation may indemnify any person who was, is or is threatened to be made, party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of such corporation), by reason of the fact that such person is or was an officer, director, employee or agent of such corporation or is or was serving at the request of such corporation as a director, officer, employee or agent of another corporation or enterprise. The indemnity may include expenses (including attorneys' fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by such person in connection with such action, suit or proceeding, provided such person acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the corporation's best interests and, with respect to any criminal action or proceeding, had no reasonable cause to believe that his or her conduct was unlawful. A Delaware corporation may indemnify any persons who were or are a party to any threatened, pending or completed action or suit by or in the right of the corporation by reason of the fact that such person is or was a director, officer, employee or agent of another corporation or enterprise. The indemnity may include expenses (including attorneys' fees) actually and reasonably incurred by such person in connection with the defense or settlement of such action or suit, provided such person acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the corporation's best interests, provided further that no indemnification is permitted without judicial approval if the officer, director, employee or agent is adjudged to be liable to the corporation. Where an officer or director is successful on the merits or otherwise in the defense of any action referred to above, the corporation must indemnify him or her against the expenses (including attorneys' fees) which such officer or director has actually and reasonably incurred.

Section 145 further authorizes a corporation to purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the corporation or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation or enterprise, against any liability asserted against such person and incurred by such person in any such capacity, or arising out of his or her status as such, whether or not the corporation would otherwise have the power to indemnify such person under Section 145.

The Company's amended and restated bylaws provide that we must indemnify and advance expenses to our directors and officers to the full extent authorized by the DGCL.

We have entered into indemnification agreements with each of our directors and executive officers. Such agreements may require us, among other things, to advance expenses and otherwise indemnify our executive officers

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and directors against certain liabilities that may arise by reason of their status or service as executive officers or directors, to the fullest extent permitted by law. We intend to enter into indemnification agreements with any new directors and executive officers in the future.

The indemnification rights set forth above shall not be exclusive of any other right which an indemnified person may have or hereafter acquire under any statute, any provision of the Company's second amended and restated certificate of incorporation, the Company's second amended and restated bylaws, agreement, vote of stockholders or disinterested directors or otherwise. Notwithstanding the foregoing, the Company shall not be obligated to indemnify a director or officer in respect of a proceeding (or part thereof) instituted by such director or officer, unless such proceeding (or part thereof) has been authorized by the Board pursuant to the applicable procedure outlined in the Company's second amended and restated bylaws.

Section 174 of the DGCL provides, among other things, that a director, who willfully or negligently approves of an unlawful payment of dividends or an unlawful stock purchase or redemption, may be held jointly and severally liable for such actions. A director who was either absent when the unlawful actions were approved or dissented at the time may avoid liability by causing his or her dissent to such actions to be entered in the books containing the minutes of the meetings of the board of directors at the time such action occurred or immediately after such absent director receives notice of the unlawful acts.

The Company maintains and expect to maintain standard policies of insurance that provide coverage (1) to its directors and officers against loss rising from claims made by reason of breach of duty or other wrongful act and (2) to the Company with respect to indemnification payments that the Company may make to such directors and officers.

These provisions may discourage stockholders from bringing a lawsuit against our directors for breach of their fiduciary duty. These provisions also may have the effect of reducing the likelihood of derivative litigation against directors and officers, even though such an action, if successful, might otherwise benefit the Company and our stockholders. Furthermore, a stockholder's investment may be adversely affected to the extent we pay the costs of settlement and damage awards against officers and directors pursuant to these indemnification provisions.

The Company believes that these provisions, the insurance and the indemnity agreements are necessary to attract and retain talented and experienced officers and directors.

Item 16. Exhibits

See the Exhibit Index immediately preceding the signature page for a list of exhibits filed as part of this registration statement, which Exhibit Index is incorporated herein by reference.

Item 17. Undertakings

The undersigned registrant, hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

i. To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

ii. To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement;

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iii. To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided, however, that paragraphs (1)(i), (ii) and (iii) above do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the registrant pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4) That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(A) each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(B) each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering being made pursuant to Rule 415(a)(1)(i), (vii) or (x) for the purpose of providing the information required by section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

(5) That, for the purpose of determining any liability under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

i. Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

ii. Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

iii. The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

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iv. Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

(6) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant's annual report pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(7) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the undersigned pursuant to the foregoing provisions, or otherwise, the undersigned has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the undersigned of expenses incurred or paid by a director, officer or controlling person of the undersigned in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the undersigned will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

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EXHIBIT INDEX

Incorporated by Reference
Exhibit Number	Description	Form	File No.	Exhibit	Filing Date	Filed Herewith
2.1	Agreement and Plan of Merger, dated as of July 12, 2020, by and among Churchill Capital Corp III, Music Merger Sub I, Inc., Music Merger Sub II, LLC, Polaris Parent Corp. and Polaris Investment Holdings, L.P.	8-K	001-39228	2.1	July 13, 2020
4.1	Specimen Class A common stock Certificate	8-K	001-39228	4.1	October 9, 2020
4.2	Specimen Warrant Certificate (included in Exhibit 4.3)
4.3	Warrant Agreement, dated February 13, 2020, between Continental Stock Transfer & Trust Company and Churchill Capital Corp III	8-K	001-39228	4.1	February 19, 2020
4.4	Specimen Warrant Certificate (included in Exhibit 4.5)
4.5	Warrant Agreement, dated October 8, 2020, between Continental Stock Transfer & Trust Company and Churchill Capital Corp III	8-K	001-39228	4.5	October 9, 2020
4.6	Indenture, dated as of October 8, 2020, by and between Churchill Capital Corp III and Wilmington Trust, National Association	8-K	001-39228	4.6	October 9, 2020
4.7	Form of 6.00% / 7.00% Convertible Senior PIK Toggle Notes due 2027 (included in Exhibit 4.6)
4.8	Indenture, dated as of November 21, 2017, between Polaris Intermediate Corp. and Wilmington Trust, National Association	8-K	001-39228	4.8	October 9, 2020
4.9	Form of 8.500% / 9.250% Senior PIK Toggle Notes due 2022 (included in Exhibit 4.8)
4.10	Indenture, dated as of June 7, 2016, between MPH Acquisition Corp. 1 (as successor to Polaris Merger Sub Corp.) and Wilmington Trust, National Association	8-K	001-39228	4.10	October 9, 2020
4.11	Form of 7.125% Senior Notes due 2024 (included in Exhibit 4.10)
4.12	First Supplemental Indenture, dated as of June 7, 2016, to that certain Indenture, dated as of June 7, 2016, between MPH Acquisition Holdings LLC (as successor to MPH Acquisition Corp. 1) and Wilmington Trust, National Association	8-K	001-39228	4.12	October 9, 2020
4.13	Second Supplemental Indenture, dated as of November 18, 2016, to that certain Indenture, dated as of June 7, 2016, between MPH Acquisition Holdings LLC and Wilmington Trust, National Association	8-K	001-39228	4.13	October 9, 2020

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Incorporated by Reference
Exhibit Number	Description	Form	File No.	Exhibit	Filing Date	Filed Herewith
4.14	Indenture, dated as of October 29, 2020, between MPH Acquisition Holdings LLC, the guarantors named therein and Wilmington Trust, National Association	8-K	001-39228	4.1	October 30, 2020
4.15	Form of 5.750% Senior Notes due 2028 (included in Exhibit 4.14)
4.16	Indenture, dated as of August 24, 2021, by and among MPH Acquisition Holdings LLC, the guarantors party thereto and Wilmington Trust, National Association	8-K	001-39228	4.1	August 25, 2021
4.17	Form of 5.50% Senior Secured Note due 2028 (included in Exhibit 4.16)
5.1	Opinion of Simpson Thacher & Bartlett LLP	S-3	333-260783	5.1	November 4, 2021
10.1	Investor Rights Agreement, dated as of July 12, 2020, by and among Churchill Capital Corp III, Polaris Investment Holdings, L.P., Churchill Sponsor III LLC, Hellman & Friedman Capital Partners VIII, L.P., The Public Investment Fund of The Kingdom of Saudi Arabia, and the other parties named therein	8-K	001-39228	10.1	July 13, 2020
10.2	Amended and Restated Sponsor Agreement, dated as of July 12, 2020, by and among Churchill Capital Corp III, Churchill Sponsor III LLC, and the other parties thereto	8-K	001-39228	10.5	July 13, 2020
10.3	Private Placement Warrants Purchase Agreement between Churchill Capital Corp III and Churchill Sponsor III LLC	S-1	333-236153	10.6	January 29, 2020
10.4	Common Subscription Agreement dated as of July 12, 2020, by and between Churchill Capital Corp III and The Public Investment Fund of The Kingdom of Saudi Arabia	8-K	001-39228	10.2	July 13, 2020
10.5	Form of Other Common Subscription Agreement	8-K	001-39228	10.3	July 13, 2020
10.6	Form of Convertible Subscription Agreement	8-K	001-39228	10.4	July 13, 2020
10.7	Promissory Note, dated as of July 12, 2020, by and between Churchill Capital Corp III and Churchill Sponsor III LLC	8-K	001-39228	10.6	July 13, 2020
10.8	Incremental Revolving Credit Commitment Increase Agreement No. 1, dated as of October 29, 2020, among MPH Acquisition Corp 1, MPH Acquisition Holdings LLC, as the Borrower, Barclays Bank PLC, as Administrative Agent, the Incremental Revolving Credit Commitment Increase Lenders party thereto and the other parties party thereto	8-K	001-39228	10.1	October 30, 2020

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Incorporated by Reference
Exhibit Number	Description	Form	File No.	Exhibit	Filing Date	Filed Herewith
10.9	Credit Agreement, dated as of August 24, 2021, by and among MPH Acquisition Corp. 1, MPH Acquisition Holdings LLC, the Co-Obligors from time to time party thereto, the Lenders and Letter of Credit Issuers from time to time party thereto and Goldman Sachs Lending Partners LLC, as the Administrative Agent, Collateral Agent, Swingline Lender and Letter of Credit Issuer	8-K	001-39228	10.1	August 25, 2021
10.10#	MultiPlan 2020 Omnibus Incentive Plan	S-8	333.251250	4.1	December 10, 2020
10.11#	Form of Director Restricted Stock Unit Award under the 2020 Omnibus Incentive Plan	10-K	001-39228	10.12	March 16, 2021
10.12#	Form of Employee Restricted Stock Unit Award under the 2020 Omnibus Incentive Plan	10-K	001-39228	10.13	March 16, 2021
10.13#	Form of Restricted Stock Award under the 2020 Omnibus Incentive Plan	10-K	001-39228	10.14	March 16, 2021
10.14#	Form of Option Award under the 2020 Omnibus Incentive Plan	10-K	001-39228	10.15	March 16, 2021
10.15#+	Amended and Restated Employment Agreement, dated May 5, 2016, by and among Mark Tabak, Polaris Investment Holdings, L.P. and MultiPlan, Inc.	8-K	001-39228	10.13	October 9, 2020
10.16#	Side Letter between Mark H. Tabak and MultiPlan, Inc., effective August 4, 2021, amending the Amended and Restated Employment Agreement by and between Mr. Tabak, MultiPlan, Inc. and Polaris Investment Holdings, L.P.	8-K	001-39228	10.1	August 6, 2021
10.17#+	Amended and Restated Employment Agreement, dated May 5, 2016, by and among David Redmond, Polaris Investment Holdings, L.P. and MultiPlan, Inc.	8-K	001-39228	10.14	October 9, 2020
10.18#	Side Letter between David L. Redmond and MultiPlan, Inc., effective August 4, 2021, amending the Amended and Restated Employment Agreement by and between Mr. Redmond, MultiPlan, Inc. and Polaris Investment Holdings, L.P.	8-K	001-39228	10.2	August 6, 2021
10.19#+	Amended and Restated Employment Agreement, dated May 5, 2016, by and among Dale White, Polaris Investment Holdings, L.P. and MultiPlan, Inc.	8-K	001-39228	10.15	October 9, 2020
10.20#	Offer Letter to Jeffrey Doctoroff, dated June 25, 2014	8-K	001-39228	10.16	October 9, 2020
10.21#	Form of Director and Officer Indemnification Agreement	8-K	001-39228	10.17	October 9, 2020
10.22#	Employment Agreement, dated November 15, 2021, by and between Multiplan Corporation and James Head	8-K	001-39228	10.1	November 16, 2021
23.1	Consent of Simpson Thacher & Bartlett LLP (included in Exhibit 5.1)

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Incorporated by Reference
Exhibit Number	Description	Form	File No.	Exhibit	Filing Date	Filed Herewith
23.2	Consent of PricewaterhouseCoopers LLP	X
24.1	Power of Attorney (included on the signature page)	S-3	333-260703	24.1	November 4, 2021

_________________

+ The schedules and exhibits to this agreement have been omitted pursuant to Item 601(b)(2) of Regulation S-K. A copy of any omitted schedule and/or exhibit will be furnished to the SEC upon request.

# Management contract or compensatory plan or arrangement.

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Signatures

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this registration statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of New York, State of New York, on the 8th day of December, 2021.

MultiPlan Corporation

By:

/s/ Jeffrey Doctoroff

Name: Jeffrey Doctoroff

Title: Senior Vice President, General Counsel and
Secretary

Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed by the following persons in the capacities and on the dates indicated.

Signature	Title	Date
*	Chief Executive Officer (Principal Executive Officer) and Chairperson of the Board of Directors	December 8, 2021
Mark H. Tabak
/s/ James M. Head	Executive Vice President and Chief Financial Officer (Principal Financial Officer)	December 8, 2021
James M. Head
*	Chief Accounting Officer (Principal Accounting Officer)	December 8, 2021
Gerald J. Kozel
*	Lead Independent Director	December 8, 2021
Allen R. Thorpe
*	Director	December 8, 2021
Glenn R. August
*	Director	December 8, 2021
Richard A. Clarke
*	Director	December 8, 2021
Anthony Colaluca, Jr.
*	Director	December 8, 2021
Paul D. Emery
*	Director	December 8, 2021
C. Martin Harris

*	Director	December 8, 2021
Julie D. Klapstein
*	Director	December 8, 2021
Michael S. Klein
*	Director	December 8, 2021
P. Hunter Philbrick
*	Director	December 8, 2021
William L. Veghte

*By:

/s/ Jeffrey Doctoroff

Jeffrey Doctoroff

As Attorney-in-fact