Summary Prospectus by Investment Company - Form 497K

Maximum Sales Charge (Load) Imposed on Purchases

(as a percentage of offering price)

Maximum Deferred Sales Charge (Load)

(as a percentage of original purchase price or redemption proceeds, whichever is lower)

Exchange Fee

Management Fees(a)

Other Expenses

Total Annual Fund Operating Expenses(b)

The Fund does not pay an advisory fee to AllianceBernstein L.P. (the "Adviser") under the advisory agreement between AB Corporate Shares, on behalf of the Fund, and the Adviser (the "Advisory Agreement"). Shares of the Fund are available only to (i) investors with accounts established under a wrap fee program or other similar fee-based investment program sponsored and maintained by a registered investment adviser or broker-dealer and for which the Adviser is providing advisory and administrative and other similar services for compensation and (ii) institutional advisory clients of the Adviser. Such investors pay a wrap fee, advisory fee or other fee that covers advisory and administrative and other similar services, which fee is paid at the wrap fee program or fee-based account level. Participants in a wrap fee program or other similar fee-based investment program should review the program brochure or literature provided by the sponsor for a discussion of fees and expenses charged.

Under the Advisory Agreement, the Adviser is contractually responsible for and assumes the obligation for payment of the Fund's expenses included as "Other Expenses" of the Fund, except certain extraordinary expenses, taxes, brokerage fees and commissions and the costs of borrowing money and other leveraging methods, including interest expenses. This obligation will continue in effect for so long as the Adviser serves as the investment adviser to the Fund pursuant to the Advisory Agreement.

After 1 Year

After 3 Years

After 5 Years

After 10 Years

The Examples do not include any fees paid at the wrap fee program or fee-based account level.

tender option bond transactions ("TOBs");

forward commitments;

zero-coupon municipal securities and variable, floating and inverse floating-rate municipal securities;

certain types of mortgage-related securities; and

derivatives, such as options, futures contracts, forwards and swaps.

Market Risk: The value of the Fund's assets will fluctuate as the market or markets in which the Fund invests fluctuate. The value of the Fund's investments may decline, sometimes rapidly and unpredictably, simply because of economic changes or other events, including public health crises (including the occurrence of a contagious disease or illness) and regional and global conflicts, that affect large portions of the market.

ESG Risk: Applying ESG and sustainability criteria to the investment process may exclude securities of certain issuers for non-investment reasons and, therefore, the Fund may forgo some market opportunities available to funds that do not use ESG or sustainability criteria. Securities selected based on ESG factors may shift into and out of favor depending on market and

economic conditions, and the Fund's performance may at times be better or worse than the performance of funds that do not use ESG or sustainability criteria. Furthermore, ESG and sustainability criteria are not uniformly defined, and the Fund's ESG and sustainability criteria may differ from those used by other funds. In addition, in evaluating an investment, the Adviser is dependent upon information and data that may be incomplete, inaccurate or unavailable, which could adversely affect the analysis of the ESG and sustainability factors relevant to a particular investment.

Credit Risk: An issuer or guarantor of a fixed-income security, or the counterparty to a derivatives or other contract, may be unable or unwilling to make timely payments of interest or principal, or to otherwise honor its obligations. The issuer or guarantor may default, causing a loss of the full principal amount of a security and any accrued interest. The degree of risk for a particular security may be reflected in its credit rating. There is the possibility that the credit rating of a fixed-income security may be downgraded after purchase, which may adversely affect the value of the security. Investments in fixed-income securities with lower ratings tend to have a higher probability that an issuer will default or fail to meet its payment obligations.

Municipal Market Risk: This is the risk that special factors may adversely affect the value of municipal securities and have a significant effect on the yield or value of the Fund's investments in municipal securities. These factors include economic conditions, political or legislative changes, public health crises, uncertainties related to the tax status of municipal securities, and the rights of investors in these securities. To the extent that the Fund invests more of its assets in a particular state's municipal securities, the Fund may be vulnerable to events adversely affecting that state, including economic, political and regulatory occurrences, court decisions, terrorism, public health crises (including the occurrence of a contagious disease or illness) and catastrophic natural disasters, such as hurricanes, fires or earthquakes. The Fund's investments in certain municipal securities with principal and interest payments that are made from the revenues of a specific project or facility, and not general tax revenues, may have increased risks. Factors affecting the project or facility, such as local business or economic conditions, could have a significant effect on the project's ability to make payments of principal and interest on these securities.

Tax Risk: There is no guarantee that all of the Fund's income will remain exempt from U.S. federal or state income taxes. From time to time, the U.S. Government and the U.S. Congress consider changes in U.S. federal income tax law that could limit or eliminate the federal tax exemption for municipal bond income, which would in effect reduce the income received by shareholders from the Fund by increasing taxes on that income. In such event, the Fund's net asset value, or NAV, could also decline as yields on municipal bonds, which are typically lower than those on taxable bonds, would be expected to increase to approximately the yield of comparable taxable bonds. Actions or anticipated actions affecting the tax exempt status of municipal bonds could also result in significant shareholder redemptions of Fund shares as investors anticipate adverse effects on the Fund or seek higher yields to offset the potential loss of the tax deduction. As a result, the Fund would be required to maintain higher levels of cash to meet the redemptions, which would negatively affect the Fund's yield. The U.S. federal income tax treatment of payments in respect of certain derivative contracts is unclear.

Below Investment Grade Securities Risk: Investments in fixed-income securities with lower ratings (commonly known as "junk bonds") tend to have a higher probability that an issuer will default or fail to meet its payment obligations. These securities may be subject to greater price volatility due to such factors as specific corporate developments, interest rate sensitivity, negative perceptions of the junk bond market generally and may be more difficult to trade than other types of securities.

Interest Rate Risk: Changes in interest rates will affect the value of investments in fixed-income securities. When interest rates rise, the value of existing investments in fixed-income securities tends to fall and this decrease in value may not be offset by higher income from new investments. Interest rate risk is generally greater for fixed-income securities with longer maturities or durations. The Fund may be subject to a greater risk of rising interest rates than would normally be the case due to the recent end of a period of historically low rates and the effects of potential central bank monetary policy, and government fiscal policy, initiatives and market reactions to those initiatives.

Duration Risk: Duration is a measure that relates the expected price volatility of a fixed-income security to changes in interest rates. The duration of a fixed-income security may be shorter than or equal to full maturity of a fixed-income security. Fixed-income securities with longer durations have more risk and will decrease in price as interest rates rise.

Inflation Risk: This is the risk that the value of assets or income from investments will be less in the future as inflation decreases the value of money. As inflation increases, the value of the Fund's assets can decline as can the value of the Fund's distributions. This risk is significantly greater for fixed-income securities with longer maturities.

Leverage Risk: To the extent the Fund uses leveraging techniques, its NAV may be more volatile because leverage tends to exaggerate the effect of changes in interest rates and any increase or decrease in the value of the Fund's investments.

Illiquid Investments Risk: Illiquid investments risk exists when particular investments, such as lower-rated securities, are or become difficult to purchase or sell, possibly preventing the Fund from selling such investments at an advantageous price. The

Fund is subject to illiquid investments risk because the market for municipal securities is generally smaller than many other markets. Derivatives and securities involving substantial market and credit risk tend to involve greater illiquid investments risk than most other types of investments.

Derivatives Risk: Derivatives may be difficult to price or unwind and leveraged so that small changes may produce disproportionate losses for the Fund. A short position in a derivative instrument involves the risk of a theoretically unlimited increase in the value of the underlying asset, reference rate or index, which could cause the Fund to suffer a potentially unlimited loss. Derivatives, especially over-the-counter derivatives, are also subject to counterparty risk, which is the risk that the counterparty (the party on the other side of the transaction) on a derivative transaction will be unable or unwilling to honor its contractual obligations to the Fund.

Management Risk: The Fund is subject to management risk because it is an actively-managed investment fund. The Adviser will apply its investment techniques and risk analyses in making investment decisions, but there is no guarantee that its techniques will produce the intended results. Some of these techniques may incorporate, or rely upon, quantitative models, but there is no guarantee that these models will generate accurate forecasts, reduce risk or otherwise perform as expected.

how the Fund's performance changed from year to year over the life of the Fund; and

how the Fund's average annual returns for one and five years and since inception compare to those of a broad-based securities market index.

Fund

Return After Taxes on Distributions

Return After Taxes on Distributions and Sales of Fund Shares

Bloomberg U.S. Credit Bond Index

(reflects no deduction for fees, expenses or taxes)

Inception date: 09/12/2017.