Post-Effective Amendment to Registration Statement - Form POS AMI

DIVERSIFIED EQUITY MASTER PORTFOLIO

As Filed With the Securities and Exchange Commission on April 29, 2024

REGISTRATION NO. 811-08162

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM N-1A

REGISTRATION STATEMENT

UNDER

THE INVESTMENT COMPANY ACT OF 1940

AMENDMENT NO. 142

MASTER INVESTMENT PORTFOLIO

(EXACT NAME OF REGISTRANT AS SPECIFIED IN CHARTER)

400 HOWARD STREET

SAN FRANCISCO, CA 94105

(ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)

REGISTRANT'S TELEPHONE NUMBER: (800) 441-7762

JOHN M. PERLOWSKI

MASTER INVESTMENT PORTFOLIO

50 HUDSON YARDS

NEW YORK, NEW YORK 10001

UNITED STATES OF AMERICA

(NAME AND ADDRESS OF AGENT FOR SERVICE)

WITH A COPY TO:

JESSE C. KEAN, ESQ.		JANEY AHN, ESQ.
SIDLEY AUSTIN LLP		BLACKROCK FUND ADVISORS
787 SEVENTH AVENUE		50 HUDSON YARDS
NEW YORK, NEW YORK 10019		NEW YORK, NEW YORK 10001

MASTER INVESTMENT PORTFOLIO

DIVERSIFIED EQUITY MASTER PORTFOLIO

EXPLANATORY NOTE

This is the combined Part A and Part B of the Registration Statement on Form N-1A for Diversified Equity Master Portfolio (the "Master Portfolio"). The Master Portfolio is a diversified portfolio of Master Investment Portfolio ("MIP"), an open-end, series management investment company.

The Master Portfolio operates as part of a master/feeder structure, and one or more corresponding feeder funds invest all of its/their assets in a Master Portfolio with substantially the same investment objective, strategies and policies as the corresponding feeder fund. Throughout this combined Part A and Part B for the Master Portfolio, specified information concerning the Master Portfolio and MIP is incorporated by reference from the most recently effective post-effective amendment to the registration statement on Form N-1A under the Investment Company Act of 1940, as amended (the "1940 Act"), of BlackRock Funds III (File Nos. 33-54126; 811-07332) (the "Trust") that relates to and includes the prospectus and the statement of additional information of BlackRock Diversified Equity Fund (the "BlackRock Funds III Feeder Fund" or the "Feeder Fund"), a series of BlackRock Funds III and a separate publicly offered investment company organized as a Delaware statutory trust. To the extent that information concerning the Master Portfolio and/or MIP is incorporated by reference and the Trust has filed, pursuant to Rule 497 under the Securities Act of 1933, as amended (the "1933 Act"), a supplement to the BlackRock Funds III Feeder Fund's prospectus or statement of additional information that supplements such incorporated information, then the supplemented information contained in such Rule 497 filing is also incorporated herein by reference. The BlackRock Funds III Feeder Fund's current prospectus and statement of additional information, as supplemented from time to time, are referred to herein as the "Prospectus" and "SAI," respectively. From time to time, the Master Portfolio may have one or more feeder funds that are not BlackRock Funds III Feeder Funds. In addition, the Master Portfolio is a fund in which other funds may invest a portion of their assets pursuant to a fund of funds structure.

PART A - PROSPECTUS

April 29, 2024

THIS PART A DOES NOT CONSTITUTE AN OFFER TO SELL, OR THE SOLICITATION OF AN OFFER TO BUY, ANY "SECURITY" WITHIN THE MEANING OF THE SECURITIES ACT OF 1933, AS AMENDED (THE "1933 ACT").

The Master Portfolio's Part B, dated April 29, 2024, is incorporated by reference into this Part A.

ITEMS 1 THROUGH 4.

Responses to Items 1 through 4 have been omitted pursuant to General Instruction B, Paragraph 2(b), to Form N-1A under the Investment Company Act of 1940, as amended (the "1940 Act").

ITEM 5.

MANAGEMENT.

BlackRock Fund Advisors ("BFA" or the "Investment Adviser") is the investment adviser of the Master Portfolio.

The portfolio managers primarily responsible for the day-to-day management of the Master Portfolio are:

Portfolio Manager		Portfolio Manager of the Master Portfolio Since		Title
Philip Green		2016		Managing Director of BlackRock, Inc.
Michael Pensky		2024		Managing Director of BlackRock, Inc.
Daniel Felder		2024		Director of BlackRock, Inc.

ITEM 6.

PURCHASE AND SALE OF INTERESTS.

Interests in the Master Portfolio are issued solely in private placement transactions that do not involve any "public offering" within the meaning of Section 4(a)(2) of the 1933 Act. Investments in the Master Portfolio may only be made by investment companies or certain other entities that are "accredited investors" within the meaning of Regulation D under the 1933 Act.

The Master Portfolio has no minimum initial or subsequent investment requirements.

Each feeder fund may withdraw all or any portion of its investment in the Master Portfolio on any business day on which the New York Stock Exchange ("NYSE") is open at the net asset value ("NAV") next determined after a redemption request is received in proper form by the Master Portfolio.

ITEM 7.

TAX INFORMATION.

The Master Portfolio has more than one feeder fund and intends to operate as a non-publicly traded partnership for U.S. federal income tax purposes. If the Master Portfolio had only one feeder fund (either (i) directly or (ii) indirectly through an entity that is disregarded for U.S. federal income tax purposes), then the Master Portfolio's existence as an entity separate from that feeder fund would be disregarded for U.S. federal income tax purposes. Whether the Master Portfolio is a partnership or disregarded as a separate entity it will generally not be subject to U.S. federal income tax.

ITEM 8.

FINANCIAL INTERMEDIARY COMPENSATION.

Not applicable.

ITEM 9.

INVESTMENT OBJECTIVE, PRINCIPAL INVESTMENT STRATEGIES, RELATED RISKS AND DISCLOSURE OF PORTFOLIO HOLDINGS.

INVESTMENT OBJECTIVE

The investment objective of the Master Portfolio is to seek to provide long-term appreciation of capital.

The Master Portfolio's investment objective is non-fundamental, which means it can be changed by MIP's board of trustees (the "Board of Trustees" or the "Board") without approval by the holders of beneficial interests of the Master Portfolio (each, an "interestholder"). However, should the Board determine that the investment objective of the Master Portfolio should be changed, interestholders will be given at least 30 days' notice before any such change is made.

The investment objective and principal investment strategies of the Master Portfolio determine the securities in which it invests, the degree of risk to which it is subject and, ultimately, its performance. There can be no assurance that the investment objective of the Master Portfolio will be achieved.

INVESTMENT PROCESS

BFA engages in a variety of different activities and methods of analysis when choosing investments for the Master Portfolio, such as:

•

Reviewing and allocating varying percentages of the Master Portfolio to equity investment management team members responsible for security selection utilizing various investment styles and disciplines, including, but not limited to, stocks of large and small capitalization companies;

•

Utilizing a combination of quantitative and fundamental analysis (a method of stock market analysis that concentrates on "fundamental" information about the company (such as its income statement, balance sheet, earnings and sales history, products and management) to attempt to forecast future stock value) to evaluate the relative attractiveness of various segments in the equity universe, defined by style, capitalization range and geographic location; and

•

Identifying macroeconomic insights that BFA believes have the potential to outperform investments in the market as a whole. These themes may reflect changes in the global macroeconomic and policy backdrop.

To a limited extent, BFA may, when choosing investments for the Master Portfolio, engage in fundamental analysis and bottom-up security selection that, in turn, drive sector and industry weightings as well as average market capitalization. BFA may assess each stock's changing characteristics relative to its contribution to portfolio risk within that discipline and selling the stock when it no longer offers an appropriate return-to-risk trade-off.

The Master Portfolio may engage in active and frequent trading of portfolio securities to achieve its primary investment strategies.

PRINCIPAL INVESTMENT STRATEGIES

The Master Portfolio invests, under normal circumstances, at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in equity securities, including common stock, preferred stock, securities convertible into common stock and securities or other instruments whose price is linked to the value of common stock.

The Master Portfolio will provide interestholders with at least 60 days' notice of any change to the Master Portfolio's non-fundamental policy to invest at least 80% of the value of the Master Portfolio's net assets, plus the amount of any borrowings for investment purposes, in equity securities, including common stock, preferred stock, securities convertible into common stock and securities or other instruments whose price is linked to the value of common stock.

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The Master Portfolio does not limit its investments to companies of any particular size, and may invest in equity securities of companies of any market capitalization.

Equity securities include securities representing shares of ownership of a corporation ("common stock"), preferred stock, securities convertible into common stock and securities or other instruments whose price is linked to the value of common stock. Preferred stock is a class of stock that often pays dividends at a specified rate and has preference over common stock in dividend payments and liquidation of assets. Convertible securities typically pay current income as either interest (debt security convertibles) or dividends (preferred stock), and their value usually reflects both the stream of current income payments and the market value of the underlying common stock.

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The Master Portfolio may also invest in securities of foreign issuers from any country, including emerging market countries, and may invest in securities denominated in both U.S. dollars and non-U.S. dollar currencies.

The Master Portfolio may use derivatives to hedge its portfolio against market and currency risks or to gain exposure to equity markets. The Master Portfolio may also use derivatives to hedge its investment portfolio against interest rate risks or to seek to enhance its return. Derivatives are financial instruments whose value is derived from another security, a commodity (such as oil or gold), a currency or an index such as the Russell^® 1000 Index. The derivatives that the Master Portfolio may use include options on portfolio positions or currencies, financial and currency futures, options on such futures, forward foreign currency transactions and swaps.

The Master Portfolio may also invest in indexed and inverse securities.

OTHER STRATEGIES APPLICABLE TO THE MASTER PORTFOLIO

In addition to the principal strategies discussed above, the Master Portfolio may also invest or engage in the following investments/strategies:

BORROWING. The Master Portfolio may borrow for temporary or emergency purposes, including to meet redemptions, for the payment of dividends, for share repurchases or for the clearance of transactions, subject to the limits set forth under the 1940 Act, the rules and regulations thereunder and any applicable exemptive relief.

DEBT SECURITIES. Debt securities include fixed income securities issued by companies, as well as U.S. and foreign sovereign debt obligations. When choosing debt securities, BFA considers various factors including the credit quality of issuers and yield analysis.

DEPOSITARY RECEIPTS.The Master Portfolio may invest in securities of foreign issuers in the form of depositary receipts or other securities that are convertible into securities of foreign issuers. American Depositary Receipts are receipts typically issued by an American bank or trust company that evidence underlying securities issued by a foreign corporation. European Depositary Receipts (issued in Europe) and Global Depositary Receipts (issued throughout the world) each evidence a similar ownership arrangement. The Master Portfolio may invest in unsponsored depositary receipts.

ILLIQUID INVESTMENTS.The Master Portfolio may invest up to an aggregate amount of 15% of its net assets in illiquid investments. An illiquid investment is any investment that the Master Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment.

INITIAL PUBLIC OFFERINGS.The Master Portfolio has the ability to invest in initial public offerings ("IPOs").

INVESTMENT COMPANIES. The Master Portfolio has the ability to invest in other investment companies, such as exchange-traded funds ("ETFs"), unit investment trusts, and open-end and closed-end funds, subject to the applicable limits under the 1940 Act and the rules thereunder. The Master Portfolio may invest in affiliated investment companies, including affiliated money market funds and affiliated ETFs.

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MASTER LIMITED PARTNERSHIPS. The Master Portfolio may invest in publicly traded master limited partnerships ("MLPs"), which are limited partnerships or limited liability companies taxable as partnerships. MLPs generally have two classes of owners, the general partner and limited partners. If investing in an MLP, the Master Portfolio intends to purchase publicly traded common units issued to limited partners of the MLP. Limited partners have a limited role in the operations and management of the MLP.

REAL ESTATE INVESTMENT TRUSTS. The Master Portfolio may invest in real estate investment trusts ("REITs").

REPURCHASE AGREEMENTS AND PURCHASE AND SALE CONTRACTS. The Master Portfolio may enter into certain types of repurchase agreements or purchase and sale contracts. Under a repurchase agreement, the seller agrees to repurchase a security at a mutually agreed-upon time and price. A purchase and sale contract is similar to a repurchase agreement, but purchase and sale contracts also provide that the purchaser receives any interest on the security paid during the period.

RESTRICTED SECURITIES. Restricted securities are securities that cannot be offered for public resale unless registered under the applicable securities laws or that have a contractual restriction that prohibits or limits their resale. They may include Rule 144A securities, which are privately placed securities that can be resold to qualified institutional buyers but not to the general public, and securities of U.S. and non-U.S. issuers that are offered pursuant to Regulation S under the Securities Act of 1933, as amended.

RIGHTS. The Master Portfolio may purchase securities pursuant to the exercise of subscription rights, which allow an issuer's existing shareholders to purchase additional common stock at a price substantially below the market price of the shares.

SECURITIES LENDING. The Master Portfolio may lend securities with a value up to 33¹⁄₃% of its total assets to financial institutions that provide cash or securities issued or guaranteed by the U.S. Government as collateral.

SHORT-TERM DEBT SECURITIES. The Master Portfolio will normally invest a portion of its assets in short-term debt securities, such as commercial paper, money market securities, including repurchase agreements, or cash. As a temporary measure for defensive purposes, the Master Portfolio may invest in these securities without limitation. The Master Portfolio may also increase its investment in these securities or cash to meet redemptions. Investments in these short-term debt securities typically can be sold easily and have limited risk of loss but may limit the Master Portfolio's ability to achieve its investment objective.

STANDBY COMMITMENT AGREEMENTS. Standby commitment agreements commit the Master Portfolio, for a stated period of time, to purchase a stated amount of securities that may be issued and sold to the Master Portfolio at the option of the issuer.

TEMPORARY DEFENSIVE STRATEGIES. As a temporary measure for defensive purposes, the Master Portfolio may invest without limit in cash, cash equivalents or short-term U.S. Government securities. These investments may include high quality, short-term money market instruments such as U.S. Treasury and agency obligations, commercial paper (short-term, unsecured, negotiable promissory notes of a domestic or foreign company), short-term debt obligations of corporate issuers and certificates of deposit and bankers' acceptances. These investments may adversely affect the Master Portfolio's ability to meet its investment objective.

U.S. GOVERNMENT OBLIGATIONS. The Master Portfolio may invest in debt of the United States government.

WARRANTS. A warrant gives the Master Portfolio the right to buy stock. The warrant specifies the amount of underlying stock, the purchase (or "exercise") price, and the date the warrant expires. The Master Portfolio has no obligation to exercise the warrant and buy the stock. A warrant has value only if the Master Portfolio is able to exercise it or sell it before it expires.

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WHEN-ISSUED AND DELAYED DELIVERY SECURITIES AND FORWARD COMMITMENTS. The purchase or sale of securities on a when-issued basis or on a delayed delivery basis or through a forward commitment involves the purchase or sale of securities by the Master Portfolio at an established price with payment and delivery taking place in the future. The Master Portfolio enters into these transactions to obtain what is considered an advantageous price to the Master Portfolio at the time of entering into the transaction.

INVESTMENT RISKS

This section contains a discussion of the general risks of investing in the Master Portfolio. As with any fund, there can be no guarantee that the Master Portfolio will meet its investment objective or that the Master Portfolio's performance will be positive for any period of time. An investment in the Master Portfolio is not a deposit in any bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or by any bank or governmental agency. The order of the below risk factors does not indicate the significance of any particular risk factor.

PRINCIPAL RISKS OF INVESTING IN THE MASTER PORTFOLIO

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.

DERIVATIVES RISK. The Master Portfolio's use of derivatives may increase its costs, reduce the Master Portfolio's returns and/or increase volatility. Derivatives involve significant risks, including:

Leverage Risk - The Master Portfolio's use of derivatives can magnify the Master Portfolio'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 Master Portfolio could also suffer losses related to its derivatives positions as a result of unanticipated market movements, which losses are potentially unlimited. Finally, BFA may not be able to predict correctly the direction of securities prices, interest rates and other economic factors, which could cause the Master Portfolio'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 Master Portfolio to sell or otherwise close a derivatives position could expose the Master Portfolio to losses and could make derivatives more difficult for the Master Portfolio 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.

Volatility and Correlation Risk - The Master Portfolio's use of derivatives may reduce the Master Portfolio's returns and/or increase volatility. 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 Master Portfolio'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. Derivatives may also expose the Master Portfolio to greater risk and increase its costs. Certain transactions in derivatives involve substantial leverage risk and may expose the Master Portfolio to potential losses that exceed the amount originally invested by the Master Portfolio.

Hedging Risk - When a derivative is used as a hedge against a position that the Master Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. While hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Master Portfolio's hedging transactions will be effective. The use of hedging may result in certain adverse tax consequences noted below.

Tax Risk - The federal income tax treatment of a derivative may not be as favorable as a direct investment in an underlying asset and may adversely affect the timing, character and amount of income the Master Portfolio realizes from its investments. As a result, a larger portion of each interestholder's allocable share of income and gain may be treated as ordinary income rather than capital gains. In addition, certain derivatives are subject to mark-to-market or straddle provisions of the Internal Revenue Code of 1986, as amended (the "Internal Revenue Code"). If such provisions are applicable, there could be an increase (or decrease) in the amount of taxable dividends paid by a feeder fund. In addition, the tax treatment of certain derivatives, such as swaps, is unsettled and may be subject to future legislation, regulation or administrative pronouncements issued by the Internal Revenue Service.

Regulatory Risk - Derivative contracts are subject to regulation under the Dodd-Frank Wall Street Reform and Consumer Protection Act (the "Dodd-Frank Act") in the United States and under comparable regimes in Europe, Asia and other non-U.S. jurisdictions. Under the Dodd-Frank Act, with respect to uncleared swaps, swap dealers are required to collect variation margin from the Master Portfolio and may be required by applicable regulations to collect initial margin from the Master Portfolio. Both initial and variation margin may be comprised of cash and/or securities, subject to applicable regulatory haircuts. Shares of investment companies (other than certain money market funds) may not be posted as collateral under applicable regulations. In addition, regulations adopted by global prudential regulators that are now in effect require certain bank-regulated counterparties and certain of their affiliates to include in certain financial contracts, including many derivatives contracts, terms that delay or restrict the rights of counterparties, such as the Master Portfolio, to terminate such contracts, foreclose upon collateral, exercise other default rights or restrict transfers of credit support in the event that the counterparty and/or its affiliates are subject to certain types of resolution or insolvency proceedings. The implementation of these requirements with respect to derivatives, as well as regulations under the Dodd-Frank Act regarding clearing, mandatory trading and margining of other derivatives, may increase the costs and risks to the Master Portfolio of trading in these instruments and, as a result, may affect returns to investors in the Master Portfolio.

Future regulatory developments may impact the Master Portfolio's ability to invest or remain invested in certain derivatives. Legislation or regulation may also change the way in which the Master Portfolio itself is regulated. BFA cannot predict the effects of any new governmental regulation that may be implemented on the ability of the Master Portfolio to use swaps or any other financial derivative product, and there can be no assurance that any new governmental regulation will not adversely affect the Master Portfolio's ability to achieve its investment objective.

RISKS SPECIFIC TO CERTAIN DERIVATIVES USED BY THE MASTER PORTFOLIO

Swaps - Swap agreements, including total return swaps that may be referred to as contracts for difference, are two-party contracts entered into for periods ranging from a few days to more than one year. In a standard "swap" transaction, two parties agree to exchange the value(s) or cash flow(s) of one asset for another over a certain period of time. Swap agreements involve the risk that the party with whom the Master Portfolio has entered into the swap will default on its obligation to pay the Master Portfolio and the risk that the Master Portfolio will not be able to meet its obligations to pay the other party to the agreement. Swap agreements may also involve the risk that there is an imperfect correlation between the return on the Master Portfolio's obligation to its counterparty and the return on the referenced asset. In addition, swap agreements are subject to market and illiquidity risk, leverage risk and hedging risk.

Forward Foreign Currency Exchange Contracts - Forward foreign currency exchange transactions are OTC contracts to purchase or sell a specified amount of a specified currency or multinational currency unit at a price and future date set at the time of the contract. Forward foreign currency exchange contracts do not eliminate fluctuations in the value of non-U.S. securities but rather allow the Master Portfolio to establish a fixed rate of exchange for a future point in time. This strategy can have the effect of reducing returns and minimizing opportunities for gain.

Futures - Futures are standardized, exchange-traded contracts that obligate a purchaser to take delivery, and a seller to make delivery, of a specific amount of an asset at a specified future date at a specified price. The primary risks associated with the use of futures contracts and options are: (a) the imperfect correlation between the change in market value of the instruments held by the Master Portfolio and the price of the futures contract or option; (b) the possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (c) losses caused by unanticipated market movements, which are potentially unlimited; (d) the investment adviser's inability to predict correctly the direction of securities prices, interest rates, currency exchange rates and other economic factors; and (e) the possibility that the counterparty will default in the performance of its obligations.

Options - An option is an agreement that, for a premium payment or fee, gives the option holder (the purchaser) the right but not the obligation to buy (a "call option") or sell (a "put option") the underlying asset (or settle for cash in an amount based on an underlying asset, rate, or index) at a specified price (the "exercise price") during a period of time or on a specified date. Investments in options are considered speculative. When the Master Portfolio purchases an option, it may lose the total premium paid for it if the price of the underlying security or other assets decreased, remained the same or failed to increase to a level at or beyond the exercise price (in the case of a call option) or increased, remained the same or failed to decrease to a level at or below the exercise price (in the case of a put option). If a put or call option purchased by the Master Portfolio were permitted to expire without being sold or exercised, its premium would represent a loss to the Master Portfolio. To the extent that the Master Portfolio writes or sells an option, if the decline or increase in the underlying asset is significantly below or above the exercise price of the written option, the Master Portfolio could experience a substantial loss.

EMERGING MARKETS RISK. The risks of foreign investments are usually much greater for emerging markets. Investments in emerging markets may be considered speculative. Emerging markets may include those in countries considered emerging or developing by the World Bank, the International Finance Corporation or the United Nations. Emerging markets are riskier than more developed markets because they tend to develop unevenly and may never fully develop. They are more likely to experience hyperinflation and currency devaluations, which adversely affect returns to U.S. investors. In addition, many emerging markets have far lower trading volumes and less liquidity than developed markets. Since these markets are often small, they may be more likely to suffer sharp and frequent price changes or long-term price depression because of adverse publicity, investor perceptions or the actions of a few large investors. In addition, traditional measures of investment value used in the United States, such as price to earnings ratios, may not apply to certain small markets. Also, there may be less publicly available information about issuers in emerging markets than would be available about issuers in more developed capital markets, and such issuers may not be subject to accounting, auditing and financial reporting standards and requirements comparable to those to which U.S. companies are subject.

Many emerging markets have histories of political instability and abrupt changes in policies. As a result, their governments are more likely to take actions that are hostile or detrimental to private enterprise or foreign investment than those of more developed countries, including expropriation of assets, confiscatory taxation, high rates of inflation or unfavorable diplomatic developments. In the past, governments of such nations have expropriated substantial amounts of private property, and most claims of the property owners have never been fully settled. There is no assurance that such expropriations will not reoccur. In such an event, it is possible that the Master Portfolio could lose the entire value of its investments in the affected market. Some countries have pervasive corruption and crime that may hinder investments. Certain emerging markets may also face other significant internal or external risks, including the risk of war, and ethnic, religious and racial conflicts. In addition, governments in many emerging market countries participate to a significant degree in their economies and securities markets, which may impair investment and economic growth. National policies that may limit the Master Portfolio's investment opportunities include restrictions on investment in issuers or industries deemed sensitive to national interests.

Emerging markets may also have differing legal systems and the existence or possible imposition of exchange controls, custodial restrictions or other foreign or U.S. governmental laws or restrictions applicable to such investments. Sometimes, they may lack or be in the relatively early development of legal structures governing private and foreign investments and private property. Many emerging markets do not have income tax treaties with the United States, and as a result, investments by the Master Portfolio may be subject to higher withholding taxes in such countries. In addition, some countries with emerging markets may impose differential capital gains taxes on foreign investors. Foreign companies with securities listed on U.S. exchanges may be delisted if they do not meet U.S. accounting standards and auditor oversight requirements, which may significantly decrease the liquidity and value of the securities.

Practices in relation to settlement of securities transactions in emerging markets involve higher risks than those in developed markets, in part because the Master Portfolio will need to use brokers and counterparties that are less well capitalized, and custody and registration of assets in some countries may be unreliable. The possibility of fraud, negligence, undue influence being exerted by the issuer or refusal to recognize ownership exists in some emerging markets, and, along with other factors, could result in ownership registration being completely lost. The Master Portfolio would absorb any loss resulting from such registration problems and may have no successful claim for compensation. In addition, communications between the United States and emerging market countries may be unreliable, increasing the risk of delayed settlements or losses of security certificates.

EQUITY SECURITIES RISK. Common and preferred stocks represent equity ownership in a company. Stock markets are volatile. The price of equity securities will fluctuate and can decline and reduce the value of a portfolio investing in equities. The value of equity securities purchased by the Master Portfolio could decline if the financial condition of the companies the Master Portfolio invests in declines or if overall market and economic conditions deteriorate. The value of equity securities may also decline due to factors that affect a particular industry or industries, such as labor shortages or an increase in production costs and competitive conditions within an industry. In addition, the value may decline due to general market conditions that are not specifically related to a company or industry, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in inflation, interest or currency rates or generally adverse investor sentiment.

FOREIGN SECURITIES RISK. Securities traded in foreign markets have often (though not always) performed differently from securities traded in the United States. However, such investments often involve special risks not present in U.S. investments that can increase the chances that the Master Portfolio will lose money. In particular, the Master Portfolio is subject to the risk that because there may be fewer investors on foreign exchanges and a smaller number of securities traded each day, it may be more difficult for the Master Portfolio to buy and sell securities on those exchanges. In addition, prices of foreign securities may go up and down more than prices of securities traded in the United States.

Certain Risks of Holding Master Portfolio Assets Outside the United States - The Master Portfolio generally holds its foreign securities and cash in foreign banks and securities depositories. Some foreign banks and securities depositories may be recently organized or new to the foreign custody business. In addition, there may be limited or no regulatory oversight of their operations. Also, the laws of certain countries limit the Master Portfolio's ability to recover its assets if a foreign bank, depository or issuer of a security, or any of their agents, goes bankrupt. In addition, it is often more expensive for the Master Portfolio to buy, sell and hold securities in certain foreign markets than in the United States. The increased expense of investing in foreign markets reduces the amount the Master Portfolio can earn on its investments and typically results in a higher operating expense ratio for the Master Portfolio than for investment companies invested only in the United States.

Currency Risk - Securities and other instruments in which the Master Portfolio invests may be denominated or quoted in currencies other than the U.S. dollar. For this reason, changes in foreign currency exchange rates can affect the value of the Master Portfolio's portfolio.

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Generally, when the U.S. dollar rises in value against a foreign currency, a security denominated in that currency loses value because the currency is worth fewer U.S. dollars. Conversely, when the U.S. dollar decreases in value against a foreign currency, a security denominated in that currency gains value because the currency is worth more U.S. dollars. This risk, generally known as "currency risk," means that a strong U.S. dollar will reduce returns for U.S. investors while a weak U.S. dollar will increase those returns.

Foreign Economy Risk - 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. Certain foreign economies may rely heavily on particular industries or foreign capital and are more vulnerable to diplomatic developments, the imposition of economic sanctions against a particular country or countries, changes in international trading patterns, trade barriers and other protectionist or retaliatory measures. Investments in foreign markets may also be adversely affected by governmental actions such as the imposition of capital controls, nationalization of companies or industries, expropriation of assets or the imposition of punitive taxes. In addition, economic conditions, such as volatile currency exchange rates and interest rates, political events, military action and other conditions may, without prior warning, lead to the governments of certain countries, or the U.S. Government with respect to certain countries, prohibiting or imposing substantial restrictions through capital controls and/or sanctions on foreign investments in the capital markets or certain industries in those countries. Capital controls and/or sanctions may include the prohibition of, or restrictions on, the ability to own or transfer currency, securities, derivatives or other assets and may also include retaliatory actions of one government against another government, such as seizure of assets. Any of these actions could severely impair the Master Portfolio's ability to purchase, sell, transfer, receive, deliver or otherwise obtain exposure to foreign securities and assets, including the ability to transfer the Master Portfolio's assets or income back into the United States, and could negatively impact the value and/or liquidity of such assets or otherwise adversely affect the Master Portfolio's operations, causing the Master Portfolio to decline in value.

Other potential foreign market risks include foreign exchange controls, difficulties in pricing securities, defaults on foreign government securities, difficulties in enforcing legal judgments in foreign courts and political and social instability. Diplomatic and political developments, including rapid and adverse political changes, social instability, regional conflicts, terrorism and war, could affect the economies, industries and securities and currency markets, and the value of the Master Portfolio's investments, in non-U.S. countries. These factors are extremely difficult, if not impossible, to predict and take into account with respect to the Master Portfolio's investments.

Governmental Supervision and Regulation/Accounting Standards - Many foreign governments do not supervise and regulate stock exchanges, brokers and the sale of securities to the same extent as such regulations exist in the United States. They also may not have laws to protect investors that are comparable to U.S. securities laws. For example, some foreign countries may have no laws or rules against insider trading. Insider trading occurs when a person buys or sells a company's securities based on material non-public information about that company. In addition, some countries may have legal systems that may make it difficult for the Master Portfolio to vote proxies, exercise shareholder rights, and pursue legal remedies with respect to its foreign investments. Accounting standards in other countries are not necessarily the same as in the United States. If the accounting standards in another country do not require as much detail as U.S. accounting standards, it may be harder for Master Portfolio management to completely and accurately determine a company's financial condition.

Settlement Risk - Settlement and clearance procedures in certain foreign markets differ significantly from those in the United States. Foreign settlement and clearance procedures and trade regulations also may involve certain risks (such as delays in payment for or delivery of securities) not typically associated with the settlement of U.S. investments.

At times, settlements in certain foreign countries have not kept pace with the number of securities transactions. These problems may make it difficult for the Master Portfolio to carry out

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transactions. If the Master Portfolio cannot settle or is delayed in settling a purchase of securities, it may miss attractive investment opportunities and certain of its assets may be uninvested with no return earned thereon for some period. If the Master Portfolio cannot settle or is delayed in settling a sale of securities, it may lose money if the value of the security then declines or, if it has contracted to sell the security to another party, the Master Portfolio could be liable for any losses incurred.

Withholding Tax Reclaims Risk - The Master Portfolio may file claims to recover foreign withholding taxes on dividend and interest income (if any) received from issuers in certain countries and capital gains on the disposition of stocks or securities where such withholding tax reclaim is possible. Whether or when the Master Portfolio will receive a withholding tax refund is within the control of the tax authorities in such countries. Where the Master Portfolio expects to recover withholding taxes, the NAV of the Master Portfolio generally includes accruals for such tax refunds. The Master Portfolio regularly evaluates the probability of recovery. If the likelihood of recovery materially decreases, due to, for example, a change in tax regulation or approach in the foreign country, accruals in the Master Portfolio's NAV for such refunds may be written down partially or in full, which will adversely affect the Master Portfolio's NAV. Interestholders in the Master Portfolio at the time an accrual is written down will bear the impact of the resulting reduction in NAV regardless of whether they were interestholders during the accrual period. Conversely, if the Master Portfolio receives a tax refund that has not been previously accrued, interestholders in the Master Portfolio at the time of the successful recovery will benefit from the resulting increase in the Master Portfolio's NAV. Interestholders who sold their interests prior to such time will not benefit from such increase in the Master Portfolio's NAV.

European Economic Risk - 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 Master Portfolio's investments.

Responses to the financial problems by European governments, central banks and others, including austerity measures and reforms, may not work, may result in social unrest and may limit future growth and economic recovery or have other unintended consequences. Further defaults or restructurings by governments and others of their debt could have additional adverse effects on economies, financial markets and asset valuations around the world.

The United Kingdom has withdrawn from the European Union, and one or more other countries may withdraw from the European Union and/or abandon the Euro, the common currency of the European Union. These events and actions have adversely affected, and may in the future adversely affect, the value and exchange rate of the Euro and may continue to significantly affect the economies of every country in Europe, including countries that do not use the Euro and non-European Union member states. The impact of these actions, especially if they occur in a disorderly fashion, is not clear but could be significant and far reaching. In addition, Russia launched a large-scale invasion of Ukraine on February 24, 2022. The extent and duration of the military action, resulting sanctions and resulting future market disruptions in the region are impossible to predict, but could be significant and have a severe adverse effect on the region, including significant negative impacts on the economy and the markets for certain securities and commodities, such as oil and natural gas, as well as other sectors.

HIGH PORTFOLIO TURNOVER RISK. The Master Portfolio may engage in active and frequent trading of its portfolio securities. High portfolio turnover (more than 100%) may result in increased transaction costs to the Master Portfolio, including brokerage commissions, dealer mark-ups and other transaction costs on the sale of the securities and on reinvestment in other securities. The sale of Master Portfolio portfolio securities may result in the realization and/or distribution to shareholders of higher capital gains or losses as compared to a fund with less active trading policies. These effects of higher than normal portfolio turnover may adversely affect Master Portfolio performance.

INDEXED AND INVERSE SECURITIES RISK. Indexed and inverse securities provide a potential return based on a particular index of value or interest rates. The Master Portfolio'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 Master Portfolio's investment in such instruments may decline significantly in value if interest rates or index levels move in a way Master Portfolio management does not anticipate.

INVESTMENT STYLE RISK. Under certain market conditions, growth investments have performed better during the later stages of economic expansion and value investments have performed better during periods of economic recovery. Therefore, these investment styles may over time go in and out of favor. At times when the investment style used by the Master Portfolio is out of favor, the Master Portfolio may underperform other equity funds that use different investment styles.

LEVERAGE RISK. Some transactions may give rise to a form of economic leverage. These transactions may include, among others, derivatives, and may expose the Master Portfolio to greater risk and increase its costs. As an open-end investment company registered with the Securities and Exchange Commission (the "SEC"), the Master Portfolio is subject to the federal securities laws, including the 1940 Act and the rules thereunder. Under Rule 18f-4 under the 1940 Act, among other things, the Master Portfolio must either use derivatives in a limited manner or comply with an outer limit on fund leverage risk based on value-at-risk. The use of leverage may cause the Master Portfolio 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 1940 Act and the rules thereunder. Increases and decreases in the value of the Master Portfolio's portfolio will be magnified when the Master Portfolio uses leverage.

MARKET RISK AND SELECTION RISK.Market risk is the risk that one or more markets in which the Master Portfolio 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 Master Portfolio and its investments. Selection risk is the risk that the securities selected by Master Portfolio 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.

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.

RISK OF INVESTING IN THE UNITED STATES. A decrease in imports or exports, changes in trade regulations, inflation and/or an economic recession in the United States may have a material adverse effect on the U.S. economy and the securities listed on U.S. exchanges. Proposed and adopted policy and legislative changes in the United States are changing many aspects of financial, commercial, public health, environmental, and other regulation and may have a significant effect on U.S. markets generally, as well as on the value of certain securities. Governmental agencies project that the United States will continue to maintain elevated public debt levels for the foreseeable future. Although elevated debt levels do not necessarily indicate or cause economic problems, elevated public debt service costs may constrain future economic growth.

The United States has developed increasingly strained relations with a number of foreign countries. If relations with certain countries deteriorate, it could adversely affect U.S. issuers as well as non-U.S. issuers that rely on the United States for trade. The United States has also experienced increased internal political discord, as well as significant challenges in managing and containing the outbreak of COVID-19. If these trends were to continue, it may have an adverse impact on the U.S. economy and the issuers in which the Master Portfolio invests.

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 small number of key personnel. If a product fails or there are other adverse developments, or if management changes, the Master Portfolio's investment in a small cap or emerging growth company may lose substantial value. In addition, it is more difficult to get information on smaller companies, which tend to be less well known, have shorter operating histories, do not have significant ownership by large investors and are followed by relatively few securities analysts.

The securities of small cap and emerging growth companies generally trade in lower volumes and are subject to greater and more unpredictable price changes than larger cap securities or the market as a whole. In addition, small cap and emerging growth securities may be particularly sensitive to changes in interest rates, borrowing costs and earnings. Investing in small cap and emerging growth securities requires a longer term view.

OTHER RISKS OF INVESTING IN THE MASTER PORTFOLIO

The Master Portfolio may also be subject to certain other non-principal risks associated with its investments and investment strategies, including:

BORROWING RISK. Borrowing may exaggerate changes in the NAV of Master Portfolio interests and in the return on the Master Portfolio's portfolio. Borrowing will cost the Master Portfolio interest expense and other fees. The costs of borrowing may reduce the Master Portfolio's return. Borrowing may cause the Master Portfolio to liquidate positions when it may not be advantageous to do so to satisfy its obligations.

CYBER SECURITY RISK.Failures or breaches of the electronic systems of the Master Portfolio, the Master Portfolio's adviser, distributor, and other service providers, or the issuers of securities in which the Master Portfolio invests have the ability to cause disruptions and negatively impact the Master Portfolio's business operations, potentially resulting in financial losses to the Master Portfolio and its interestholders. While the Master Portfolio has established business continuity plans and risk management systems seeking to address system breaches or failures, there are inherent limitations in such plans and systems. Furthermore, the Master Portfolio cannot control the cyber security plans and systems of the Master Portfolio's service providers or issuers of securities in which the Master Portfolio invests.

DEBT SECURITIES RISK. Debt securities, such as bonds, involve credit risk. Credit risk refers to the possibility that the issuer of a debt security (i.e., the borrower) will not be able to make payments of interest and principal when due. Changes in an issuer's credit rating or the market's perception of an issuer's creditworthiness may also affect the value of the Master Portfolio's investment in that issuer. The degree of credit risk depends on both the financial condition of the issuer and the terms of the obligation. Debt securities are also subject to interest rate risk. Interest rate risk is the risk that the value of a debt security may fall when interest rates rise. In general, the market price of debt securities with longer maturities will go up or down more in response to changes in interest rates than the market price of shorter term securities. The Master Portfolio may be subject to a greater risk of rising interest rates due to the recent period of historically low interest rates. The Federal Reserve has recently begun to raise the federal funds rate as part of its efforts to address rising inflation. There is a risk that interest rates will continue to rise, which will likely drive down the prices of bonds and other fixed-income securities.

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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 Master Portfolio 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.

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EXPENSE RISK. Master Portfolio expenses are subject to a variety of factors, including fluctuations in the Master Portfolio's net assets. Accordingly, actual expenses may be greater or less than those indicated. For example, to the extent that the Master Portfolio's net assets decrease due to market declines or redemptions, the Master Portfolio's expenses will increase as a percentage of Master Portfolio net assets. During periods of high market volatility, these increases in the Master Portfolio's expense ratio could be significant.

ILLIQUID INVESTMENTS RISK.The Master Portfolio may not acquire any illiquid investment if, immediately after the acquisition, the Master Portfolio would have invested more than 15% of its net assets in illiquid investments. An illiquid investment is any investment that the Master Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Liquid investments may become illiquid after purchase by the Master Portfolio, particularly during periods of market turmoil. There can be no assurance that a security or instrument that is deemed to be liquid when purchased will continue to be liquid for as long as it is held by the Master Portfolio, and any security or instrument held by the Master Portfolio may be deemed an illiquid investment pursuant to the Master Portfolio's liquidity risk management program. The Master Portfolio's illiquid investments may reduce the returns of the Master Portfolio because it may be difficult to sell the illiquid investments at an advantageous time or price. In addition, if the Master Portfolio is limited in its ability to sell illiquid investments during periods when interestholders are redeeming their shares, the Master Portfolio will need to sell liquid securities to meet redemption requests and illiquid securities will become a larger portion of the Master Portfolio's holdings. An investment may be illiquid due to, among other things, the lack of an active trading market. To the extent that the Master Portfolio's principal investment strategies involve derivatives or securities with substantial market and/or credit risk, the Master Portfolio will tend to have the greatest exposure to the risks associated with illiquid investments. Illiquid investments may be harder to value, especially in changing markets, and if the Master Portfolio is forced to sell these investments to meet redemption requests or for other cash needs, the Master Portfolio may suffer a loss. In addition, when there is illiquidity in the market for certain securities, the Master Portfolio, due to limitations on illiquid investments, may be subject to purchase and sale restrictions.

INVESTMENT IN OTHER INVESTMENT COMPANIES RISK. As with other investments, investments in other investment companies, including ETFs, are subject to market and selection risk. In addition, if the Master Portfolio acquires shares of investment companies, including ones affiliated with the Master Portfolio, interestholders bear both their proportionate share of expenses in the Master Portfolio (including management and advisory fees) and, indirectly, the expenses of the investment companies (to the extent not offset by BFA through waivers). To the extent the Master Portfolio is held by an affiliated fund, the ability of the Master Portfolio itself to hold other investment companies may be limited.

LARGE SHAREHOLDER AND LARGE-SCALE REDEMPTION RISK. Certain interestholders, including a feeder fund, a third-party investor, the Master Portfolio's adviser or an affiliate of the Master Portfolio's adviser, or another entity, may from time to time own or manage a substantial amount of Master Portfolio interests or may invest in the Master Portfolio and hold its investment for a limited period of time. There can be no assurance that any large interestholder or large group of interestholders would not redeem their investment or that the size of the Master Portfolio would be maintained. If a large number of shares of a feeder fund that is a large interestholder are redeemed by the feeder fund's shareholders, the feeder fund may be required to redeem a large number of its Master Portfolio interests. Redemptions of a large number of Master Portfolio interests by a large interestholder or large group of interestholders may adversely affect the Master Portfolio's liquidity and net assets. These redemptions may force the Master Portfolio to sell portfolio securities to meet redemption requests when it might not otherwise do so, which may negatively impact the Master Portfolio's NAV and increase the Master Portfolio's brokerage costs and/or accelerate the realization of taxable income by interestholders earlier than the interestholders otherwise would have. The Master Portfolio also may be required to sell its more liquid investments to meet a large redemption, in which case the Master Portfolio's remaining assets may be less liquid, more volatile, and more difficult to price. In addition, large redemptions can result in the Master Portfolio's current expenses being allocated over a smaller asset base, which generally results in an increase in the Master Portfolio's expense ratio. Because large redemptions can adversely affect a portfolio manager's ability to implement a fund's investment strategy, the Master Portfolio also reserves the right to redeem in-kind, subject to certain conditions. In addition, large purchases of Master Portfolio interests may adversely affect the Master Portfolio's performance to the extent that the Master Portfolio is delayed in investing new cash and is required to maintain a larger cash position than it ordinarily would, diluting its investment returns.

MASTER LIMITED PARTNERSHIPS RISK. The common units of an MLP are listed and traded on U.S. securities exchanges and their value fluctuates predominantly based on prevailing market conditions and the success of the MLP. Unlike owners of common stock of a corporation, owners of common units have limited voting rights and have no ability to annually elect directors. In the event of liquidation, common units have preference over subordinated units, but not over debt or preferred units, to the remaining assets of the MLP.

"NEW ISSUES" RISK."New issues" are IPOs of equity securities. Investments in companies that have recently gone public have the potential to produce substantial gains for the Master Portfolio. However, there is no assurance that the Master Portfolio will have access to profitable IPOs and therefore investors should not rely on these past gains as an indication of future performance. The investment performance of the Master Portfolio during periods when it is unable to invest significantly or at all in IPOs may be lower than during periods when the Master Portfolio is able to do so. In addition, as the Master Portfolio increases in size, the impact of IPOs on the Master Portfolio's performance will generally decrease. Securities issued in IPOs are subject to many of the same risks as investing in companies with smaller market capitalizations. Securities issued in IPOs have no trading history, and information about the companies may be available for very limited periods. In addition, the prices of securities sold in IPOs may be highly volatile or may decline shortly after the IPO. When an IPO is brought to the market, availability may be limited and the Master Portfolio may not be able to buy any shares at the offering price, or, if it is able to buy shares, it may not be able to buy as many shares at the offering price as it would like.

OPERATIONAL RISK. The Master Portfolio is exposed to operational risks arising from a number of factors, including, but not limited to, human errors, processing and communication errors, errors of the Master Portfolio's service providers, counterparties or other third parties, failed or inadequate internal or external processes, and technology or systems failures. The use of certain investment strategies that involve manual or additional processing, such as over-the-counter derivatives, increases these risks. While service providers are required to have appropriate operational risk management policies and procedures, their methods of operational risk management may differ from those of the Master Portfolio in the setting of priorities, the personnel and resources available or the effectiveness of relevant controls. The Master Portfolio and BFA seek to reduce these operational risks through controls, procedures and oversight. However, it is not possible to identify all of the operational risks that may affect the Master Portfolio or to develop processes and controls that completely eliminate or mitigate the occurrence or effects of such failures. The Master Portfolio, including its performance and continued operation, and its shareholders could be negatively impacted as a result.

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, changes in rent schedules, 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 Master Portfolio's real estate-related investments are concentrated in one geographic area or in one property type, the Master Portfolio 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 Master Portfolio 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. In addition to the risks facing real estate-related securities, such as a decline in property values due to increasing vacancies, a decline in rents resulting from unanticipated economic, legal or technological developments or a decline in the price of securities of real estate companies due to a failure of borrowers to pay their loans or poor management, 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 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, which allows REITs to reduce their corporate taxable income for dividends paid to their shareholders. Ordinary REIT dividends received by a feeder fund and distributed to a feeder fund's shareholders will generally be taxable as ordinary income and will not constitute "qualified dividend income." However, for tax years beginning after December 31, 2017 and before January 1, 2026, a non-corporate taxpayer who is a direct REIT shareholder may claim a 20% "qualified business income" deduction for ordinary REIT dividends, and a regulated investment company may report dividends as eligible for this deduction to the extent the regulated investment company's income is derived from ordinary REIT dividends (reduced by allocable regulated investment company expenses). A shareholder may treat the dividends as such provided the regulated investment company and the shareholder satisfy applicable holding period requirements.

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RELIANCE ON ADVISOR RISK. The Master Portfolio is dependent upon services and resources provided by BFA, and therefore BFA's parent, BlackRock, Inc. BFA is not required to devote its full time to the business of the Master Portfolio and there is no guarantee or requirement that any investment professional or other employee of BFA will allocate a substantial portion of his or her time to the Master Portfolio. The loss of, or changes in, BFA's personnel could have a negative effect on the performance or the continued operation of the Master Portfolio.

REPURCHASE AGREEMENTS AND PURCHASE AND SALE CONTRACTS RISK. If the other party to a repurchase agreement or purchase and sale contract defaults on its obligation under the agreement, the Master Portfolio may suffer delays and incur costs or lose money in exercising its rights under the agreement. If the seller fails to repurchase the security in either situation and the market value of the security declines, the Master Portfolio may lose money.

RESTRICTED SECURITIES RISK. Limitations on the resale of restricted securities may have an adverse effect on their marketability, and may prevent the Master Portfolio from disposing of them promptly at advantageous prices. Restricted securities may not be listed on an exchange and may have no active trading market. In order to sell such securities, the Master Portfolio may have to bear the expense of registering the securities for resale and the risk of substantial delays in effecting the registration. Other transaction costs may be higher for restricted securities than unrestricted securities. Restricted securities may be difficult to value because market quotations may not be readily available, and the securities may have significant volatility. Also, the Master Portfolio may get only limited information about the issuer of a given restricted security, and therefore may be less able to predict a loss. Certain restricted securities may involve a high degree of business and financial risk and may result in substantial losses to the Master Portfolio.

RIGHTS RISK. The failure to exercise subscription rights to purchase common stock would result in the dilution of the Master Portfolio's interest in the issuing company. The market for such rights is not well developed, and, accordingly, the Master Portfolio may not always realize full value on the sale of rights.

SECURITIES LENDING RISK. The Master Portfolio may engage in securities lending. Securities lending involves the risk that the Master Portfolio may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Master Portfolio could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. These events could also trigger adverse tax consequences for a feeder fund. BlackRock Institutional Trust Company, N.A. ("BTC"), the Master Portfolio's securities lending agent, will consider the tax impact to shareholders of substitute payments for dividends when managing the Master Portfolio's securities lending program.

STANDBY COMMITMENT AGREEMENTS RISK. Standby commitment agreements involve the risk that the security the Master Portfolio buys will lose value prior to its delivery to the Master Portfolio and will no longer be worth what the Master Portfolio has agreed to pay for it. These agreements also involve the risk that if the security goes up in value, the counterparty will decide not to issue the security. In this case, the Master Portfolio loses both the investment opportunity for the assets it set aside to pay for the security and any gain in the security's price.

U.S. GOVERNMENT OBLIGATIONS RISK. Not all U.S. Government securities are backed by the full faith and credit of the United States. Obligations of certain agencies, authorities, instrumentalities and sponsored enterprises of the U.S. Government are backed by the full faith and credit of the United States (e.g., the Government National Mortgage Association); other obligations are backed by the right of the issuer to borrow from the U.S. Treasury (e.g., the Federal Home Loan Banks) and others are supported by the discretionary authority of the U.S. Government to purchase an agency's obligations. Still others are backed only by the credit of the agency, authority, instrumentality or sponsored enterprise issuing the obligation. No assurance can be given that the U.S. Government would provide financial support to any of these entities if it is not obligated to do so by law. In addition, circumstances could arise that could prevent the timely payment of interest or principal on U.S. Government obligations, such as reaching the legislative "debt ceiling." Such non-payment could result in losses to the Master Portfolio and substantial negative consequences for the U.S. economy and the global financial system.

VALUATION RISK. The price the Master Portfolio could receive upon the sale of any particular portfolio investment may differ from the Master Portfolio's valuation of the investment, particularly for securities that trade in thin or volatile markets or that are valued using a fair valuation methodology or a price provided by an independent pricing service. As a result, the price received upon the sale of an investment may be less than the value ascribed by the Master Portfolio, and the Master Portfolio could realize a greater than expected loss or lesser than expected gain upon the sale of the investment. Pricing services that value fixed-income securities generally utilize a range of market-based and security-specific inputs and assumptions, as well as considerations about general market conditions, to establish a price. Pricing services generally value fixed-income securities assuming orderly transactions of an institutional round lot size, but may be held or transactions may be conducted in such securities in smaller, odd lot sizes. Odd lots may trade at lower prices than institutional round lots. The Master Portfolio's ability to value its investments may also be impacted by technological issues and/or errors by pricing services or other third-party service providers.

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 Master Portfolio 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.

WHEN-ISSUED AND DELAYED DELIVERY SECURITIES AND FORWARD COMMITMENTS RISKS. When-issued and delayed delivery securities and forward commitments involve the risk that the security the Master Portfolio buys will lose value prior to its delivery. There also is the risk that the security will not be issued or that the other party to the transaction will not meet its obligation. If this occurs, the Master Portfolio may lose both the investment opportunity for the assets it set aside to pay for the security and any gain in the security's price.

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PORTFOLIO HOLDINGS INFORMATION

A description of the Master Portfolio's policies and procedures with respect to disclosure of the Master Portfolio's portfolio holdings is available in Part B of the Master Portfolio's registration statement and is available free of charge by calling (800) 441-7762 (toll-free). See Item 16, "Description of the Master Portfolio and its Investments and Risks" in Part B for additional details.

ITEM 10.

MANAGEMENT, ORGANIZATION AND CAPITAL STRUCTURE.

INVESTMENT ADVISER

BFA serves as investment adviser to the Master Portfolio. BFA is located at 400 Howard Street, San Francisco, CA 94105. BFA is an indirect wholly-owned subsidiary of BlackRock, Inc. Based on March 31, 2024 figures, BFA and its affiliates provided investment advisory services for assets in excess of $10.472 trillion. BFA and its affiliates (collectively, "BlackRock") deal, trade and invest for their own accounts in the types of securities in which the Master Portfolio invests.

BFA manages the investment of the Master Portfolio's assets and provides the Master Portfolio with investment guidance and policy direction in connection with the daily portfolio management of the Master Portfolio, subject to the supervision of the Board of Trustees and in conformity with Delaware law and the stated policies of the Master Portfolio. BFA furnishes to the Board of Trustees periodic reports on the investment strategy and performance of the Master Portfolio.

For its services to the Master Portfolio, BFA is entitled to receive a maximum annual management fee (as a percentage of average daily net assets) calculated as follows:

Average Daily Net Assets		Rate of Management Fee
First $1 billion			0.25	%
$1 billion - $3 billion			0.24	%
$3 billion - $5 billion			0.23	%
$5 billion - $10 billion			0.22	%
Greater than $10 billion			0.21	%

From time to time, BFA may waive such fees for the Master Portfolio in whole or in part. Any such waiver will reduce the expenses of the Master Portfolio and, accordingly, have a favorable impact on its performance. Effective September 18, 2023, BFA has contractually agreed to waive 0.095% of its management fee payable by the Master Portfolio through June 30, 2025. Prior to September 18, 2023, such agreement to waive 0.095% of the Master Portfolio's management fee was voluntary. The contractual agreement may be terminated upon 90 days' notice by a majority of the non-interested trustees of MIP or by a vote of a majority of the outstanding voting securities of the Master Portfolio.

BFA has contractually agreed to waive the management fee with respect to any portion of the Master Portfolio's assets estimated to be attributable to investments in other equity and fixed-income mutual funds and ETFs managed by BFA or its affiliates that have a contractual management fee, through June 30, 2025. BFA has contractually agreed to waive its management fees by the amount of investment advisory fees the Master Portfolio pays to BFA indirectly through its investment in money market funds managed by BFA or its affiliates, through June 30, 2025. The contractual agreement may be terminated upon 90 days' notice by a majority of the non-interested trustees of MIP or by a vote of a majority of the outstanding voting securities of the Master Portfolio.

The fees and expenses of the Independent Trustees of MIP, counsel to the Independent Trustees of MIP and the independent registered public accounting firm that provides audit services in connection with the Master Portfolio (collectively referred to as the "MIP Independent Expenses") are paid directly by the Master Portfolio. Each of BAL and BFA, as applicable, has contractually undertaken to reimburse or provide an offsetting credit to the Master Portfolio for such MIP Independent Expenses through June 30, 2025. Each such contractual arrangement may not be terminated prior to July 1, 2025 without the consent of the Board of Trustees of MIP.

For the fiscal year ended December 31, 2023, BFA received management fees, net of any applicable waivers and/or any reimbursements, at the annual rate of 0.14% of the Master Portfolio's average daily net assets.

A discussion regarding the basis for the Board of Trustees' approval of the investment advisory agreement with BFA with respect to the Master Portfolio is available in the Master Portfolio's semi-annual report for the fiscal period ended June 30, 2023.

From time to time, a manager, analyst or other employee of BFA or its affiliates may express views regarding a particular asset class, company, security, industry, or market sector. The views expressed by any such person are the views of only that individual as of the time expressed and do not necessarily represent the views of BFA or any other person within the BFA organization. Any such views are subject to change at any time based upon market or other conditions and BFA disclaims any responsibility to update such views. These views may not be relied on as investment advice and, because investment decisions for the Master Portfolio are based on numerous factors, may not be relied on as an indication of trading intent on behalf of the Master Portfolio.

PORTFOLIO MANAGERS

Philip Green, Michael Pensky and Daniel Felder (the "Portfolio Managers") are jointly and primarily responsible for the day-to-day management of the Master Portfolio.

Information regarding the Portfolio Managers is set forth below. Further information regarding the Portfolio Managers, including other accounts managed, compensation, ownership of Master Portfolio interests, and possible conflicts of interest, is available in the Master Portfolio's Part B.

Portfolio Manager		Primary Role		Since		Title and Recent Biography
Philip Green		Jointly and primarily responsible for the day-to-day management of the Master Portfolio, including setting the Master Portfolio's overall investment strategy and overseeing the management of the Master Portfolio.		2016		Managing Director of BlackRock, Inc. since 2006.
Michael Pensky		Jointly and primarily responsible for the day to day management of the Master Portfolio, including setting the Master Portfolio's overall investment strategy and overseeing the management of the Master Portfolio.		2024		Managing Director of BlackRock, Inc. since 2021; Director of BlackRock, Inc. from 2018 to 2020; Vice President of BlackRock, Inc. from 2016 to 2017; Associate of BlackRock, Inc. from 2012 to 2015.
Daniel Felder		Jointly and primarily responsible for the day to day management of the Master Portfolio, including setting the Master Portfolio's overall investment strategy and overseeing the management of the Master Portfolio.		2024		Director of BlackRock, Inc. since 2021; Vice President of BlackRock, Inc. from 2017 to 2020; Associate of BlackRock, Inc. from 2014 to 2016; Analyst of BlackRock, Inc. from 2011 to 2013.

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ADMINISTRATOR

BlackRock Advisors, LLC ("BAL") serves as administrator of the Master Portfolio. BAL provides the Master Portfolio with administration services, including the provision of management reporting and treasury administration services, financial reporting, legal and tax services, and supervision of the Master Portfolio's administrative operations, preparation of proxy statements and interestholder reports. BAL also furnishes office space and certain facilities to conduct the Master Portfolio's business and compensates MIP's trustees, officers and employees who are affiliated with BAL. BAL is entitled to receive an annual administrative fee of 0.10% of the Master Portfolio's average daily net assets for providing administration services.

Effective September 18, 2023, BAL has contractually agreed to waive its administration fees through June 30, 2025. Prior to September 18, 2023, such agreement to waive its administration fees was voluntary. The contractual agreement may be terminated upon 90 days' notice by a majority of the non-interested trustees of MIP or by a vote of a majority of the outstanding voting securities of the Master Portfolio.

In addition to performing these services, BAL has agreed to bear all costs of the Master Portfolio's and MIP's operations, other than brokerage expenses, advisory fees, any 12b-1 fees, certain fees and expenses related to the members of the Board of Trustees who are not "interested persons" of MIP (as such term is defined in the 1940 Act) (the "Independent Trustees" and each, an "Independent Trustee") and their counsel, auditing fees, litigation expenses, taxes and extraordinary expenses.

CONFLICTS OF INTEREST

The investment activities of BFA and its affiliates (including BlackRock, Inc. and its subsidiaries (collectively, the "Affiliates")), and their respective directors, officers or employees, in the management of, or their interest in, their own accounts and other accounts they manage, may present conflicts of interest that could disadvantage the Master Portfolio and its interestholders.

BFA and its Affiliates provide investment management services to other funds and discretionary managed accounts that may follow investment programs similar to that of the Master Portfolio. BFA and its Affiliates are involved worldwide with a broad spectrum of financial services and asset management activities and may engage in the ordinary course of business in activities in which their interests or the interests of their clients may conflict with those of the Master Portfolio. BFA or one or more Affiliates act or may act as an investor, research provider, investment manager, commodity pool operator, commodity trading advisor, financier, underwriter, adviser, trader, lender, index provider, agent and/or principal, and have other direct and indirect interests in securities, currencies, commodities, derivatives and other instruments in which the Master Portfolio may directly or indirectly invest. The Master Portfolio may invest in securities of, or engage in other transactions with, companies with which an Affiliate has significant debt or equity investments or other interests. The Master Portfolio may also invest in issuances (such as structured notes) by entities for which an Affiliate provides and is compensated for cash management services relating to the proceeds from the sale of such issuances. The Master Portfolio also may invest in securities of, or engage in other transactions with, companies for which an Affiliate provides or may in the future provide research coverage. An Affiliate may have business relationships with, and purchase, or distribute or sell services or products from or to, distributors, consultants or others who recommend the Master Portfolio or who engage in transactions with or for the Master Portfolio, and may receive compensation for such services. BFA or one or more Affiliates may engage in proprietary trading and advise accounts and funds that have investment objectives similar to those of the Master Portfolio and/or that engage in and compete for transactions in the same types of securities, currencies and other instruments as the Master Portfolio. This may include transactions in securities issued by other open-end and closed-end investment companies (which may include investment companies that are affiliated with the Master Portfolio and BFA, to the extent permitted under the 1940 Act). The trading activities of BFA and these Affiliates are carried out without reference to positions held directly or indirectly by the Master Portfolio and may result in BFA or an Affiliate having positions in certain securities that are senior or junior to, or have interests different from or adverse to, the securities that are owned by the Master Portfolio.

Neither BFA nor any Affiliate is under any obligation to share any investment opportunity, idea or strategy with the Master Portfolio. As a result, an Affiliate may compete with the Master Portfolio for appropriate investment opportunities. The results of the Master Portfolio's investment activities, therefore, may differ from those of an Affiliate and of other accounts managed by BFA or an Affiliate, and it is possible that the Master Portfolio could sustain losses during periods in which one or more Affiliates and other accounts achieve profits on their trading for proprietary or other accounts. The opposite result is also possible.

In addition, the Master Portfolio may, from time to time, enter into transactions in which BFA or an Affiliate or their directors, officers or employees or other clients have an adverse interest. Furthermore, transactions undertaken by clients advised or managed by BFA or its Affiliates may adversely impact the Master Portfolio. Transactions by one or more clients or BFA or its Affiliates or their directors, officers or employees, may have the effect of diluting or otherwise disadvantaging the values, prices or investment strategies of the Master Portfolio. The Master Portfolio's activities may be limited because of regulatory restrictions applicable to BFA or one or more Affiliates and/or their internal policies designed to comply with such restrictions.

Under a securities lending program approved by the Board, MIP, on behalf of the Master Portfolio, has retained BlackRock Institutional Trust Company, N.A., an Affiliate of BFA, to serve as the securities lending agent for the Master Portfolio to the extent that the Master Portfolio participates in the securities lending program. For these services, the securities lending agent will receive a fee from the Master Portfolio based on the returns earned on the Master Portfolio's lending activities, including investment of the cash received as collateral for the loaned securities. In addition, one or more Affiliates may be among the entities to which the Master Portfolio may lend its portfolio securities under the securities lending program.

The activities of BFA and its Affiliates and their respective directors, officers or employees, may give rise to other conflicts of interest that could disadvantage the Master Portfolio and its interestholders. BFA has adopted policies and procedures designed to address these potential conflicts of interest. See the SAI for further information.

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ANTI-MONEY LAUNDERING REQUIREMENTS

The Master Portfolio is subject to the USA PATRIOT Act (the "Patriot Act"). The Patriot Act is intended to prevent the use of the U.S. financial system in furtherance of money laundering, terrorism or other illicit activities. Pursuant to requirements under the Patriot Act, the Master Portfolio is required to obtain sufficient information from interestholders to enable it to form a reasonable belief that it knows the true identity of its interestholders. This information will be used to verify the identity of investors or, in some cases, the status of financial intermediaries. Such information may be verified using third party sources. This information will be used only for compliance with the Patriot Act or other applicable laws, regulations and rules in connection with money laundering, terrorism or economic sanctions.

The Master Portfolio reserves the right to reject purchase orders from persons who have not submitted information sufficient to allow the Master Portfolio to verify their identity. The Master Portfolio also reserves the right to redeem any amounts in the Master Portfolio from persons whose identity it is unable to verify on a timely basis. It is the Master Portfolio's policy to cooperate fully with appropriate regulators in any investigations conducted with respect to potential money laundering, terrorism or other illicit activities.

BLACKROCK PRIVACY PRINCIPLES

BlackRock is committed to maintaining the privacy of its current and former fund investors and individual clients (collectively, "Clients") and to safeguarding their non-public personal information. The following information is provided to help you understand what personal information BlackRock collects, how we protect that information and why in certain cases we share such information with select parties.

If you are located in a jurisdiction where specific laws, rules or regulations require BlackRock to provide you with additional or different privacy-related rights beyond what is set forth below, then BlackRock will comply with those specific laws, rules or regulations.

BlackRock obtains or verifies personal non-public information from and about you from different sources, including the following: (i) information we receive from you or, if applicable, your financial intermediary, on applications, forms or other documents; (ii) information about your transactions with us, our affiliates, or others; (iii) information we receive from a consumer reporting agency; and (iv) from visits to our website.

BlackRock does not sell or disclose to non-affiliated third parties any non-public personal information about its Clients, except as permitted by law, or as is necessary to respond to regulatory requests or to service Client accounts. These non-affiliated third parties are required to protect the confidentiality and security of this information and to use it only for its intended purpose.

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We may share information with our affiliates to service your account or to provide you with information about other BlackRock products or services that may be of interest to you. In addition, BlackRock restricts access to non-public personal information about its Clients to those BlackRock employees with a legitimate business need for the information. BlackRock maintains physical, electronic and procedural safeguards that are designed to protect the non-public personal information of its Clients, including procedures relating to the proper storage and disposal of such information.

ORGANIZATION AND CAPITAL STRUCTURE

MIP was organized on October 20, 1993 as a statutory trust under the laws of the State of Delaware and is registered as an open-end, series management investment company under the 1940 Act. MIP is a "series fund," which is a mutual fund company that has been divided into separate portfolios. Each portfolio is treated as a separate entity for certain matters under the 1940 Act and for certain other purposes. An interestholder of the Master Portfolio is not deemed to be an interestholder of any other portfolio of MIP. The Board of Trustees has authorized MIP to issue multiple series. MIP currently offers interests in the following series: Diversified Equity Master Portfolio, International Tilts Master Portfolio, Large Cap Index Master Portfolio, Money Market Master Portfolio, S&P 500 Index Master Portfolio, Total International ex U.S. Index Master Portfolio, Treasury Money Market Master Portfolio and U.S. Total Bond Index Master Portfolio. Information about the listed portfolios that are not covered in this combined Part A and Part B is contained in separate offering documents. From time to time, additional portfolios may be established and sold pursuant to other offering documents.

All consideration received by MIP for interests in one of its portfolios and all assets in which such consideration is invested will belong to that portfolio (subject only to the rights of creditors of MIP) and will be subject to the liabilities related thereto. The income attributable to, and the expenses of, one portfolio are treated separately from those of each other portfolio.

The business and affairs of MIP are managed under the direction of its Board of Trustees. The office of MIP is located at BlackRock, Inc., 400 Howard Street, San Francisco, California 94105.

Please see Item 22 of Part B for a further description of MIP's capital structure.

ITEM 11.

INTERESTHOLDER INFORMATION.

PURCHASE, REDEMPTION AND PRICING OF INTERESTS

Investments in the Master Portfolio are valued based on an interestholder's proportionate ownership interest (rounded to the nearest hundredth of a percent, although the Master Portfolio reserves the right to calculate proportionate ownership interests to more than two decimal places) in the Master Portfolio's aggregate net assets ("Net Assets") (i.e., the value of its total assets (including the securities held by the Master Portfolio plus any cash or other assets, including interest and dividends accrued but not yet received) less total liabilities (including accrued expenses)) as next determined after an order is received in proper form. The value of the Master Portfolio's Net Assets is determined as of the close of regular trading on the NYSE, which is generally 4:00 p.m. (Eastern time) ("Valuation Time") on each day the NYSE is open for business (a "Business Day"). If the NYSE closes early, the time for calculating the Master Portfolio's NAV and the deadline for additions to or reductions in investments in the Master Portfolio will be accelerated to the earlier closing time.

An investor in the Master Portfolio may add to or reduce its investment in the Master Portfolio on any Business Day. At the Valuation Time on each Business Day, the value of each investor's beneficial interest in the Master Portfolio is determined by multiplying the Master Portfolio's Net Assets by the percentage, effective for that day, of that investor's share of the aggregate beneficial interests in the Master Portfolio. Any additions to or redemptions of those interests, which are to be effected on that day, will then be effected. Each investor's share of the aggregate beneficial interests in the Master Portfolio will then be recomputed using the percentage equal to the fraction of (i) the numerator of which is the value of the investor's cumulative investment in the Master Portfolio up to that day, plus or minus, as the case may be, the amounts of net additions or redemptions from such investment effected on that day and (ii) the denominator of which is the Master Portfolio's Net Assets as of the Valuation Time on that day, plus or minus, as the case may be, the amount of the net additions to or redemptions from the aggregate investments in the Master Portfolio by all investors. The percentages so determined are then applied to determine the value of each investor's respective interest in the Master Portfolio as of the Valuation Time on the following Business Day.

The value of the securities and other assets and liabilities held by the Master Portfolio are determined pursuant to BlackRock's valuation policies and procedures. BlackRock has been designated by the Board of Trustees as the valuation designee for the Master Portfolio pursuant to Rule 2a-5 under the 1940 Act.

Equity securities and other equity instruments for which market quotations are readily available are valued at market value, which is generally determined using the last reported official closing price or, if a reported closing price is not available, the last traded price on the exchange or market on which the security or instrument is primarily traded at the time of valuation. Shares of underlying open-end funds (including money market funds) are valued at NAV. Shares of underlying exchange-traded closed-end funds or other ETFs are valued at their most recent closing price.

The Master Portfolio values fixed-income portfolio securities using last available bid prices or current market quotations provided by dealers or prices (including evaluated prices) supplied by the Master Portfolio's approved independent third-party pricing services, each in accordance with BlackRock's valuation policies and procedures. Pricing services may use matrix pricing or valuation models that utilize certain inputs and assumptions to derive values. Pricing services generally value fixed-income securities assuming orderly transactions of an institutional round lot size, but the Master Portfolio may hold or transact in such securities in smaller odd lot sizes. Odd lots may trade at lower prices than institutional round lots. An amortized cost method of valuation may be used with respect to debt obligations with 60 days or less remaining to maturity unless BlackRock determines in good faith that such method does not represent fair value.

Generally, trading in non-U.S. securities, U.S. government securities, money market instruments and certain fixed income securities is substantially completed each day at various times prior to the close of business on the NYSE. The values of such securities used in computing the NAV of the Master Portfolio's interests are determined as of such times.

When market quotations are not readily available or are believed by BlackRock to be unreliable, BlackRock will fair value the Master Portfolio's investments in accordance with its policies and procedures. BlackRock may conclude that a market quotation is not readily available or is unreliable if a security or other asset or liability does not have a price source due to its lack of trading or other reasons, if a market quotation differs significantly from recent price quotations or otherwise no longer appears to reflect fair value, where the security or other asset or liability is thinly traded, when there is a significant event subsequent to the most recent market quotation, or if the trading market on which a security is listed is suspended or closed and no appropriate alternative trading market is available. A "significant event" is deemed to occur if BlackRock determines, in its reasonable business judgment prior to or at the time of pricing the Master Portfolio's assets or liabilities, that the event is likely to cause a material change to the closing market price of one or more assets held by, or liabilities of, the Master Portfolio.

For certain foreign assets, a third-party vendor supplies evaluated, systematic fair value pricing based upon the movement of a proprietary multi-factor model after the relevant foreign markets have closed. This systematic fair value pricing methodology is designed to correlate the prices of foreign assets following the close of the local markets to the price that might have prevailed as of the Master Portfolio's pricing time.

Fair value represents a good faith approximation of the value of an asset or liability. The fair value of an asset or liability held by the Master Portfolio is the amount the Master Portfolio might reasonably expect to receive from the current sale of that asset or the cost to extinguish that liability in an arm's-length transaction. Valuing the Master Portfolio's investments using fair value pricing will result in prices that may differ from current market valuations and that may not be the prices at which those investments could have been sold during the period in which the particular fair values were used.

The Master Portfolio may accept orders from certain authorized Financial Intermediaries or their designees. The Master Portfolio will be deemed to receive an order when accepted by the Financial Intermediary or designee, and the order will receive the NAV next computed by the Master Portfolio after such acceptance. If the payment for a purchase order is not made by a designated later time, the order will be cancelled and the Financial Intermediary could be held liable for any losses.

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An investor in the Master Portfolio may redeem all or any portion of its interest on any Business Day at the NAV next determined after a redemption request is received in proper form. The Master Portfolio generally remits the proceeds from a redemption the next Business Day after receiving a properly executed redemption order and no longer than seven days after receiving the order. MIP may, however, suspend the right of redemption or postpone redemption payments for longer than seven days for any period during which (i) the NYSE is closed (other than customary weekend and holiday closings); (ii) trading on the NYSE is restricted; (iii) an emergency exists as a result of which disposal or valuation of the Master Portfolio's investments is not reasonably practicable; or (iv) for such other periods as the SEC by order may permit, as permitted under Section 22(e) of the 1940 Act, and other applicable laws. In addition, the Master Portfolio reserves the right to refuse any purchase of interests. Investments in the Master Portfolio may not be transferred.

The Master Portfolio reserves the right to pay redemption proceeds in portfolio securities rather than cash. MIP has elected to be governed by Rule 18f-1 under the 1940 Act so that the Master Portfolio is obligated to redeem its interests solely in cash up to the lesser of $250,000 or 1% of the value of the Master Portfolio's Net Assets during any 90-day period for any interestholder of the Master Portfolio. The redemption price is the value of the Master Portfolio's Net Assets per share next determined after the initial receipt of proper notice of redemption.

Under normal circumstances, the Master Portfolio expects to meet redemption requests by using cash or cash equivalents in its portfolio or by selling portfolio assets to generate cash. During periods of stressed market conditions, when a significant portion of the Master Portfolio's portfolio may be comprised of less-liquid investments, the Master Portfolio may be more likely to limit cash redemptions and may determine to pay redemption proceeds by (i) borrowing under a line of credit it has entered into with a group of lenders, (ii) borrowing from another open-end BlackRock-advised fund pursuant to an interfund lending program, to the extent permitted by the Master Portfolio's investment policies and restrictions as set forth in Part B of this registration statement, and/or (iii) transferring portfolio securities in-kind to a feeder fund. Part B of this registration statement includes more information about the Master Portfolio's line of credit and interfund lending program, to the extent applicable.

If the Master Portfolio pays redemption proceeds by transferring portfolio securities in-kind to a feeder fund, the feeder fund may pay transaction costs to dispose of the securities, and the feeder fund may receive less for them than the price at which they were valued for purposes of redemption.

NET INVESTMENT INCOME AND CAPITAL GAIN ALLOCATIONS AND DISTRIBUTIONS

Any net investment income of the Master Portfolio generally will be accrued and allocated daily to all investors of record as of the Valuation Time on any Business Day. The Master Portfolio's net investment income for a Saturday, Sunday or holiday will be accrued and allocated to investors of record as of the Valuation Time on the previous Business Day. Allocations of the Master Portfolio's net investment income will be distributed to an interestholder's account on the applicable payment date. Any net capital gains realized by the Master Portfolio will be allocated on the date of accrual and distributed at least annually to an interestholder's account on the applicable payment date.

The Master Portfolio will allocate its investment income, expenses, and realized and unrealized net gains and losses to its interestholders pro rata in accordance with their beneficial interests. Allocations of taxable income or loss may be made in a different manner in order to comply with U.S. federal income tax rules.

SHORT-TERM TRADING POLICY

MIP does not offer its interests for sale to the general public, nor does it offer an exchange privilege. MIP is not, therefore, directly subject to the risks of short-term trading and the Board of Trustees has not adopted procedures to prevent such trading. However, MIP may be adversely affected by short-term trading in shares of a Feeder Fund. See "Account Information - Short-Term Trading Policy" in Part A of the BlackRock III Feeder Fund Registration Statement for more information.

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TAXES

The Master Portfolio has more than one feeder fund and intends to operate as a non-publicly traded partnership for U.S. federal income tax purposes. If the Master Portfolio had only one feeder fund (either (i) directly or (ii) indirectly through an entity that is disregarded for U.S. federal income tax purposes), then the Master Portfolio would be disregarded as an entity separate from that feeder fund.

Whether the Master Portfolio is a partnership or disregarded as a separate entity, it will generally not be subject to any U.S. federal income tax. Each of the Master Portfolio's feeder funds will take into account its allocable share of the Master Portfolio's ordinary income, capital gains, losses, deductions and credits in determining its income tax liability and, if the feeder fund is intended to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code, the feeder fund will take into account its allocable share of the Master Portfolio's income and assets for purposes of the feeder fund's gross income and asset diversification tests.

It is intended that the Master Portfolio's assets, income and distributions will be managed in such a way that each feeder fund will be able to satisfy the requirements of Subchapter M of the Internal Revenue Code for qualification as a regulated investment company, assuming that the feeder fund invests all of its investable assets in the Master Portfolio and the feeder fund meets all other requirements for such qualification not within the control of the Master Portfolio.

ITEM 12.

DISTRIBUTION ARRANGEMENTS.

Beneficial interests in the Master Portfolio are not registered under the 1933 Act because such interests are issued solely in transactions that are exempt from registration under the 1933 Act. The Master Portfolio is a "master" in a "master/feeder" structure. Only "feeder funds" (i.e., investment companies that are "accredited investors" and invest all of their assets in the Master Portfolio) or certain other entities that are "accredited investors" within the meaning of Regulation D under the 1933 Act may make direct investments in the Master Portfolio. BRIL is the placement agent for the Master Portfolio.

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A non-accredited investor may not directly purchase an interest in the Master Portfolio, but instead may purchase shares in a feeder fund that invests directly in the Master Portfolio. Any accredited investors other than feeder funds that invest in the Master Portfolio will do so on the same terms and conditions as the feeder funds, although they may have different administrative and other expenses. Therefore, some indirect investors may have different returns than other indirect investors in the Master Portfolio.

ITEM 13.

FINANCIAL HIGHLIGHTS.

The response to Item 13 has been omitted pursuant to General Instruction B, Paragraph 2(b), to Form N-1A under the 1940 Act.

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MASTER INVESTMENT PORTFOLIO

DIVERSIFIED EQUITY MASTER PORTFOLIO

PART B - STATEMENT OF ADDITIONAL INFORMATION

April 29, 2024

ITEM 14.

COVER PAGE AND TABLE OF CONTENTS.

Master Investment Portfolio ("MIP") is an open-end, series management investment company. MIP is a "series fund," which is a mutual fund company that has been divided into separate portfolios. This Part B is for Diversified Equity Master Portfolio (the "Master Portfolio"). This Part B is not a prospectus and should be read in conjunction with the combined Part A, also dated April 29, 2024, of the Master Portfolio. All terms used in this Part B that are defined in Part A have the meanings assigned in Part A of the Registration Statement with respect to the Master Portfolio, unless otherwise defined in Part B. MIP incorporates by reference the information included on the cover page of the statement of additional information of BlackRock Diversified Equity Fund (the "BlackRock Funds III Feeder Fund"), as amended, revised or supplemented from time to time (the "SAI"). A copy of Part A may be obtained without charge by writing to Master Investment Portfolio, c/o BNY Mellon Investment Servicing (US) Inc., P.O. Box 534429, Pittsburgh, Pennsylvania 15253-4429, or by calling (800) 441-7762. MIP's registration statement may be examined at the office of the Securities and Exchange Commission, ("SEC" or the "Commission") in Washington, D.C. NEITHER PART A NOR THIS PART B CONSTITUTES AN OFFER TO SELL, OR THE SOLICITATION OF AN OFFER TO BUY, ANY BENEFICIAL INTERESTS IN THE MASTER PORTFOLIO.

References to the Investment Company Act of 1940, as amended (the "1940 Act"), or other applicable law, will include any rules promulgated thereunder and any guidance, interpretations or modifications by the SEC, SEC staff or other authority with appropriate jurisdiction, including court interpretations, and exemptive, no-action or other relief or permission from the SEC, SEC staff or other authority.

The Master Portfolio is subject to Rule 35d-1 under the 1940 Act, and will not change its investment policies required by that Rule without giving shareholders 60 days' prior written notice.

B-1

TABLE OF CONTENTS

				PAGE
ITEM 15		TRUST HISTORY			B-2
ITEM 16		DESCRIPTION OF THE MASTER PORTFOLIO AND ITS INVESTMENTS AND RISKS			B-2
ITEM 17		MANAGEMENT OF THE TRUST			B-4
ITEM 18		CONTROL PERSONS AND PRINCIPAL HOLDERS OF SECURITIES			B-5
ITEM 19		INVESTMENT ADVISORY AND OTHER SERVICES			B-5
ITEM 20		PORTFOLIO MANAGERS			B-6
ITEM 21		BROKERAGE ALLOCATION AND OTHER PRACTICES			B-7
ITEM 22		CAPITAL STOCK AND OTHER INTERESTS			B-8
ITEM 23		PURCHASE, REDEMPTION AND PRICING OF INTERESTS			B-9
ITEM 24		TAXATION OF THE TRUST			B-10
ITEM 25		UNDERWRITERS			B-11
ITEM 26		CALCULATION OF PERFORMANCE DATA			B-12
ITEM 27		FINANCIAL STATEMENTS			B-12

ITEM 15.

TRUST HISTORY.

MIP is an open-end, series management investment company organized on October 20, 1993 as a statutory trust under the laws of the State of Delaware. MIP is a "series fund," which is a mutual fund company that has been divided into separate portfolios.

ITEM 16.

DESCRIPTION OF THE MASTER PORTFOLIO AND ITS INVESTMENTS AND RISKS.

The following information supplements and should be read in conjunction with Item 9 in Part A.

INVESTMENTS AND RISKS. MIP incorporates by reference the information concerning the Master Portfolio's additional investment strategies, risks and restrictions (including information on the Interfund Lending Program, under which the Master Portfolio has the ability to borrow or lend for temporary purposes) from the following sections of the SAI: "Investment Objectives and Policies," "Investment Risks and Considerations" and "Appendix A - Description of Bond Ratings."

PORTFOLIO HOLDINGS INFORMATION. MIP incorporates by reference the information concerning the Master Portfolio's policies and procedures with respect to the disclosure of portfolio holdings from the following sections of the SAI: "Selective Disclosure of Portfolio Holdings." Information on any significant variation or anticipated variation in the Master Portfolio's portfolio turnover rates, if any, is incorporated herein by reference to following section if the SAI: " Additional Information."

INVESTMENT RESTRICTIONS

FUNDAMENTAL INVESTMENT RESTRICTIONS. The Master Portfolio has adopted the following investment restrictions as fundamental policies. These restrictions cannot be changed, as to the Master Portfolio, without approval by the holders of a majority (as defined in the 1940 Act) of the Master Portfolio's outstanding voting interests. The Master Portfolio may not:

(1)

Purchase the securities of issuers conducting their principal business activity in the same industry if, immediately after the purchase and as a result thereof, the value of the Master Portfolio's investments in that industry would exceed 25% of the current value of the Master Portfolio's total assets, provided that this restriction does not limit the Master Portfolio's: (i) investments in securities of other investment companies, (ii) investments in securities issued or guaranteed by the U.S. government, its agencies or instrumentalities, or (iii) investments in repurchase agreements, provided further that the Master Portfolio reserves the right to concentrate in the obligations of domestic banks (as such term is interpreted by the SEC or its staff).

(2)

Purchase securities of any issuer if, as a result, with respect to 75% of the Master Portfolio's total assets, more than 5% of the value of its total assets would be invested in the securities of any one issuer or the Master Portfolio's ownership would be more than 10% of the outstanding voting securities of such issuer, provided that this restriction does not limit the Master Portfolio's investments in securities issued or guaranteed by the U.S. government, its agencies and instrumentalities, or investments in securities of other investment companies.

(3)	Borrow money, except to the extent permitted under the 1940 Act, including the rules, regulations and any orders obtained thereunder.

(4)	Issue senior securities, except to the extent permitted under the 1940 Act, including the rules, regulations and any orders obtained thereunder.

(5)

Make loans to other parties, except to the extent permitted under the 1940 Act, including the rules, regulations and any orders obtained thereunder. For the purposes of this limitation, entering into repurchase agreements, lending securities and acquiring any debt securities are not deemed to be the making of loans.

(6)

Underwrite securities of other issuers, except to the extent that the purchase of permitted investments directly from the issuer thereof or from an underwriter for an issuer and the later disposition of such securities in accordance with the Master Portfolio's investment program may be deemed to be an underwriting; and provided further, that the purchase by the Master Portfolio of securities issued by an open-end management investment company, or a series thereof, with substantially the same investment objective, policies and restrictions as the Master Portfolio shall not constitute an underwriting for purposes of this paragraph.

(7)	Purchase or sell real estate unless acquired as a result of ownership of securities or other instruments (but this shall not prevent the Master Portfolio from investing in securities or other instruments backed by real estate or securities of companies engaged in the real estate business).

(8)

Purchase or sell commodities, provided that (i) currency will not be deemed to be a commodity for purposes of this restriction, (ii) this restriction does not limit the purchase or sale of futures contracts, forward contracts or options, and (iii) this restriction does not limit the purchase or sale of securities or other instruments backed by commodities or the purchase or sale of commodities acquired as a result of ownership of securities or other instruments.

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Notations Regarding the Master Portfolio's Fundamental Investment Restrictions

The following notations are not considered to be part of the Master Portfolio's fundamental investment restrictions and are subject to change without interestholder approval.

With respect to fundamental investment restriction no. 3 above, the 1940 Act currently allows the Master Portfolio to borrow up to one-third of the value of its total assets (including the amount borrowed) valued at the lesser of cost or market, less liabilities (not including the amount borrowed) at the time the borrowing is made. In addition, the Master Portfolio has received an exemptive order from the SEC permitting it to borrow through the Interfund Lending Program (discussed below), subject to the conditions of the exemptive order. With respect to fundamental investment restriction no. 5 above, the 1940 Act and regulatory interpretations currently limit the percentage of the Master Portfolio's securities that may be loaned to one-third of the value of its total assets.

While certain swaps are now considered commodity interests for purposes of the Commodity Exchange Act and the rules thereunder, at the time of the Master Portfolio's adoption of fundamental investment restriction no. 8 above, many swaps were treated as securities for purposes of the Master Portfolio's compliance with applicable law. Accordingly, fundamental investment restriction no. 8 above is being interpreted to permit the Master Portfolio to engage in transactions in swaps and options on swaps related to financial instruments, such as securities, securities indices and currencies, but not to engage in transactions in swaps or options on swaps related to physical commodities, such as oil or metals.

NON-FUNDAMENTAL INVESTMENT RESTRICTIONS. Under its non-fundamental investment restrictions, which may be changed by vote of a majority of the Trustees of MIP's Board of Trustees (the "Board of Trustees" or the "Board") without interestholder approval, the Master Portfolio may not:

(1)

Purchase securities of other investment companies, except to the extent permitted by the 1940 Act. As a matter of policy, however, the Master Portfolio will not purchase shares of any registered open-end investment company or registered unit investment trust, in reliance on Section 12(d)(1)(F) or (G) (the "fund of funds" provisions) of the 1940 Act, at any time the Master Portfolio has knowledge that its shares are purchased by another investment company investor in reliance on the provisions of subparagraph (G) of Section 12(d)(1).

(2)	Make short sales of securities or maintain a short position, except to the extent permitted by the Master Portfolio's Prospectus and Statement of Additional Information, as amended from time to time, and applicable law.

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ITEM 17.

MANAGEMENT OF THE TRUST.

The following information supplements and should be read in conjunction with Item 10 of Part A.

MIP incorporates by reference the information concerning the management of MIP and the Master Portfolio from the following section of the SAI: "Information on Trustees and Officers." The Board of Trustees has responsibility for the overall management and operations of the Master Portfolio. The Board of Trustees of MIP has the same chair and the same committee structure as the board of trustees of BlackRock Funds III.

COMPENSATION OF TRUSTEES. MIP incorporates by reference the information concerning the compensation of the Trustees of MIP from the following section of the SAI: "Information on Trustees and Officers - Compensation of Trustees ."

CODES OF ETHICS. MIP has the same code of ethics as BlackRock Funds III. MIP incorporates by reference the information concerning the code of ethics from the following section of the SAI: "Management and Other Service Arrangements - Code of Ethics."

PROXY VOTING POLICIES. MIP incorporates by reference to the information concerning its Proxy Voting Policies from the following sections of the SAI: "Proxy Voting Policies and Procedures" and "Appendix B - Proxy Voting Policies ."

INTERESTHOLDER COMMUNICATION TO THE BOARD OF TRUSTEES. The Board of Trustees has established a process for interestholders to communicate with the Board of Trustees. Interestholders may contact the Board of Trustees by mail. Correspondence should be addressed to Master Investment Portfolio Board of Trustees, c/o BlackRock, Inc., 50 Hudson Yards, New York, New York 10001. Interestholder communication to the Board of Trustees should include the following information: (a) the name and address of the interestholder; (b) the percentage interest(s) owned by the interestholder; (c) the Master Portfolios of which the interestholder owns interests; and (d) if these interests are owned indirectly through a broker, financial intermediary or other record owner, the name of the broker, financial intermediary or other record owner. All correspondence received as set forth above shall be reviewed by the Secretary of MIP and reported to the Board of Trustees.

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ITEM 18.

CONTROL PERSONS AND PRINCIPAL HOLDERS OF SECURITIES.

As of April 4, 2024, the interestholders identified below were known by MIP to own 5% or more of the outstanding voting interests of the Master Portfolio in the indicated capacity. Approximate percentages are indicated in the table below.

Master Portfolio		Name and Address of Interestholder		Percentage of Master Portfolio		Nature of Ownership
Diversified Equity Master Portfolio		UTIMCO Active Stock I Master Investment Portfolio 400 Howard Street San Francisco, CA 94105		25%		Beneficial
Diversified Equity Master Portfolio		BlackRock Diversified Equity Fund c/o BlackRock Funds III 400 Howard Street San Francisco, CA 94105		31%		Record
Diversified Equity Master Portfolio		Active Stock LP Feeder1 Master Investment Portfolio 400 Howard Street San Francisco, CA 94105		41%		Record

1	Represents aggregate holdings of the ten LifePath® Dynamic Funds.

For purposes of the 1940 Act, any person who owns directly or through one or more controlled companies more than 25% of the voting securities of a company is presumed to "control" such company. Accordingly, to the extent that an interestholder identified in the foregoing table is identified as the beneficial holder of more than 25% of the Master Portfolio, or is identified as the holder of record of more than 25% of the Master Portfolio and has voting and/or investment powers, such interestholder may be presumed to control the Master Portfolio.

As of April 2, 2024, the Trustees and officers of MIP as a group directly or indirectly beneficially owned an aggregate of less than 1% of the outstanding interests of the Master Portfolio. As of December 31, 2023, none of the Independent Trustees of MIP or their immediate family members owned beneficially or of record any securities of the Master Portfolio's investment adviser, principal underwriter, or any person directly or indirectly controlling, controlled by, or under common control with such entities.

ITEM 19.

INVESTMENT ADVISORY AND OTHER SERVICES.

The following information supplements and should be read in conjunction with Items 10 and 12 in Part A. Information relating to the investment management and other services provided to the Master Portfolio by BlackRock Fund Advisors ("BFA") is incorporated herein by reference from the section entitled "Management of the Funds" in the BlackRock Funds III Feeder Fund's Prospectus and from the sub-section entitled "Management, Advisory and Other Service Arrangements" in Part I of the SAI and the section entitled "Management and Other Service Arrangements" in Part II of the SAI. The following list identifies the specific sections and sub-sections in the BlackRock Funds III Feeder Fund's SAI under which the information required by Item 19 of Form N-1A may be found. Each listed section is incorporated herein by reference.

Form N-1A Item No		Sections Incorporated by Reference from the Prospectus or SAI of BlackRock Diversified Equity Fund
Item 19(a)		SAI: Part I: Management, Advisory and Other Service Arrangements
	SAI: Part II: Management and Other Service Arrangements
Item 19(c)		SAI: Part I: Management, Advisory and Other Service Arrangements
	SAI: Part II: Management and Other Service Arrangements
Item 19(d)		SAI: Part I: Management, Advisory and Other Service Arrangements
	SAI: Part II: Management and Other Service Arrangements
Item 19(e)		Not Applicable
Item 19(f)		Not Applicable
Item 19(g)		Not Applicable
Item 19(h)		Prospectuses: Funds and Service Providers
	SAI: Part I: Management, Advisory and Other Service Arrangements
	SAI: Part II: Management and Other Service Arrangements
Item 19(i)		SAI Part I: Portfolio Transactions and Brokerage - Securities Lending

(b)

Principal Underwriter

BlackRock Investments, LLC ("BRIL"), 50 Hudson Yards, New York, New York 10001, an affiliate of BlackRock, acts as placement agent for each Master Portfolio pursuant to a placement agent agreement (the "Placement Agent Agreement"). Under the Placement Agent Agreement, BRIL receives no compensation for acting as placement agent for the Master Portfolios.

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ITEM 20.

PORTFOLIO MANAGERS.

MIP incorporates by reference the information concerning the portfolio managers for the Master Portfolio from the following section of the SAI: "Management, Advisory and Other Service Arrangements - Information Regarding the Portfolio Managers."

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ITEM 21.

BROKERAGE ALLOCATION AND OTHER PRACTICES.

MIP incorporates by reference the information describing the Master Portfolio's policies governing portfolio securities transactions generally, portfolio turnover, brokerage commissions and frequent trading in portfolio securities from the sections entitled "Portfolio Transactions and Brokerage" in Part I of the SAI and "Portfolio Transactions and Brokerage" in Part II of the SAI.

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ITEM 22.

CAPITAL STOCK AND OTHER INTERESTS.

Pursuant to MIP's Declaration of Trust, the Trustees are authorized to issue beneficial interests in the Master Portfolio. Interestholders in the Master Portfolio are entitled to participate pro rata in distributions and, generally, in allocations of income, gain, loss, deduction and credit of the Master Portfolio. Under certain circumstances, allocations of tax items to interestholders will not be made pro rata in accordance with their interests in the Master Portfolio in order to comply with tax rules and regulations applicable to such allocations. Upon liquidation or dissolution of the Master Portfolio, interestholders are entitled to share pro rata in the Master Portfolio's net assets available for distribution to its interestholders. Interests in the Master Portfolio have no preference, preemptive, conversion or similar rights and are fully paid and non-assessable, except as set forth below. Interests in the Master Portfolio may not be transferred. No certificates are issued. MIP may be terminated at any time by vote of interestholders holding at least a majority of the interests of each series entitled to vote or by the Trustees by written notice to the interestholders. Any series of interests may be terminated at any time by vote of interestholders holding at least a majority of the interests of such series entitled to vote or by the Trustees by written notice to the interestholders of such series.

Each interestholder is entitled to vote, with respect to matters affecting each of MIP's portfolios, in proportion to the amount of its investment in MIP. Interestholders in MIP do not have cumulative voting rights, and interestholders holding more than

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50% of the aggregate beneficial interest in MIP may elect all of the Trustees of MIP if they choose to do so and in such event the other interestholders in MIP would not be able to elect any Trustee. MIP is not required to hold annual meetings of interestholders but MIP may hold special meetings of interestholders when in the judgment of MIP's Trustees it is necessary or desirable to submit matters for interestholders' vote.

Rule 18f-2 under the 1940 Act provides that any matter required to be submitted under the provisions of the 1940 Act or applicable state law or otherwise to the holders of the outstanding voting interests of an investment company that issues two or more classes or series, such as MIP, will not be deemed to have been effectively acted upon unless approved by the holders of a majority of the outstanding interests of each class or series affected by such matter. Rule 18f-2 further provides that a class or series, such as the Master Portfolio, shall be deemed to be affected by a matter unless it is clear that the interests of each class or series in the matter are substantially identical or that the matter does not affect any interest of the class or series. However, Rule 18f-2 exempts the selection of independent accountants and the election of Trustees from the separate voting requirements of Rule 18f-2.

ITEM 23.

PURCHASE, REDEMPTION AND PRICING OF INTERESTS.

The following information supplements and should be read in conjunction with Item 11 in Part A.

PURCHASE OF INTERESTS. Beneficial interests in the Master Portfolio are issued solely in private placement transactions that do not involve any "public offering" within the meaning of Section 4(a)(2) of the 1933 Act. Investments in the Master Portfolio may only be made by investment companies or certain other entities that are "accredited investors" within the meaning of Regulation D under the 1933 Act. This registration statement does not constitute an offer to sell, or the solicitation of an offer to buy, any "security" within the meaning of the 1933 Act.

IN-KIND PURCHASES. Payment for interests of the Master Portfolio may, at the discretion of BFA, be made in the form of securities that are permissible investments for the Master Portfolio and must meet the investment objective, policies and limitations of the Master Portfolio as described in Part A. In connection with an in-kind securities payment, the Master Portfolio may require, among other things, that the securities: (i) be valued on the day of purchase in accordance with the pricing methods used by the Master Portfolio; (ii) be accompanied by satisfactory assurance that the Master Portfolio will have good and marketable title to such securities received by it; (iii) not be subject to any restrictions upon resale by the Master Portfolio; (iv) be in proper form for transfer to the Master Portfolio; and (v) be accompanied by adequate information concerning the basis and other tax matters relating to the securities. All dividends, interest, subscription or other rights pertaining to such securities shall become the property of the Master Portfolio engaged in the in-kind purchase transaction and must be delivered to the Master Portfolio by the investor upon receipt from the issuer. Securities acquired through an in-kind purchase will be acquired for investment and not for immediate resale. Interests purchased in exchange for securities generally cannot be redeemed until the transfer has settled.

SUSPENSION OF REDEMPTIONS. The right of redemption of interests in the Master Portfolio may be suspended or the date of redemption payment postponed as provided in Item 11 in Part A.

VALUATION. MIP incorporates by reference information concerning the Master Portfolio's and MIP's pricing of interests from the following section of the SAI: "Pricing of Shares - Determination of Net Asset Value."

DECLARATION OF TRUST PROVISIONS REGARDING REDEMPTIONS AT OPTION OF TRUST. Pursuant to the Declaration of Trust, MIP shall, subject to applicable law, have the right at its option and at any time to redeem interests of any interestholder at the net asset value thereof as determined in accordance with the Declaration of Trust (i) if at such time such interestholder owns fewer interests than, or interests having an aggregate net asset value of less than, an amount determined from time to time by the Trustees; or (ii) to the extent that such interestholder owns interests of a particular series or class equal to or in excess of a percentage of the outstanding interests of that series or class, or a percentage of the aggregate net asset value of that series or class, determined from time to time by the Trustees; or (iii) to the extent that such interestholder owns interests of MIP equal to or in excess of a percentage of the aggregate outstanding interests of MIP, or a percentage of the aggregate net asset value of MIP, as determined from time to time by the Trustees.

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ITEM 24.

TAXATION OF THE TRUST.

The Master Portfolio has more than one feeder fund and is treated as a non-publicly traded partnership under the Internal Revenue Code. If the Master Portfolio had only one feeder fund (either (i) directly or (ii) indirectly through an entity that is disregarded for U.S. federal income tax purposes), the Master Portfolio's existence as an entity separate from that feeder fund would be disregarded for U.S. federal income tax purposes.

Whether the Master Portfolio is a partnership or disregarded as a separate entity, it will generally not be subject to any U.S. federal income tax. Each of the Master Portfolio's feeder funds will take into account its allocable share of the Master Portfolio's ordinary income, capital gains, losses, deductions and credits in determining its income tax liability and, if the feeder fund is intended to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code, the feeder fund will take into account its allocable share of the Master Portfolio's income and assets for purposes of the feeder fund's gross income and asset diversification tests.

It is intended that the Master Portfolio's assets, income and distributions will be managed in such a way that each feeder fund will be able to satisfy the requirements of Subchapter M of the Internal Revenue Code for qualification as a regulated investment company, assuming that the feeder fund invests all of its investable assets in the Master Portfolio and the feeder fund meets all other requirements for such qualification not within the control of the Master Portfolio.

Certain transactions of the Master Portfolio are subject to special tax rules of the Internal Revenue Code that may, among other considerations, (a) affect the character of gains and losses realized, (b) disallow, suspend or otherwise limit the allowance of certain losses or deductions, and (c) accelerate the recognition of income without a corresponding receipt of cash (with which to make the necessary distributions to satisfy distribution requirements applicable to regulated investment companies). Operation of these rules could, therefore, affect the character, amount and timing of distributions to shareholders of a feeder fund.

Special tax rules also will require certain types of positions to be marked to market (i.e., treated as sold on the last day of the taxable year), which may result in the recognition of income without a corresponding receipt of cash.

If the Master Portfolio purchases shares of an investment company (or similar investment entity) organized under foreign law, each of its feeder funds, by virtue of owning such Master Portfolio's interests, will generally be treated as owning shares in a passive foreign investment company ("PFIC") for U.S. federal income tax purposes. A feeder fund may be subject to U.S. federal income tax (plus an interest charge) on certain distributions from such a PFIC and on gain from the disposition of the shares in such a PFIC (collectively referred to as "excess distributions"). A feeder fund, even if it is a regulated investment company, cannot eliminate this tax by making distributions to its shareholders.

However, an election can be made to mark to market the interest in the PFIC, and thus to take into account the economic gains (and to a limited extent losses) in such investment as though the feeder fund's shares in the PFIC had been sold and repurchased on the last day of the feeder fund's taxable year. Such gain and loss are treated as ordinary income and loss. Alternatively, an election may be made to treat a PFIC as a "qualified electing fund" ("QEF"), in which case a feeder fund will be required to include in its gross income its share of the PFIC's ordinary earnings and net capital gain annually, regardless of whether it receives any distributions from the PFIC. With the mark-to-market or QEF election, a feeder fund could avoid imposition of the interest charge with respect to excess distributions from PFICs, but in any particular year might be required to recognize income in excess of the distributions received from PFICs.

If the Master Portfolio is treated as a partnership for U.S. federal income tax purposes, then, in the event of an audit, the U.S. federal income tax treatment of income and deductions of the Master Portfolio generally will be determined at the Master Portfolio level in a single proceeding (rather than by individual Internal Revenue Service audits of each feeder fund), which the Master Portfolio's partnership representative will control. Any adjustment that results in additional tax (including interest and penalties thereon) will be assessed and collected at the Master Portfolio level in the current taxable year, with each current feeder fund indirectly bearing such cost, unless the Master Portfolio elects to have the partnership adjustment taken into account by each feeder fund that was an investor in the Master Portfolio in the year to which the adjustments relates. If the election is made, each feeder fund will be required to take into account such adjustment and pay tax on such adjustment at the feeder fund level, unless, if the feeder fund is a regulated investment company, it timely distributes the adjustment amount in the form of a "deficiency dividend" (within the meaning of section 860(f) of the Internal Revenue Code), in which case the feeder fund will only have to pay the interest charge imposed on regulated investment companies making a deficiency dividend. The legal and accounting costs incurred in connection with any regular audit of the Master Portfolio's tax returns will be borne by each feeder fund and, indirectly, by their shareholders.

Investors are advised to consult their own tax advisers on the tax consequences of an investment in a feeder fund and the Master Portfolio.

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ITEM 25.

UNDERWRITERS.

The exclusive placement agent for MIP is BRIL, which receives no compensation from the Master Portfolio for serving in this capacity. Registered broker-dealers and investment companies, insurance company separate accounts, common and commingled trust funds, group trusts and similar organizations and entities which constitute accredited investors, as defined in the regulations adopted under the 1933 Act, may continuously invest in the Master Portfolio.

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ITEM 26.

CALCULATION OF PERFORMANCE DATA.

Not applicable.

ITEM 27.

FINANCIAL STATEMENTS.

The audited financial statements and financial highlights, including the schedule of investments, statement of assets and liabilities, statement of operations, statements of changes in net assets, and independent registered public accounting firm's reports for the Master Portfolio for the fiscal year ended December 31, 2023 are included in the Master Portfolio's Form N-CSR (SEC File No. 811-08162) as filed with the SEC on March 6, 2024 and are hereby incorporated by reference. The annual report is available upon request and without charge.

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PART C

OTHER INFORMATION

ITEM 28.

EXHIBITS.

EXHIBIT		DESCRIPTION
1		Articles of Incorporation.
(a)		Certificate of Trust, dated October 20, 1993, is incorporated by reference to Exhibit 1(b) to Amendment No. 7 to the Registrant's Registration Statement on Form N-1A (File No. 811-08162) (the "Registrant's Registration Statement"), filed on August 31, 1998.
(b)		Certificate of Amendment to the Certificate of Trust, dated August 19, 1998, is incorporated by reference to Exhibit 1(d) to Amendment No. 7 to the Registrant's Registration Statement, filed on August 31, 1998.
(c)		Second Amended and Restated Agreement and Declaration of Trust, dated November 17, 2006, is incorporated by reference to Exhibit (a)(1) to Amendment No. 35 to the Registrant's Registration Statement, filed on December 27, 2006.
(d)		Amendment No. 1 to the Second Amended and Restated Agreement and Declaration of Trust, dated December 11, 2007, is incorporated by reference to Exhibit (a)(4) to Amendment No. 39 to the Registrant's Registration Statement, filed on December 2, 2009.
(e)		Amendment No. 2 to the Second Amended and Restated Agreement and Declaration of Trust, dated November 13, 2009, is incorporated by reference to Exhibit (a)(5) to Amendment No. 40 to the Registrant's Registration Statement, filed on April 30, 2010.
2		By-laws.
(a)		Amended and Restated By-Laws, dated November 29, 2018, are incorporated by reference to Exhibit (b)(1) to Amendment No. 112 to the Registrant's Registration Statement, filed on October 30, 2019.
(b)		Amendment No. 1 to the Amended and Restated By-Laws, dated November 11, 2020, is incorporated by reference to Exhibit 2(b) to Amendment No. 120 to the Registrant's Registration Statement, filed on April 30, 2021.
3		Instruments Defining Rights of Security Holders.
(a)		Not applicable.
4		Investment Advisory Contracts.
(a)(1)		Amended Investment Advisory Contract among the Registrant, BlackRock Advisors, LLC ("BAL") and BlackRock Fund Advisors ("BFA"), dated December 28, 2012 (the "Investment Advisory Contract"), is incorporated by reference to Exhibit (d)(1) to Amendment No. 50 to the Registrant's Registration Statement, filed on April 30, 2013.
(a)(2)		Schedule A, amended March 9, 2020, and Schedule B, amended July 1, 2019, to the Investment Advisory Contract are incorporated by reference to Exhibit (d)(2) to Amendment No. 114 to the Registrant's Registration Statement, filed on April 24, 2020.
(b)		Form of Sub-Investment Advisory Agreement between BAL and BFA, with respect to International Tilts Master Portfolio, is incorporated by reference to Exhibit (d)(4) to Amendment No. 58 to the Registrant's Registration Statement, filed on February 26, 2014.
(c)		Form of Amended and Restated Sub-Investment Advisory Agreement between BAL and BlackRock International Limited ("BIL") with respect to International Tilts Master Portfolio is incorporated by reference to Exhibit (d)(4) to Amendment No. 114 to the Registrant's Registration Statement, filed on April 24, 2020.
(d)		Form of Sub-Investment Advisory Agreement between BFA and BIL with respect to Money Market Master Portfolio is incorporated by reference to Exhibit 4(d) to Amendment No. 120 to the Registrant's Registration Statement, filed on April 30, 2021.
5		Underwriting Contracts.
(a)(1)		Form of Placement Agency Agreement between the Registrant and BlackRock Investments, LLC ("BRIL") (the "Placement Agency Agreement") is incorporated by reference to Exhibit (e)(3) to Amendment No. 42 to the Registrant's Registration Statement, filed on March 31, 2011.
(a)(2)		Appendix A to the Placement Agency Agreement, amended March 9, 2020, is incorporated by reference to Exhibit (e)(2) to Amendment No. 114 to the Registrant's Registration Statement, filed on April 24, 2020.

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6		Bonus or Profit Sharing Contracts.
(a)		Not applicable.
7		Custodian Agreements.
(a)		Master Custodian Agreement between the Registrant and State Street Bank and Trust Company ("State Street"), dated December 31, 2018, is incorporated by reference to Exhibit 7(g) to Post-Effective Amendment No. 943 to the Registration Statement on Form N-1A of BlackRock FundsSM (File No. 33-26305), filed on February 28, 2019.
8		Other Material Contracts.
(a)(1)		Form of Administration Agreement between BAL and the Registrant on behalf of Money Market Master Portfolio and Treasury Money Market Master Portfolio (the "Money Market Master Portfolios"), S&P 500 Index Master Portfolio, U.S. Total Bond Index Master Portfolio, Diversified Equity Master Portfolio (f/k/a Active Stock Master Portfolio) and International Tilts Master Portfolio (the "Unitary Administration Agreement") is incorporated by reference to Exhibit (h)(1) to Amendment No. 50 to the Registrant's Registration Statement, filed on April 30, 2013.
(a)(2)		Appendix A to the Unitary Administration Agreement, amended March 9, 2020, is incorporated by reference to Exhibit (h)(2) to Amendment No. 114 to the Registrant's Registration Statement, filed on April 24, 2020.
(b)(1)		Form of Administration Agreement between BAL and the Registrant on behalf of Total International ex U.S. Index Master Portfolio and Large Cap Index Master Portfolio (the "Non-Unitary Administration Agreement") is incorporated by reference to Exhibit (h)(2) to Amendment No. 50 to the Registrant's Registration Statement, filed on April 30, 2013.
(b)(2)		Exhibit A to the Non-Unitary Administration Agreement, amended March 2, 2020, is incorporated by reference to Exhibit (h)(4) to Amendment No. 114 to the Registrant's Registration Statement, filed on April 24, 2020.
(c)		Form of Eighth Amended and Restated Securities Lending Agency Agreement between Registrant and BlackRock Institutional Trust Company, N.A. is incorporated by reference to Exhibit 8(d) of Post-Effective Amendment No. 70 to the Registration Statement on Form N-1A of BlackRock ETF Trust (File No. 333-228832), filed on March 21, 2024.
(d)		Form of Transfer Agency and Service Agreement between the Registrant and State Street with respect to the Money Market Master Portfolios is incorporated by reference to Exhibit 8(b) to Post-Effective Amendment No. 289 to the Registration Statement on Form N-1A of BlackRock Funds III (File No. 33-54126), filed on April 29, 2019.
(e)		Form of Eleventh Amended and Restated Credit Agreement among Registrant, a syndicate of banks and certain other parties is incorporated herein by reference to Exhibit (h)(5) of Post-Effective Amendment No. 9 to the Registration Statement on Form N-1A of BlackRock Series Fund II, Inc. (File No. 333-224375), filed on April 19, 2024.
(f)		Administration and Fund Accounting Services Agreement between the Registrant and State Street, dated December 31, 2018, is incorporated by reference to Exhibit 8(k) to Post-Effective Amendment No. 43 to the Registration Statement on Form N-1A of Managed Account Series (File No. 333-124463), filed on February 28, 2019.
(g)		Form of Thirteenth Amended and Restated Expense Limitation Agreement by and between Registrant, BlackRock Advisors, LLC and BlackRock Fund Advisors is incorporated by reference to Exhibit 8(e) of Post-Effective Amendment No. 70 to the Registration Statement on Form N-1A of BlackRock ETF Trust (File No. 333-228832), filed on March 21, 2024.
(h)		BlackRock Rule 12d1-4 Fund of Funds Investment Agreement between the Registrant and the other registered open-end investment companies party thereto is incorporated herein by reference to Exhibit 8(g) of Post-Effective Amendment No. 37 to the Registration Statement on Form N-1A of BlackRock Unconstrained Equity Fund (File No. 333-124372), filed on August 22, 2023.
9		Legal Opinion.
(a)		Consent of Counsel (Sidley Austin LLP) is incorporated by reference to Exhibit (i) to Amendment No. 40 to the Registrant's Registration Statement, filed on April 30, 2010.
10		Other Opinions.
(a)		None.
11		Omitted Financial Statements.
(a)		Not applicable.

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12		Initial Capital Agreements.
(a)		Not applicable.
13		Rule 12b-1 Plan.
(a)		Not applicable.
14		Rule 18f-3 Plan.
(a)		Not applicable.
15		Reserved.
16		Code of Ethics.
(a)		Code of Ethics of Registrant, BlackRock Investments, LLC, BlackRock Advisors, LLC, BlackRock Fund Advisors and BlackRock International Limited is incorporated by reference to Exhibit 16(a) of Post-Effective Amendment No. 1204 to the Registration Statement on Form N-1A of BlackRock FundsSM (File No. 33-26305), filed on January 24, 2024.

ITEM 29.

PERSONS CONTROLLED BY OR UNDER COMMON CONTROL WITH REGISTRANT.

The Registrant does not control and is not under common control with any other person.

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ITEM 30.

INDEMNIFICATION.

Section 1 of Article IX of the Registrant's Second Amended and Restated Agreement and Declaration of Trust states:

"(a) Subject to the exceptions and limitations contained in paragraph (b) below: (i) every Person who is, or has been, a Trustee or officer of the Trust (including any individual who serves at its request as director, officer, partner, trustee or the like of another organization in which it has any interest as a shareholder, creditor or otherwise) (hereinafter referred to as a "Covered Person") shall be indemnified by the Trust, or by one or more Series thereof if the claim arises from his or her conduct with respect to only such Series (unless the Series was terminated prior to any such liability or claim being known to the Trustees, in which case such obligations, to the extent not satisfied out of the assets of a Series, the obligation shall be an obligation of the Trust), to the fullest extent permitted by law against liability and against all expenses reasonably incurred or paid by such Covered Person in connection with any claim, action, suit, or proceeding in which such Covered Person becomes involved as a party or otherwise or is threatened to be involved as a party or otherwise by virtue of being or having been a Trustee or officer and against amounts paid or incurred by such Covered Person in the settlement thereof; and (ii) the words "claim," "action," "suit," or "proceeding" shall apply to all claims, actions, suits, or proceedings (civil, criminal, regulatory or other, including investigations and appeals), actual or threatened, while in office or thereafter, and the words "liability" and "expenses" shall include, without limitation, attorney's fees, costs, judgments, amounts paid in settlement, fines, penalties, and other liabilities.

(b) No indemnification shall be provided hereunder to a Covered Person: (i) who shall have been adjudicated by a court or body before which the proceeding was brought (A) to be liable to the Trust or its Interestholders by reason of willful misfeasance, bad faith, gross negligence, or reckless disregard of the duties involved in the conduct of the Covered Person's office or (B) not to have acted in good faith in the reasonable belief that his or her action was in the best interest of the Trust; or (ii) in the event of a settlement or other disposition not involving a final adjudication as provided in paragraph (b)(i) resulting in a payment by a Covered Person, unless there has been a determination that such Trustee or officer did not engage in willful misfeasance, bad faith, gross negligence, or reckless disregard of the duties involved in the conduct of his or her office: (A) by the court or other body approving the settlement or other disposition; (B) by at least a majority of those Trustees who neither are Interested Persons of the Trust nor are parties to the matter based upon a review of readily-available facts (as opposed to a full trial-type inquiry); or (C) by written opinion of independent legal counsel based upon a review of readily-available facts (as opposed to a full trial-type inquiry).

(c) The rights of indemnification herein provided may be insured against by policies maintained by the Trust, shall be severable, shall not be exclusive of or affect any other rights to which any Covered Person may now or hereafter be entitled, shall continue as to a person who has ceased to be a Covered Person and shall inure to the benefit of the heirs, executors, and administrators of such a Covered Person. Nothing contained herein shall affect any rights to indemnification to which Trust personnel, other than Covered Persons, and other persons may be entitled by contract or otherwise under law.

(d) To the maximum extent permitted by applicable law, expenses in connection with the preparation and presentation of a defense to any claim, action, suit, or proceeding of the character described in paragraph (a) of this Article IX, Section 1 may be paid by the Trust or Series from time to time prior to final disposition thereof upon receipt of an undertaking by or on behalf of such Covered Person that such amount will be repaid by such Covered Person to the Trust or Series if it ultimately is determined that he or she is not entitled to indemnification under this Article IX, Section 1; provided, however, that either (i) such Covered Person shall have provided a surety bond or some other appropriate security for such undertaking; (ii) the Trust or Series thereof is insured against losses arising out of any such advance payments, or (iii) either a majority of the Trustees who are neither Interested Persons of the Trust nor parties to the matter, or independent legal counsel in a written opinion, shall have determined, based upon a review of readily-available facts (as opposed to a trial-type inquiry or full investigation), that there is a reason to believe that such Covered Person will be entitled to indemnification under this Article IX, Section 1. In connection with any determination pursuant to clause (iii) of the preceding sentence, any Covered Person who is a Trustee and is not an Interested Person of the Trust and any Covered Person who has been a Trustee and at such time was not an Interested Person of the Trust shall be entitled to a rebuttable presumption that he or she has not engaged in willful misfeasance, bad faith, gross negligence, or reckless disregard of the duties involved in the conduct of his or her office.

(e) Any repeal or modification of this Article IX, Section 1, or adoption or modification of any other provision of this Declaration or the By-Laws inconsistent with this Section, shall be prospective only, to the extent that such repeal, or modification adoption would, if applied retrospectively, adversely affect any limitation on the liability of any Covered Person or indemnification available to any Covered Person with respect to any act or omission which occurred prior to such repeal, adoption or modification."

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ITEM 31.

BUSINESS AND OTHER CONNECTIONS OF INVESTMENT ADVISERS.

(a) BlackRock Fund Advisors (previously defined as "BFA") is an indirect wholly-owned subsidiary of BlackRock, Inc. located at 400 Howard Street, San Francisco, California 94105. BFA's business is that of a registered investment adviser to certain open-end, management investment companies and various other institutional investors. The information required by this Item 31 about officers and directors of BFA, together with information as to any other business, profession, vocation or employment of a substantial nature engaged in by such officers and directors during the past two years, is incorporated by reference to Schedules A and D of Form ADV, filed by BFA pursuant to the Investment Advisers Act of 1940, as amended (File No. 801-22609).

(b) BlackRock Advisors, LLC (previously defined as "BAL") is an indirect wholly-owned subsidiary of BlackRock, Inc. located at 100 Bellevue Parkway, Wilmington, Delaware 19809. BAL was organized in 1994 for the purpose of providing advisory services to investment companies. The information required by this Item 31 about officers and directors of BAL, together with information as to any other business, profession, vocation or employment of a substantial nature engaged in by such officers and directors during the past two years, is incorporated by reference to Schedules A and D of Form ADV, filed by BAL pursuant to the Investment Advisers Act of 1940 (SEC File No. 801-47710).

(c) BlackRock International Limited (previously defined as "BIL") is located at Exchange Place One, 1 Semple Street, Edinburgh, EH3 8BL, United Kingdom. The information required by this Item 31 about officers and directors of BIL, together with information as to any other business, profession, vocation or employment of a substantial nature engaged in by such officers and directors during the past two years, is incorporated by reference to Schedules A and D of Form ADV, filed by BIL pursuant to the Investment Advisers Act of 1940 (SEC File No. 801-51087).

ITEM 32.

PRINCIPAL UNDERWRITER.

(a) BlackRock Investments, LLC (previously defined as "BRIL"), the placement agent of the Master Portfolios, acts as the principal underwriter or placement agent, as applicable, for each of the following open-end registered investment companies:

BlackRock Advantage Global Fund, Inc. BlackRock Advantage SMID Cap Fund, Inc. BlackRock Allocation Target Shares BlackRock Bond Fund, Inc. BlackRock California Municipal Series Trust BlackRock Capital Appreciation Fund, Inc. BlackRock Emerging Markets Fund, Inc. BlackRock Equity Dividend Fund BlackRock ETF Trust BlackRock ETF Trust II BlackRock EuroFund BlackRock Financial Institutions Series Trust BlackRock FundSM BlackRock Funds II BlackRock Funds III BlackRock Funds IV BlackRock Funds V BlackRock Funds VI BlackRock Funds VII, Inc. BlackRock Global Allocation Fund, Inc. BlackRock Index Funds, Inc. BlackRock Large Cap Focus Growth Fund, Inc. BlackRock Large Cap Focus Value Fund, Inc. BlackRock Large Cap Series Funds, Inc.		BlackRock Liquidity Funds BlackRock Mid-Cap Value Series, Inc. BlackRock Multi-State Municipal Series Trust BlackRock Municipal Bond Fund, Inc. BlackRock Municipal Series Trust BlackRock Natural Resources Trust BlackRock Series Fund, Inc. BlackRock Series Fund II, Inc. BlackRock Series, Inc. BlackRock Strategic Global Bond Fund, Inc. BlackRock Sustainable Balanced Fund, Inc. BlackRock Unconstrained Equity Fund BlackRock Variable Series Funds, Inc. BlackRock Variable Series Funds II, Inc. iShares, Inc. iShares Trust iShares U.S. ETF Trust Managed Account Series Managed Account Series II Master Bond LLC Master Investment Portfolio Master Investment Portfolio II Quantitative Master Series LLC

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BRIL also acts as the distributor or placement agent for the following closed-end registered investment companies:

BlackRock Alpha Strategies Fund

BlackRock Core Bond Trust

BlackRock Corporate High Yield Fund, Inc.

BlackRock Credit Strategies Fund

BlackRock Debt Strategies Fund, Inc.

BlackRock Enhanced Equity Dividend Trust

BlackRock Floating Rate Income Trust

BlackRock Health Sciences Trust

BlackRock Income Trust, Inc.

BlackRock Investment Quality Municipal Trust, Inc.

BlackRock Limited Duration Income Trust

BlackRock Multi-Sector Income Trust

BlackRock MuniAssets Fund, Inc.

BlackRock Municipal Income Trust

BlackRock Municipal Income Trust II

BlackRock Private Investments Fund

BlackRock Science and Technology Trust

BlackRock Taxable Municipal Bond Trust

BlackRock Utilities, Infrastructure & Power Opportunities Trust 

BRIL provides numerous financial services to BlackRock-advised funds and is the distributor of BlackRock's open-end funds. These services include coordinating and executing Authorized Participation Agreements, preparing, reviewing and providing advice with respect to all sales literature and responding to Financial Industry Regulatory Authority comments on marketing materials.

(b) Set forth below is information concerning each director and officer of BRIL. The principal business address for each such person is 50 Hudson Yards, New York, New York 10001.

Name		Position(s) and Office(s) with BRIL		Position(s) and Office(s) with Registrant
Christopher Meade		Chief Legal Officer, General Counsel and Senior Managing Director		None
Lauren Bradley		Chief Financial Officer and Vice President		None
Gregory Rosta		Chief Compliance Officer and Director		None
Jon Maro		Chief Executive Officer and Director		None
Cynthia Rzomp		Chief Operating Officer		None
Andrew Dickson		Secretary and Managing Director		None
Terri Slane		Assistant Secretary and Director		None
Anne Ackerley		Member, Board of Managers, and Managing Director		None
Michael Bishopp		Managing Director		None
Samara Cohen		Managing Director		None
Jonathan Diorio		Managing Director		None
Lisa Hill		Managing Director		None
Brendan Kyne		Managing Director		None
Martin Small		Member, Board of Managers, and Managing Director		None
Jonathan Steel		Managing Director		None
Ariana Brown		Director		None
Chris Nugent		Director		None
Lourdes Sanchez		Vice President		None
Lisa Belle		Anti-Money Laundering Officer		Anti-Money Laundering Compliance Officer
Gerald Pucci		Member, Board of Managers		None
Philip Vasan		Member, Board of Managers		None

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(c) Not applicable.

ITEM 33.

LOCATION OF ACCOUNTS AND RECORDS.

Omitted pursuant to Instruction 3 of Item 33 of Form N-1A.

ITEM 34.

MANAGEMENT SERVICES.

Other than as set forth under the captions "Item 10. Management, Organization and Capital Structure" in Part A of this Registration Statement, and "Item 17. Management of the Trust" and "Item 19. Investment Advisory and Other Services" in Part B of this Registration Statement, the Registrant is not a party to any management-related service contract.

ITEM 35.

UNDERTAKINGS.

Not applicable.

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SIGNATURES

Pursuant to the requirements of the Investment Company Act of 1940, the Registrant certifies that it has duly caused this Amendment to its Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of New York and the State of New York, on April 29, 2024.

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