# EDGAR Filing Document

**Accession Number:** 0000892538
**File Stem:** 0001193125-26-194845
**Filing Date:** 2026-4
**Character Count:** 19651
**Document Hash:** 8e7cf6453a3a360d0acd8ac65429440c
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-194845.hdr.sgml**: 20260430

**ACCESSION NUMBER**: 0001193125-26-194845

**CONFORMED SUBMISSION TYPE**: 497K

**PUBLIC DOCUMENT COUNT**: 2

**FILED AS OF DATE**: 20260430

**DATE AS OF CHANGE**: 20260430

**EFFECTIVENESS DATE**: 20260430

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** SUNAMERICA SERIES TRUST
- **CENTRAL INDEX KEY:** 0000892538

**ORGANIZATION NAME:**
- **EIN:** 137002445
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 0131
- **LEGAL ENTITY IDENTIFIER:** 549300E40BQMHI2LOX26

**FILING VALUES:**
- **FORM TYPE:** 497K
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 033-52742
- **FILM NUMBER:** 26920841

**BUSINESS ADDRESS:**
- **STREET 1:** 5300 MEMORIAL DRIVE
- **STREET 2:** SUITE 1150
- **CITY:** HOUSTON
- **STATE:** TX
- **ZIP:** 77007
- **BUSINESS PHONE:** 551-235-3560

**MAIL ADDRESS:**
- **STREET 1:** ONE WORLD TRADE CENTER, SUITE J
- **STREET 2:** 49TH FL
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10007

## Series and Classes Contracts Data

### SA PineBridge High-Yield Bond Portfolio (Series ID: S000008101)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000022026 | Class 1      |  |
| C000022027 | Class 2      |  |
| C000022028 | Class 3      |  |

**Summary Prospectus**

**May 1, 2026**

**SunAmerica Series Trust**

**SA PineBridge High-Yield Bond Portfolio**

**(Class 1, Class 2 and Class 3 Shares)**

SunAmerica Series Trust's [Statutory Prospectus and Statement of Additional Information](https://www.sec.gov/ix?doc=/Archives/edgar/data/0000892538/000119312526182445/d67063d485bpos.htm), each dated May 1, 2026, as amended and supplemented from time to time, and the [most recent shareholder reports](https://www.sec.gov/ix?doc=/Archives/edgar/data/0000892538/000119312526150593/8de95b0a53ad87c.htm) are incorporated into and made part of this Summary Prospectus by reference. The Portfolio is offered only to the separate accounts of certain life insurance companies and to other mutual funds. This Summary Prospectus is not intended for use by other investors.

Before you invest, you may want to review SunAmerica Series Trust's Statutory Prospectus, which contains more information about the Portfolio and its risks. You can find the Statutory Prospectus and the above-incorporated information online at https://venerable.onlineprospectus.net/funds/sast_sst/. You can also get this information at no cost by calling (800) 445-7862 or by sending an e-mail request to fundprospectus@corebridgefinancial.com.

The Securities and Exchange Commission has not approved or disapproved these securities, nor has it determined that this Summary Prospectus is accurate or complete. It is a criminal offense to state otherwise.

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**Investment Goal**

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The Portfolio's investment goals are high current income and, secondarily, capital appreciation.

**Fees and Expenses of the Portfolio**

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This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Portfolio. **The table and the example below do not reflect the separate account fees charged in the variable annuity or variable life insurance policy ("Variable Contracts") in which the Portfolio is offered.** If separate account fees were shown, the Portfolio's annual operating expenses would be higher. Please see your Variable Contract prospectus for more details on the separate account fees.

**<u>Annual Portfolio Operating Expenses</u>** (expenses that you pay each year as a percentage of the value of your investment)

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| | | | |
|:---|:---|:---|:---|
|  | **Class 1** | **Class 2** | **Class 3** |
| Management Fees | 0.64% | &nbsp;&nbsp; 0.64% | &nbsp;&nbsp; 0.64% |
| Service (12b-1) Fees |  | &nbsp;&nbsp; 0.15% | &nbsp;&nbsp; 0.25% |
| Other Expenses | 0.12% | &nbsp;&nbsp; 0.12% | &nbsp;&nbsp; 0.12% |
| &nbsp;&nbsp;&nbsp; Total Annual Portfolio <br> Operating Expenses<br>| 0.76% | &nbsp;&nbsp; 0.91% | &nbsp;&nbsp; 1.01% |

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***<u>Expense Example</u>***

This Example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem or hold all of your shares at the end of those periods. The Example also assumes that your investment

has a 5% return each year and that the Portfolio's operating expenses remain the same (except that the Example incorporates any applicable fee waiver and/or expense limitation arrangements for only the first year). The Example does not reflect charges imposed by the Variable Contract. If the separate account fees were reflected, the expenses would be higher. See the Variable Contract prospectus for information on such charges. Although your actual costs may be higher or lower, based on these assumptions and the net expenses shown in the fee table, your costs would be:

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| | | | | |
|:---|:---|:---|:---|:---|
|  | **1 Year** | **3 Years** | **5 Years** | **10 Years** |
| Class 1 | $78 | &nbsp;&nbsp; $243 | &nbsp;&nbsp; $422 | &nbsp;&nbsp; $942 |
| Class 2 | 93 | &nbsp;&nbsp; 290 | &nbsp;&nbsp; 504 | &nbsp;&nbsp; 1120 |
| Class 3 | 103 | &nbsp;&nbsp; 322 | &nbsp;&nbsp; 558 | &nbsp;&nbsp; 1236 |

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***<u>Portfolio Turnover</u>*** 

The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual portfolio operating expenses or in the Example, affect the Portfolio's performance.

During the most recent fiscal year, the Portfolio's portfolio turnover rate was 48% of the average value of its portfolio.

**Principal Investment Strategies of the Portfolio**

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The Portfolio attempts to achieve its goal by investing, under normal circumstances, at least 80% of its net assets in intermediate and long-term corporate obligations, emphasizing high-yield, high-risk fixed

SunAmerica Series Trust

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**SA PineBridge High-Yield Bond Portfolio**

income securities (junk bonds) with a primary focus on "B" rated high-yield securities.

In addition to junk bonds, the Portfolio may invest in other fixed income securities, primarily loans, convertible bonds, preferred stocks and zero coupon and deferred interest bonds. To a lesser extent, the Portfolio also may invest in U.S. government securities, investment grade bonds and pay-in-kind bonds. The Portfolio may invest in foreign securities and may make short-term investments.

The Portfolio may engage in frequent trading of portfolio securities to achieve its investment goal.

**Principal Risks of Investing in the Portfolio**

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As with any mutual fund, there can be no assurance that the Portfolio's investment goal will be met or that the net return on an investment in the Portfolio will exceed what could have been obtained through other investment or savings vehicles. Shares of the Portfolio are not bank deposits and are not guaranteed or insured by any bank, government entity or the Federal Deposit Insurance Corporation. If the value of the assets of the Portfolio goes down, you could lose money.

The following is a summary of the principal risks of investing in the Portfolio.

**Bonds Risk.** The value of your investment in the Portfolio may go up or down in response to changes in interest rates or defaults (or even the potential for future defaults) by bond issuers. Fixed income securities may be subject to volatility due to changes in interest rates.

**Junk Bonds Risk.** The Portfolio may invest significantly in junk bonds, which are considered speculative. Junk bonds carry a substantial risk of default or changes in the issuer's creditworthiness, or they may already be in default at the time of purchase.

**Interest Rate Risk.** Fixed income securities may be subject to volatility due to changes in interest rates. The value of fixed-income securities may decline when interest rates go up or increase when interest rates go down. The interest earned on fixed-income securities may decline when interest rates go down or increase when interest rates go up. Duration is a measure of interest rate risk that indicates how price-sensitive a bond is to changes in interest rates. Longer-term and lower coupon bonds tend to be more sensitive to changes in interest rates. For example, a bond with a duration of three years will decrease in value by approximately 3% if interest rates increase by 1%. Changing interest rates may have unpredictable effects on markets, may result in

heightened market volatility, and could negatively impact the Portfolio's performance. Any future changes in monetary policy made by central banks and/or their governments are likely to affect the level of interest rates.

**Credit Quality Risk.** An issuer with a lower credit rating will be more likely than a higher rated issuer to default or otherwise become unable to honor its financial obligations. Issuers with low credit ratings typically issue junk bonds. In addition to the risk of default, junk bonds may be more volatile, less liquid, more difficult to value and more susceptible to adverse economic conditions or investor perceptions than other bonds.

**Loan Risk.** Loans are subject to the credit risk of nonpayment of principal or interest. Economic downturns or increases in interest rates may cause an increase in defaults, interest rate risk and illiquidity risk. Loans may or may not be collateralized at the time of acquisition, and any collateral may lack liquidity or lose all or substantially all of its value subsequent to investment. In the event of bankruptcy of a borrower, the Portfolio could experience delays or limitations with respect to its ability to realize the benefits of any collateral securing a loan.

**Foreign Investment Risk.** The Portfolio's investments in the securities of foreign issuers or issuers with significant exposure to foreign markets involve additional risk. Foreign countries in which the Portfolio invests may have markets that are less liquid, less regulated and more volatile than U.S. markets. The value of the Portfolio's investments may decline because of factors affecting the particular issuer as well as foreign markets and issuers generally, such as unfavorable government actions, and political or financial instability and other conditions or events (including, for example, military confrontations, war, terrorism, sanctions, disease/virus, outbreaks and epidemics). Lack of relevant data and reliable public information may also affect the value of these securities.

**U.S. Government Obligations Risk.** U.S. Treasury obligations are backed by the "full faith and credit" of the U.S. Government and generally have negligible credit risk. Securities issued or guaranteed by federal agencies or authorities and U.S. Government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. Government.

**Call Risk.** The risk that an issuer will exercise its right to pay principal on a debt obligation (such as a mortgage-backed security or convertible security) that is held by the Portfolio earlier than expected. This may happen when there is a decline in interest rates. Under these circumstances, the Portfolio may be unable to recoup all

SunAmerica Series Trust

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**SA PineBridge High-Yield Bond Portfolio**

of its initial investment and will also suffer from having to reinvest in lower-yielding securities.

**Active Trading Risk.** The Portfolio may engage in frequent trading of securities to achieve its investment goal. Active trading may result in high portfolio turnover and correspondingly greater brokerage commissions and other transaction costs, which will be borne directly by the Portfolio and could affect its performance. During periods of increased market volatility, active trading may be more pronounced.

**Issuer Risk.** The value of a security may decline for a number of reasons directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer's goods and services.

**Convertible Securities Risk.** The values of the convertible securities in which the Portfolio may invest will be affected by market interest rates, the risk that the issuer may default on interest or principal payments and the value of the underlying common stock into which these securities may be converted. Specifically, certain types of convertible securities may pay fixed interest and dividends; their values may fall if market interest rates rise and rise if market interest rates fall. Additionally, an issuer may have the right to buy back or "call" certain of the convertible securities at a time unfavorable to the Portfolio.

**Preferred Stock Risk.** Preferred stockholders' liquidation rights are subordinate to the company's debt holders and creditors. If interest rates rise, the fixed dividend on preferred stocks may be less attractive and the price of preferred stocks may decline. Deferred dividend payments by an issuer of preferred stock could have adverse tax consequences for the Portfolio and may cause the preferred stock to lose substantial value.

**Management Risk.** The Portfolio is subject to management risk because it is an actively-managed investment portfolio. The Portfolio's portfolio managers apply investment techniques and risk analyses in making investment decisions, but there can be no guarantee that these decisions or the individual securities selected by the portfolio managers will produce the desired results.

**Market Risk.** The Portfolio's share price or the market as a whole can decline for many reasons or be adversely affected by a number of factors, including, without limitation: weakness in the broad market, a particular industry, or specific holdings; adverse social, political, regulatory or economic developments in the United States or abroad; changes in investor psychology; technological disruptions; heavy institutional selling; military confrontations, war, terrorism and other armed conflicts, trade wars and sanctions, disease/virus outbreaks and epidemics; recessions; taxation and international tax treaties; currency, interest rate and price fluctuations; and other conditions or events. In addition, the subadviser's assessment of securities held in the Portfolio may prove incorrect, resulting in losses or poor performance even in a rising market. <br>

**Affiliated Fund Rebalancing Risk.** The Portfolio may be an investment option for other mutual funds for which SunAmerica Asset Management, LLC ("SunAmerica") serves as investment adviser that are managed as "funds of funds." From time to time, the Portfolio may experience relatively large redemptions or investments due to the rebalancing of a fund of funds. In the event of such redemptions or investments, the Portfolio could be required to sell securities or to invest cash at a time when it is not advantageous to do so.

**Performance Information**

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The following bar chart illustrates the risks of investing in the Portfolio by showing changes in the Portfolio's performance from calendar year to calendar year and the table compares the Portfolio's average annual returns to those of the Bloomberg U.S. Universal Bond Index (a broad-based securities market index) and the ICE BofA US High Yield Index, which is relevant to the Portfolio because it has characteristics similar to the Portfolio's investment strategies. Fees and expenses incurred at the contract level are not reflected in the bar chart or table. If these amounts were reflected, returns would be less than those shown. Of course, past performance is not necessarily an indication of how the Portfolio will perform in the future.

SunAmerica Series Trust

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**SA PineBridge High-Yield Bond Portfolio**

**(Class 1 Shares)**

![](g55178highyieldbond_sast1.jpg)

During the period shown in the bar chart:

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| | | |
|:---|:---|:---|
| Highest Quarterly <br> Return:<br>| June 30, 2020 | 9.48% |
| Lowest Quarterly <br> Return:<br>| March 31, 2020 | -11.33% |
| Year to Date Most <br> Recent Quarter:<br>| March 31, 2026 | -0.38% |

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**Average Annual Total Returns** (For the periods ended December 31, 2025)

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| | | | |
|:---|:---|:---|:---|
|  | 1<br> Year<br>| 5<br> Years<br>| 10<br> Years<br>|
| Class 1 Shares | 8.36% | 5.33% | 7.21% |
| Class 2 Shares | 8.19% | 5.15% | 7.03% |
| Class 3 Shares | 8.16% | 5.05% | 6.94% |
| &nbsp;&nbsp;&nbsp;&nbsp; Bloomberg U.S. Universal Bond Index <br> (reflects no deduction for fees, expenses <br> or taxes)<br>| 7.58% | 0.06% | 2.44% |
| &nbsp;&nbsp;&nbsp;&nbsp; ICE BofA US High Yield Index (reflects no <br> deduction for fees, expenses or taxes)<br>| 8.50% | 4.50% | 6.45% |

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**Investment Adviser**

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The Portfolio's investment adviser is SunAmerica.

The Portfolio is subadvised by PineBridge Investments, LLC.

***<u>Portfolio Manager</u>*** 

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| | |
|:---|:---|
| **Name and Title** | **Portfolio**<br> **Manager of the**<br> **Portfolio Since**<br>|
| &nbsp;&nbsp;&nbsp; John Yovanovic, CFA<br> Managing Director and Co-Head of <br> Leveraged Finance Group<br>| 2007 |
| &nbsp;&nbsp;&nbsp; Jeremy Burton, CFA<br> Managing Director and Portfolio <br> Manager<br>| 2021 |

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**Purchases and Sales of Portfolio Shares**

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Shares of the Portfolios may only be purchased or redeemed through Variable Contracts offered by the separate accounts of participating life insurance companies and by other portfolios of the Trust and Seasons Series Trust. Shares of a Portfolio may be purchased and redeemed each day the New York Stock Exchange is open, at the Portfolio's net asset value determined after receipt of a request in good order.

The Portfolios do not have any initial or subsequent investment minimums. However, your insurance company may impose investment or account minimums. Please consult the prospectus (or other offering document) for your Variable Contract which may contain additional information about purchases and redemptions of Portfolio shares.

**Tax Information**

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The Portfolios will not be subject to U.S. federal income tax so long as they qualify as regulated investment companies and distribute their income and gains each year to their shareholders. However, contractholders may be subject to U.S. federal income tax (and a U.S. federal Medicare tax of 3.8% that applies to net investment income, including taxable annuity payments, if applicable) upon withdrawal from a Variable Contract. Contractholders should consult the prospectus (or other offering document) for the Variable Contract for additional information regarding taxation.

**Payments to Broker-Dealers and** <br> **Other Financial Intermediaries**

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The Portfolios are not sold directly to the general public but instead are offered as an underlying investment option for Variable Contracts and to other portfolios of the Trust and Seasons Series Trust. A Portfolio and its related companies may make payments to the sponsoring insurance company (or its affiliates) for distribution and/or other services. These payments may create a conflict of interest as they may be a factor that the insurance company considers in including a Portfolio as an underlying investment option in the Variable Contract. The prospectus (or other offering document) for your Variable Contract may contain additional information about these payments.

CSP-8670_606_507_709.10 (5/26)

SunAmerica Series Trust

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