Blackrock Long-Horizon Equity Fund

05/17/2024 | Press release | Distributed by Public on 05/17/2024 04:01

Summary Prospectus by Investment Company - Form 497K

BlackRock Unconstrained Equity Fund - K Shares
MAY 14, 2024

Summary Prospectus

BlackRock Unconstrained Equity Fund | Class K Shares

Class K: MKEAX

Before you invest, you may want to review the Fund's prospectus, which contains more information about the Fund and its risks. You can find the Fund's prospectus (including amendments and supplements), reports to shareholders and other information about the Fund, including the Fund's statement of additional information, online at https://www.blackrock.com/prospectus. You can also get this information at no cost by calling (800) 537-4942 or by sending an e-mail request to [email protected], or from your financial professional. The Fund's prospectus and statement of additional information, both dated May 14, 2024, as amended and supplemented from time to time, are incorporated by reference into (legally made a part of) this Summary Prospectus.

This Summary Prospectus contains information you should know before investing, including information about risks. Please read it before you invest and keep it for future reference.

The Securities and Exchange Commission has not approved or disapproved these securities or passed upon the adequacy of this Summary Prospectus. Any representation to the contrary is a criminal offense.

Not FDIC Insured • May Lose Value • No Bank Guarantee

Summary Prospectus

Key Facts About BlackRock Unconstrained Equity Fund

Investment Objective

The investment objective of the BlackRock Unconstrained Equity Fund (the "Fund") is to seek to achieve long term capital growth.

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy, hold and sell Class K Shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to your financial professional or your selected securities dealer, broker, investment adviser, service provider or industry professional (including BlackRock Advisors, LLC ("BlackRock") and its affiliates) (each, a "Financial Intermediary"), which are not reflected in the table and example below.

Annual Fund Operating Expenses

(expenses that you pay each year as a percentage of the value of your investment)

Class K
Shares

Management Fee1

0.80%

Distribution and/or Service (12b-1) Fees

None

Other Expenses2

0.23%

Total Annual Fund Operating Expenses

1.03%

Fee Waivers and/or Expense Reimbursements1,3

(0.13)%

Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements1,3

0.90%
1

As described in the "Management of the Fund" section of the Fund's prospectus beginning on page 33, BlackRock has contractually agreed to waive the management fee with respect to any portion of the Fund's assets estimated to be attributable to investments in other equity and fixed-income mutual funds and exchange-traded funds managed by BlackRock or its affiliates that have a contractual management fee, through June 30, 2026. In addition, BlackRock has contractually agreed to waive its management fees by the amount of investment advisory fees the Fund pays to BlackRock indirectly through its investment in money market funds managed by BlackRock or its affiliates, through June 30, 2026. The contractual agreements may be terminated upon 90 days' notice by a majority of the non-interested trustees of the Trust or by a vote of a majority of the outstanding voting securities of the Fund.

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Other Expenses are based on estimated amounts for the Fund's current fiscal year.

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As described in the "Management of the Fund" section of the Fund's prospectus beginning on page 33, BlackRock has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses) as a percentage of average daily net assets to 0.90% for Class K Shares through June 30, 2026. The contractual agreement may be terminated upon 90 days' notice by a majority of the non-interested trustees of the Trust or by a vote of a majority of the outstanding voting securities of the Fund.

Example:

This Example is intended to help you compare the cost of investing in shares of the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in shares of the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

1 Year 3 Years 5 Years 10 Years

Class K Shares

$ 92 $ 301 $ 543 $ 1,235

Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 27% of the average value of its portfolio.

Principal Investment Strategies of the Fund

The Fund seeks to achieve its investment objective through a fully managed investment policy utilizing global equity securities. For purposes of the Fund's investment policies, equity securities include common stock, preferred stock,

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convertible securities, warrants, depositary receipts, and securities and other instruments whose price is linked to the value of common stock. The combination of equity securities will be varied from time to time both with respect to types of securities and markets in response to changing market and economic trends. Under normal circumstances, the Fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in equity and equity-related securities. This policy is a non-fundamental policy of the Fund and may not be changed without 60 days' prior notice to the Fund's shareholders.

The Fund seeks to achieve its investment objective by investing in equity securities of corporate issuers (which may include corporations, partnerships, trusts or other corporate-like entities) located around the world. The Fund has no geographic limits on where its investments may be located. This flexibility allows Fund management to look for investments in markets around the world that it believes will provide the best relative returns to meet the Fund's investment objective. The Fund may invest in the securities of companies of any market capitalization. The Fund may also invest in the securities of emerging growth companies.

The Fund is actively managed using an unconstrained investment style (i.e., it will not take a benchmark index into account when selecting the Fund's investments). Fund management, in its sole discretion, may invest in securities that are not included in the MSCI World Index. The Fund's portfolio holdings are expected to deviate materially from the MSCI World Index. The Fund may have exposure to a limited number of different investments, countries and/or sectors.

The Fund may use derivatives, including options, futures, swaps and forward contracts both to seek to increase the return of the Fund and to hedge (or protect) the value of its assets against adverse movements in currency exchange rates, interest rates and movements in the securities markets. In order to effectively manage cash flows into or out of the Fund, the Fund may buy and sell financial futures contracts or options on such contracts. Derivatives are financial instruments whose value is derived from another security, a commodity (such as oil or gas), a currency or an index.

The Fund may invest a portion of its assets in securities directly or indirectly secured by real estate or interests therein or issued by companies that invest in real estate or interests therein such as stock, bonds or convertible bonds issued by real estate investment trusts ("REITs").

The Fund may invest in both developed and emerging markets. In addition to investing in foreign securities, the Fund may manage its exposure to foreign currencies through the use of forward currency contracts and other currency derivatives. However, foreign exchange risk is not expected to be systematically hedged. From time to time, the Fund may own foreign cash equivalents or foreign bank deposits as part of the Fund's investment strategy. The Fund may also invest in non-U.S. currencies.

The Fund may invest in indexed and inverse securities.

To determine the Fund's investable universe, Fund management will first seek to screen out certain issuers based on certain environmental, social and governance ("ESG") criteria determined by BlackRock Advisors, LLC ("BlackRock"), subject to the considerations noted below. Such screening criteria principally includes: (i) issuers that derive more than zero percent of revenue from the production of controversial weapons; (ii) issuers that derive more than zero percent of revenue from the production of civilian firearms; (iii) issuers that derive more than zero percent of revenue from direct involvement in the production of nuclear weapons or nuclear weapon components or delivery platforms, or the provision of auxiliary services related to nuclear weapons; (iv) issuers that derive more than zero percent of revenue from the production of tobacco-related products; (v) issuers that derive more than five percent of revenue from tobacco-related activities; (vi) issuers that derive more than five percent of revenue from thermal coal generation, unless such issuers either (a) have made certain commitments to reduce climate impact or (b) derive at least fifty percent of revenue from alternative energy sources; (vii) issuers that derive more than five percent of revenue from thermal coal mining; (viii) issuers that derive more than five percent of revenue from oil sands extraction; (ix) issuers identified as violators of the United Nations Global Compact, which are globally accepted principles covering corporate behavior in the areas of human rights, labor, environment, and anti-corruption. Notwithstanding the foregoing, the Fund may invest in green bonds of issuers that exceed the thresholds stated in (vi), (vii) or (viii) above. The Fund relies on one or more third-party ratings agencies to identify issuers for purposes of the above screening criteria. Third-party rating agencies may base the above screening criteria on an estimate when revenue for a covered business activity is not disclosed by the issuer or publicly available.

The Fund's screening criteria is measured at the time of investment and is dependent upon information and data that may be incomplete, inaccurate, unavailable or estimated. Where the Fund's criteria looks solely to third-party ratings or data, issuers are only screened to the extent such ratings or data have been assigned or made available by the third parties. This screening criteria is subject to change over time at BlackRock's discretion.

The Fund may gain indirect exposure (through, including but not limited to, derivatives and investments in other investment companies) to issuers with exposures that are inconsistent with the ESG-related criteria used by Fund management.

The Fund is classified as non-diversified under the Investment Company Act of 1940, as amended (the "Investment Company Act"), which means that it can invest more of its assets in fewer issuers than a diversified company.

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Principal Risks of Investing in the Fund

Risk is inherent in all investing. The value of your investment in the Fund, as well as the amount of return you receive on your investment, may fluctuate significantly from day to day and over time. You may lose part or all of your investment in the Fund or your investment may not perform as well as other similar investments. The following is a summary description of the principal risks of investing in the Fund. The relative significance of each risk factor below may change over time and you should review each risk factor carefully.

Equity Securities Risk - Stock markets are volatile. The price of equity securities fluctuates based on changes in a company's financial condition and overall market and economic conditions.

Focus Risk - Under normal circumstances, the Fund focuses its investments in the securities of a limited number of issuers. This may subject the Fund to greater issuer-specific risk and potential losses than a fund that invests in the securities of a greater number of issuers.

Non-Diversification Risk - The Fund is a non-diversified fund. Because the Fund may invest in securities of a smaller number of issuers, it may be more exposed to the risks associated with and developments affecting an individual issuer than a fund that invests more widely.

Market Risk and Selection Risk - Market risk is the risk that one or more markets in which the Fund invests will go down in value, including the possibility that the markets will go down sharply and unpredictably. The value of a security or other asset may decline due to changes in general market conditions, economic trends or events that are not specifically related to the issuer of the security or other asset, or factors that affect a particular issuer or issuers, exchange, country, group of countries, region, market, industry, group of industries, sector or asset class. Local, regional or global events such as war, acts of terrorism, the spread of infectious illness or other public health issues like pandemics or epidemics, recessions, or other events could have a significant impact on the Fund and its investments. Selection risk is the risk that the securities selected by Fund management will underperform the markets, the relevant indices or the securities selected by other funds with similar investment objectives and investment strategies. This means you may lose money.

An outbreak of an infectious coronavirus (COVID-19) that was first detected in December 2019 developed into a global pandemic that has resulted in numerous disruptions in the market and has had significant economic impact leaving general concern and uncertainty. Although vaccines have been developed and approved for use by various governments, the duration of the pandemic and its effects cannot be predicted with certainty. The impact of this coronavirus, and other epidemics and pandemics that may arise in the future, could affect the economies of many nations, individual companies and the market in general ways that cannot necessarily be foreseen at the present time.

Geographic Concentration Risk -From time to time the Fund may invest a substantial amount of its assets in issuers located in a single country or a limited number of countries. If the Fund concentrates its investments in this manner, it assumes the risk that economic, political and social conditions in those countries will have a significant impact on its investment performance. The Fund's investment performance may also be more volatile if it concentrates its investments in certain countries, especially emerging market countries.

Foreign Securities Risk -Foreign investments often involve special risks not present in U.S. investments that can increase the chances that the Fund will lose money. These risks include:

The Fund generally holds its foreign securities and cash in foreign banks and securities depositories, which may be recently organized or new to the foreign custody business and may be subject to only limited or no regulatory oversight.

Changes in foreign currency exchange rates can affect the value of the Fund's portfolio.

The economies of certain foreign markets may not compare favorably with the economy of the United States with respect to such issues as growth of gross national product, reinvestment of capital, resources and balance of payments position.

The governments of certain countries, or the U.S. Government with respect to certain countries, may prohibit or impose substantial restrictions through capital controls and/or sanctions on foreign investments in the capital markets or certain industries in those countries, which may prohibit or restrict the ability to own or transfer currency, securities, derivatives or other assets.

Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to the same extent as does the United States and may not have laws to protect investors that are comparable to U.S. securities laws.

Settlement and clearance procedures in certain foreign markets may result in delays in payment for or delivery of securities not typically associated with settlement and clearance of U.S. investments.

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The Fund's claims to recover foreign withholding taxes may not be successful, and if the likelihood of recovery of foreign withholding taxes materially decreases, due to, for example, a change in tax regulation or approach in the foreign country, accruals in the Fund's net asset value for such refunds may be written down partially or in full, which will adversely affect the Fund's net asset value.

The European financial markets have recently experienced volatility and adverse trends due to concerns about economic downturns in, or rising government debt levels of, several European countries as well as acts of war in the region. These events may spread to other countries in Europe and may affect the value and liquidity of certain of the Fund's investments.

ESG Screening Risk -The Fund intends to screen out particular issuers pursuant to certain criteria established by BlackRock. The Fund may forgo certain investment opportunities by screening out such issuers, and the Fund's results may be lower than other funds that do not apply exclusionary screens or use different ESG-related screening criteria. Further, investors may differ in their views of what constitutes positive or negative ESG characteristics of an issuer. As a result, the Fund may invest in issuers that do not reflect the beliefs of any particular investor. In evaluating an issuer based on ESG criteria, BlackRock is dependent upon certain information and data from third party providers of ESG research, which may be incomplete, inaccurate or unavailable. As a result, there is a risk that BlackRock may incorrectly assess an issuer. There is also a risk that BlackRock may not apply the relevant ESG criteria correctly or that a Fund could have indirect exposure to issuers who do not meet the relevant ESG criteria used by such Fund. Neither the Fund nor BlackRock make any representation or warranty, express or implied, with respect to the fairness, correctness, accuracy, reasonableness or completeness of such ESG criteria.

Convertible Securities Risk -The market value of a convertible security performs like that of a regular debt security; that is, if market interest rates rise, the value of a convertible security usually falls. In addition, convertible securities are subject to the risk that the issuer will not be able to pay interest, principal or dividends when due, and their market value may change based on changes in the issuer's credit rating or the market's perception of the issuer's creditworthiness. Since it derives a portion of its value from the common stock into which it may be converted, a convertible security is also subject to the same types of market and issuer risks that apply to the underlying common stock, including the potential for increased volatility in the price of the convertible security.

Depositary Receipts Risk -Depositary receipts are generally subject to the same risks as the foreign securities that they evidence or into which they may be converted. In addition to investment risks associated with the underlying issuer, depositary receipts expose the Fund to additional risks associated with the non-uniform terms that apply to depositary receipt programs, credit exposure to the depository bank and to the sponsors and other parties with whom the depository bank establishes the programs, currency risk and the risk of an illiquid market for depositary receipts. The issuers of unsponsored depositary receipts are not obligated to disclose information that is, in the United States, considered material. Therefore, there may be less information available regarding these issuers and there may not be a correlation between such information and the market value of the depositary receipts. While depositary receipts provide an alternative to directly purchasing underlying foreign securities in their respective markets and currencies, they continue to be subject to many of the risks associated with investing directly in foreign securities, including political, economic, and currency risk.

Derivatives Risk -The Fund's use of derivatives may increase its costs, reduce the Fund's returns and/or increase volatility. Derivatives involve significant risks, including:

Leverage Risk - The Fund's use of derivatives can magnify the Fund's gains and losses. Relatively small market movements may result in large changes in the value of a derivatives position and can result in losses that greatly exceed the amount originally invested.
Market Risk - Some derivatives are more sensitive to interest rate changes and market price fluctuations than other securities. The Fund could also suffer losses related to its derivatives positions as a result of unanticipated market movements, which losses are potentially unlimited. Finally, BlackRock may not be able to predict correctly the direction of securities prices, interest rates and other economic factors, which could cause the Fund's derivatives positions to lose value.
Counterparty Risk - Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will be unable or unwilling to fulfill its contractual obligation, and the related risks of having concentrated exposure to such a counterparty.
Illiquidity Risk - The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately.
Operational Risk - The use of derivatives includes the risk of potential operational issues, including documentation issues, settlement issues, systems failures, inadequate controls and human error.
Legal Risk - The risk of insufficient documentation, insufficient capacity or authority of counterparty, or legality or enforceability of a contract.

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Volatility and Correlation Risk - Volatility is defined as the characteristic of a security, an index or a market to fluctuate significantly in price within a short time period. A risk of the Fund's use of derivatives is that the fluctuations in their values may not correlate with the overall securities markets.
Valuation Risk - Valuation for derivatives may not be readily available in the market. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them.
Hedging Risk - Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Fund's hedging transactions will be effective. The use of hedging may result in certain adverse tax consequences.
Tax Risk - Certain aspects of the tax treatment of derivative instruments, including swap agreements and commodity-linked derivative instruments, are currently unclear and may be affected by changes in legislation, regulations or other legally binding authority. Such treatment may be less favorable than that given to a direct investment in an underlying asset and may adversely affect the timing, character and amount of income the Fund realizes from its investments.

Emerging Markets Risk -Emerging markets are riskier than more developed markets because they tend to develop unevenly and may never fully develop. Investments in emerging markets may be considered speculative. Emerging markets are more likely to experience hyperinflation and currency devaluations, which adversely affect returns to U.S. investors. In addition, many emerging securities markets have far lower trading volumes and less liquidity than developed markets.

Indexed and Inverse Securities Risk -Indexed and inverse securities provide a potential return based on a particular index of value or interest rates. The Fund's return on these securities will be subject to risk with respect to the value of the particular index. These securities are subject to leverage risk and correlation risk. Certain indexed and inverse securities have greater sensitivity to changes in interest rates or index levels than other securities, and the Fund's investment in such instruments may decline significantly in value if interest rates or index levels move in a way Fund management does not anticipate.

Leverage Risk -Some transactions may give rise to a form of economic leverage. These transactions may include, among others, derivatives, and may expose the Fund to greater risk and increase its costs. The use of leverage may cause the Fund to liquidate portfolio positions when it may not be advantageous to do so to satisfy its obligations or to meet the applicable requirements of the Investment Company Act of 1940, as amended, and the rules thereunder. Increases and decreases in the value of the Fund's portfolio will be magnified when the Fund uses leverage.

Mid Cap Securities Risk -The securities of mid cap companies generally trade in lower volumes and are generally subject to greater and less predictable price changes than the securities of larger capitalization companies.

Preferred Securities Risk -Preferred securities may pay fixed or adjustable rates of return. Preferred securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company's preferred securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company's financial condition or prospects. Preferred securities of smaller companies may be more vulnerable to adverse developments than preferred securities of larger companies.

Real Estate-Related Securities Risk -The main risk of real estate-related securities is that the value of the underlying real estate may go down. Many factors may affect real estate values. These factors include both the general and local economies, vacancy rates, tenant bankruptcies, the ability to re-lease space under expiring leases on attractive terms, the amount of new construction in a particular area, the laws and regulations (including zoning, environmental and tax laws) affecting real estate and the costs of owning, maintaining and improving real estate. The availability of mortgage financing and changes in interest rates may also affect real estate values. If the Fund's real estate-related investments are concentrated in one geographic area or in one property type, the Fund will be particularly subject to the risks associated with that area or property type. Many issuers of real estate-related securities are highly leveraged, which increases the risk to holders of such securities. The value of the securities the Fund buys will not necessarily track the value of the underlying investments of the issuers of such securities. In addition, certain issuers of real estate-related securities may have developed or commenced development on properties and may develop additional properties in the future. Real estate development involves significant risks in addition to those involved in the ownership and operation of established properties. Real estate securities may have limited diversification and are, therefore, subject to risks inherent in operating and financing a limited number of projects. Real estate securities are also subject to heavy cash flow dependency and defaults by borrowers or tenants.

REIT Investment Risk -Investments in REITs involve unique risks. REITs may have limited financial resources, may trade less frequently and in limited volume, may engage in dilutive offerings of securities and may be more

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volatile than other securities. REIT issuers may also fail to maintain their exemptions from investment company registration or fail to qualify for the "dividends paid deduction" under the Internal Revenue Code of 1986, as amended (the "Internal Revenue Code"), which allows REITs to reduce their corporate taxable income for dividends paid to their shareholders.

Small Cap and Emerging Growth Securities Risk -Small cap or emerging growth companies may have limited product lines or markets. They may be less financially secure than larger, more established companies. They may depend on a more limited management group than larger capitalized companies.

Warrants Risk -If the price of the underlying stock does not rise above the exercise price before the warrant expires, the warrant generally expires without any value and the Fund will lose any amount it paid for the warrant. Thus, investments in warrants may involve substantially more risk than investments in common stock. Warrants may trade in the same markets as their underlying stock; however, the price of the warrant does not necessarily move with the price of the underlying stock.

Performance Information

The information shows you how the Fund's performance has varied year by year and provides some indication of the risks of investing in the Fund. Class K Shares do not have a performance history as of the date of this prospectus. As a result, the chart and the table give you a picture of the long-term performance for Institutional Shares of the Fund, which are not offered in this prospectus. The performance of Class K Shares would be substantially similar to Institutional Shares because Class K Shares and Institutional Shares are invested in the same portfolio of securities and performance would differ only to the extent that Institutional Shares and Class K Shares have different expenses. The actual returns of Class K Shares would have been higher than those of the Institutional Shares because Class K Shares have lower expenses than the Institutional Shares. Effective March 1, 2022, the Fund changed its name, investment objective, investment process and investment strategies. Performance shown below from October 15, 2012 to March 1, 2022 is based on the investment process and investment strategies utilized by the Fund prior to March 1, 2022 under the name "BlackRock Long-Horizon Equity Fund." The table compares the Fund's performance to that of the MSCI World Index. To the extent that dividends and distributions have been paid by the Fund, the performance information for the Fund in the chart and table assumes reinvestment of the dividends and distributions. As with all such investments, past performance (before and after taxes) is not an indication of future results. The table includes all applicable fees. If BlackRock and its affiliates had not waived or reimbursed certain Fund expenses during these periods, the Fund's returns would have been lower. Updated information on the Fund's performance, including its current net asset value, can be obtained by visiting http://www.blackrock.com or can be obtained by phone at (800) 882-0052.

Institutional Shares

ANNUAL TOTAL RETURNS

BlackRock Unconstrained Equity Fund

As of 12/31

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During the ten-year period shown in the bar chart, the highest return for a quarter was 17.81% (quarter ended June 30, 2020) and the lowest return for a quarter was -19.66% (quarter ended March 31, 2020).

For the periods ended 12/31/23

Average Annual Total Returns

1 Year 5 Years 10 Years

BlackRock Unconstrained Equity Fund - Institutional Shares

Return Before Taxes

33.37 % 15.71 % 9.21 %

Return After Taxes on Distributions

33.37 % 12.37 % 6.69 %

Return After Taxes on Distributions and Sale of Fund Shares

19.75 % 11.91 % 6.76 %

MSCI World Index
(Reflects no deduction for fees, expenses or taxes)

23.79 % 12.80 % 8.60 %

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and the after-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

Investment Manager

The Fund's investment manager is BlackRock Advisors, LLC (previously defined as "BlackRock"). The Fund's sub-adviser is BlackRock International Limited. Where applicable, the use of the term BlackRock also refers to the Fund's sub-adviser.

Portfolio Managers

Name

Portfolio Manager of the Fund Since Title

Alister Hibbert

2022 Managing Director of BlackRock, Inc.

Michael Constantis, CFA

2022 Managing Director of BlackRock, Inc.

Purchase and Sale of Fund Shares

Class K Shares of the Fund are available only to (i) certain employee benefit plans, such as health savings accounts, and certain employer-sponsored retirement plans (not including SEP IRAs, SIMPLE IRAs and SARSEPs) (collectively, "Employer-Sponsored Retirement Plans"), (ii) collective trust funds, investment companies and other pooled investment vehicles, each of which may purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Fund's distributor to purchase such shares, (iii) "Institutional Investors," which include, but are not limited to, endowments, foundations, family offices, banks and bank trusts, local, city, and state governmental institutions, corporations and insurance company separate accounts, each of which may purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Fund's distributor to purchase such shares, (iv) clients of private banks that purchase shares of the Fund through a Financial Intermediary that has entered into an agreement with the Fund's distributor to sell such shares; (v) fee-based advisory platforms of a Financial Intermediary that (a) has specifically acknowledged in a written agreement with the Fund's distributor and/or its affiliate(s) that the Financial Intermediary shall offer such shares to fee-based advisory clients through an omnibus account held at the Fund or (b) transacts in the Fund's shares through another intermediary that has executed such an agreement and (vi) any other investors who met the eligibility criteria for BlackRock Shares or Class K Shares prior to August 15, 2016 and have continually held Class K Shares of the Fund in the same account since August 15, 2016.

You may purchase or redeem shares of the Fund each day the New York Stock Exchange is open. Purchase orders may also be placed by calling (800) 537-4942, by mail (c/o BlackRock, P.O. Box 534429, Pittsburgh, Pennsylvania 15253-4429), or online at www.blackrock.com. Institutional Investors are subject to a $5 million minimum initial investment requirement. Other investors, including Employer-Sponsored Retirement Plans, have no minimum initial investment requirement. There is no minimum investment amount for additional purchases.

Tax Information

Different income tax rules apply depending on whether you are invested through a qualified tax-exempt plan described in section 401(a) of the Internal Revenue Code of 1986, as amended. If you are invested through such a plan (and Fund shares are not "debt-financed property" to the plan), then the dividends paid by the Fund and the gain realized from a redemption or exchange of Fund shares will generally not be subject to U.S. federal income taxes until you withdraw or receive distributions from the plan. If you are not invested through such a plan, then the Fund's dividends

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and gain from a redemption or exchange may be subject to U.S. federal income taxes and may be taxed as ordinary income or capital gains, unless you are a tax-exempt investor.

Payments to Broker/Dealers and Other Financial Intermediaries

If you purchase shares of the Fund through a Financial Intermediary, the Fund and BlackRock Investments, LLC, the Fund's distributor, or its affiliates may pay the Financial Intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the Financial Intermediary and your individual financial professional to recommend the Fund over another investment.

Class K Shares are only available through a Financial Intermediary if the Financial Intermediary will not receive from Fund assets, or the Fund's distributor's or an affiliate's resources, any commission payments, shareholder servicing fees (including sub-transfer agent and networking fees), or distribution fees (including Rule 12b-1 fees) with respect to assets invested in Class K Shares.

Ask your individual financial professional or visit your Financial Intermediary's website for more information.

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INVESTMENT COMPANY ACT FILE # 811-21759

SPRO-UNEQ-K-0524