JNL Series Trust

04/27/2026 | Press release | Distributed by Public on 04/27/2026 06:13

Summary Prospectus by Investment Company (Form 497K)

Summary Prospectus - April 27, 2026

JNL/Fidelity Institutional AM® & JPMorgan Large Cap Growth Fund

(formerly, JNL/ClearBridge Large Cap Growth Fund)

Class A

Class I

Before you invest, you may want to review the Fund's Prospectus, which contains more information about the Fund and its risks. You can find the Fund's Prospectus and other information about the Fund, including the Statement of Additional Information ("SAI") and most recent reports to shareholders, online at https://www.jackson.com/fund-literature.html. You can also get this information at no cost by calling 1-800-644-4565 (Annuity and Life Service Center), 1-800-599-5651 (NY Annuity and Life Service Center), 1-800-777-7779 (for contracts purchased through a bank or financial institution) or 1-888-464-7779 (for NY contracts purchased through a bank or financial institution), or by sending an email request to [email protected]. The current Prospectus and SAI, both dated April 27, 2026, as amended, are incorporated by reference into (which means they legally are a part of) this Summary Prospectus.

Investment Objective. The investment objective of the Fund is to seek long-term capital appreciation.

Expenses. This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund.

The expenses do not reflect the expenses of the variable insurance contracts or the separate account through which you indirectly invest in the Fund, whichever may be applicable, and the total expenses would be higher if they were included.

You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

Shareholder Fees
(fees paid directly from your investment)

Not Applicable

Annual Fund Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
Class A
Management Fee 0.48%
Distribution and/or Service (12b-1) Fees 0.30%
Other Expenses1 0.16%
Total Annual Fund Operating Expenses 0.94%
1 "Other Expenses" include an Administrative Fee of 0.15% which is payable to Jackson National Asset Management, LLC ("JNAM" or "Adviser").
Annual Fund Operating Expenses
(Expenses that you pay each year as a percentage of the value of your investment)
Class I
Management Fee 0.48%
Distribution and/or Service (12b-1) Fees 0.00%
Other Expenses1 0.16%
Total Annual Fund Operating Expenses 0.64%
1 "Other Expenses" include an Administrative Fee of 0.15% which is payable to Jackson National Asset Management, LLC ("JNAM" or "Adviser").

Expense Example. This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. Also, this example does not reflect the expenses of the variable insurance contracts or the separate account through which you indirectly invest in the Fund, whichever may be applicable, and the total expenses would be higher if they were included. The table below shows the expenses you would pay on a $10,000 investment, assuming (1) 5% annual return; (2) redemption at the end of each time period; and (3) that the Fund operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:

JNL/Fidelity Institutional AM® & JPMorgan Large Cap Growth Fund Class A
1 year 3 years 5 years 10 years
$96 $300 $520 $1,155
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JNL/Fidelity Institutional AM® & JPMorgan Large Cap Growth Fund Class I
1 year 3 years 5 years 10 years
$65 $205 $357 $798

Portfolio Turnover (% of average value of portfolio). The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in Annual Fund Operating Expenses or in the Expense Example above, affect the Fund's performance.

Period
1/1/2025 - 12/31/2025 22 %

Portfolio turnover for the period of January 1, 2025 to December 31, 2025 is for the Fund when operating under its former investment strategy.

Principal Investment Strategies. Under normal circumstances, the Fund invests at least 80% of its assets (net assets plus the amount of any borrowings for investment purposes) in equity securities or other equity investments with large market capitalizations. Large-capitalization companies are those companies with market capitalizations similar to companies in the Morningstar US Target Market Exposure Index (the "Index"). The size of the companies in the Index changes with market conditions and the composition of the Index. As of December 31, 2025, the range of such companies in the Index was $11.6 billion to $4.5 trillion. The Fund is classified as a "non-diversified" fund, as defined in the Investment Company Act of 1940, as amended (the "1940 Act"), which means that it may invest more of its assets in fewer issuers than "diversified" mutual funds.

The Fund has flexibility in the relative weighting of each asset class and expects to vary the percentages of assets invested in each asset class from time to time. JNAM's allocations to the underlying Sub-Advisers will be a function of a variety of factors including each underlying strategy's expected returns, volatility, correlation, and contribution to the Fund's overall risk profile.

Two unaffiliated investment managers ("Sub-Advisers") generally provide day to day management for a portion of the Fund's assets (each portion is sometimes referred to as a "sleeve"). Each Sub-Adviser may use different investment strategies in managing Fund assets, acts independently from the others, and uses its own methodology for selecting investments. Jackson National Asset Management, LLC ("JNAM" or "Adviser") is responsible for identifying and retaining the Sub-Advisers for the selected strategies and for monitoring the services provided by the Sub-Advisers. JNAM provides qualitative and quantitative supervision as part of its process for selecting and monitoring the Sub-Advisers. JNAM is also responsible for selecting the Fund's investment strategies and for determining the amount of Fund assets to allocate to each Sub-Adviser. Based on JNAM's ongoing evaluation of the Sub-Advisers, JNAM may adjust allocations among Sub-Advisers.

The Fund may use derivatives, which are instruments that have a value based on another instrument, exchange rate or index, may be used as substitutes for securities in which the Fund can invest. To the extent the Fund uses derivatives, the Fund will primarily use futures contracts to more effectively gain targeted equity exposure from its cash positions. Derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the Fund's 80% policy and are consistent with the Fund's investment policies and limitations with respect to investments in derivatives.

JNAM also may choose to allocate the Fund's assets to additional Sub-Advisers or to replace/remove Sub-Advisers in the future. There is no assurance that any or all of the strategies discussed in this prospectus will be used by JNAM or the Sub-Advisers.

JNAM may also manage Fund assets directly to seek to enhance returns, or to hedge and to manage the Fund's cash and short-term instruments.

Below are the principal investment strategies for each Sub-Adviser's strategy, but the Sub-Advisers may also implement other investment strategies in keeping with their respective strategy's objective.

JPMorgan Strategy

J.P. Morgan Investment Management Inc. ("JPMorgan") that seeks to identify companies with positive price momentum and attractive fundamentals. JPMorgan seeks structural disconnects which allow businesses to exceed market expectations. These disconnects may result from: demographic/cultural changes, technological advancements and/or regulatory changes. JPMorgan's assessment is based on an analysis of key opportunities and risks across industries to seek to identify financially material issues with respect to JPMorgan Strategy's investments in securities and ascertain key issues that merit engagement with issuers. These assessments may not be conclusive and securities of issuers that may be negatively impacted by such factors may be purchased and retained by JPMorgan while the JPMorgan Strategy may divest or not invest in securities of issuers that may be positively impacted by such factors.

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FIAM Strategy

FIAM LLC ("FIAM") constructs the strategy by investing primarily in common stocks of blue chip growth companies that FIAM believes are well-known, well-established and well-capitalized, which generally have large or medium market capitalizations. FIAM invests in "growth companies," which are companies that FIAM believes have above average growth potential.

FIAM considers a number of factors in determining a company's growth potential, such as whether the company is included in a third-party growth benchmark or classified as a growth company by a third-party vendor, if the company's projected earnings per share growth, sales growth per share or free cash flow growth or its trailing earnings per share growth is above the equity market median, if the company's research and development expenses exceed sales, general and administrative expenses, or if the company is raising capital to grow, fund or expand its business. A company's growth potential can be determined under any of these factors.

FIAM uses fundamental analysis of factors such as each issuer's financial condition and industry position, as well as market and economic conditions, to select investments.

FIAM may invest the assets of the FIAM strategy in securities of foreign issuers in addition to securities of domestic issuers.

Principal Risks of Investing in the Fund. An investment in the Fund is not guaranteed. As with any mutual fund, the value of the Fund's shares will change, and you could lose money by investing in the Fund. The principal risks associated with investing in the Fund include:

· Equity securities risk - Common and preferred stocks represent equity ownership in a company. Stock markets are volatile, and equity securities generally have greater price volatility than fixed-income securities. The price of equity or equity-related securities will fluctuate and can decline and reduce the value of a portfolio investing in equity or equity-related securities. The value of equity or equity-related securities purchased or held by the Fund could decline if the financial condition of the companies the Fund invests in decline or if overall market and economic conditions deteriorate. They 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, they 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 interest or currency rates or generally adverse investor sentiment.
· Market risk - Portfolio securities may decline in value due to factors affecting securities markets generally, such as real or perceived adverse economic, political, or regulatory conditions, inflation, changes in interest or currency rates or adverse investor sentiment, public health issues, including widespread disease and virus epidemics or pandemics, war, terrorism or natural disasters, among others. Adverse market conditions may be prolonged and may not have the same impact on all types of securities. The values of securities may fall due to factors affecting a particular issuer, industry or the securities market as a whole.
· Large-capitalization investing risk - Large-capitalization stocks as a group could fall out of favor with the market, which may cause the Fund to underperform funds that focus on other types of stocks.
· Investment style risk - The returns from a certain investment style may be lower than the returns from the overall stock market. Growth stock prices frequently reflect projections of future earnings or revenues, and if earnings growth expectations are not met, their stock prices will likely fall, which may reduce the value of a Fund's investment in those stocks. Over market cycles, different investment styles may sometimes outperform other investment styles (for example, growth investing may outperform value investing).
· Issuer risk - The value of an individual security or particular type of security can be more volatile than the market as a whole and can perform differently from the market as a whole. A security's value may decline for reasons that directly relate to the issuer, such as management performance, corporate governance, financial leverage and reduced demand for the issuer's goods or services.
· Foreign securities risk - Investments in, or exposure to, foreign securities involve risks not typically associated with U.S. investments. These risks include, among others, adverse fluctuations in foreign currency values, possible imposition of foreign withholding or other taxes on income payable on the securities, as well as adverse political, social and economic developments, such as political upheaval, acts of terrorism, financial troubles, sanctions or the threat of new or modified sanctions, or natural disasters. Many foreign securities markets, especially those in emerging market countries, are less stable, smaller, less liquid, and less regulated than U.S. securities markets, and the costs of trading in those markets is often higher than in U.S. securities markets. There may also be less publicly available information about issuers of foreign securities compared to issuers of U.S. securities. In addition, the economies of certain foreign markets may not compare favorably with the economy of the United States with respect to issues such as growth of gross national product, reinvestment of capital, resources and balance of payments position.
· Stock risk - Stock markets may experience significant short-term volatility and may fall sharply at times. Different stock markets may behave differently from each other and U.S. stock markets may move in the opposite direction from one or more foreign stock markets. The prices of individual stocks generally do not all move in the same direction at the same time and a variety of factors can affect the price of a particular company's stock.
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· Information technology sector risk - Information technology companies face intense competition and potentially rapid product obsolescence. They are also heavily dependent on intellectual property rights and may be adversely affected by the loss or impairment of those rights.
· Managed portfolio risk - As an actively managed portfolio, the Fund's portfolio manager(s) make decisions to buy and sell holdings in the Fund's portfolio. Because of this, the value of the Fund's investments could decline because the financial condition of an issuer may change (due to such factors as management performance, reduced demand or overall market changes), financial markets may fluctuate or overall prices may decline, the Sub-Advisers' investment techniques could fail to achieve the Fund's investment objective or negatively affect the Fund's investment performance, or legislative, regulatory, or tax developments may affect the investment techniques available to the Sub-Adviser of the Fund. There is no guarantee that the investment objective of the Fund will be achieved.
· Consumer discretionary risk - If the Fund invests a significant portion of its assets in issuers in the consumer discretionary sector of the market, the Fund may be more affected by events influencing the consumer discretionary sector than a fund that is more diversified across numerous sectors. An investment in issuers in the consumer discretionary sector can be significantly affected by the performance of the overall economy, interest rates, competition and consumer confidence. Success of these companies can depend heavily on disposable household income and consumer spending. Changes in demographics and consumer tastes can also affect the demand for, and success of, products of consumer discretionary companies.
· Sector risk - Companies with similar characteristics may be grouped together in broad categories called sectors. Sector risk is the risk that securities of companies within specific sectors of the economy can perform differently than the overall market. For example, this may be due to changes in the regulatory or competitive environment or changes in investor perceptions regarding a sector. Because the Fund may allocate relatively more assets to certain sectors than others, the Fund's performance may be more susceptible to any developments which affect those sectors emphasized by the Fund. In addition, the Fund could underperform other funds investing in similar sectors or comparable benchmarks because of the investment manager's choice of securities within such sector.
· Derivatives risk - Investments in derivatives, which are financial instruments whose value depends on, or is derived from, the value of underlying assets, reference rates, or indices, can be highly volatile and may be subject to transaction costs and certain risks, such as unanticipated changes in securities prices and global currency investment. Derivatives also are subject to leverage risk, liquidity risk, interest rate risk, market risk, counterparty risk, and credit risk. They also involve the risk of mispricing or improper valuation and the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, interest rate or index. Gains or losses from derivatives can be substantially greater than the derivatives' original cost.
· Non-diversification risk - The Fund is non-diversified, as defined by the 1940 Act, and as such may invest in the securities of a limited number of issuers and may invest a greater percentage of its assets in a particular issuer. Therefore, a decline in the market price of a particular security held by the Fund may affect the Fund's performance more than if the Fund were a diversified investment company.
· Liquidity risk - Investments in securities that are difficult to purchase or sell (illiquid or thinly-traded securities) may reduce returns if the Fund is unable to sell the securities at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk arises, for example, from small average trading volumes, trading restrictions, or temporary suspensions of trading. To meet redemption requests, the Fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions.
· Mid-capitalization investing risk - The stocks of mid-capitalization companies can be more volatile and their shares can be less liquid than those of larger companies. Mid-capitalization companies may have limited product lines, markets or financial resources or may depend on the expertise of a few people and may be subject to more abrupt or erratic market movements than securities of larger, more established companies or the market averages in general. Securities of such issuers may lack sufficient market liquidity to effect sales at an advantageous time or without a substantial drop in price.


Performance. The performance information shown provides some indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual returns compared with those of a broad-based securities market index and an additional index that the Adviser believes more closely reflects the market segments in which the Fund invests. Performance results include the effect of expense waiver/reduction arrangements for some or all of the periods shown. If such arrangements had not been in place, performance for those periods would have been lower. Performance prior to April 27, 2026 reflects the Fund's results when managed by the former sub-adviser, ClearBridge Investments, LLC. The Fund's past performance is not necessarily an indication of how the Fund will perform in the future.

The returns shown in the bar chart and table do not include charges that will be imposed by variable insurance products. If these amounts were reflected, returns would be less than those shown.

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Annual Total Returns as of December 31

Class A

Best Quarter (ended 6/30/2020): 25.93%; Worst Quarter (ended 6/30/2022): -22.71%

Annual Total Returns as of December 31

Class I

Best Quarter (ended 6/30/2020): 25.90%; Worst Quarter (ended 6/30/2022): -22.66%

Average Annual Total Returns as of 12/31/2025
1 year 5 year Life of Fund (September 25, 2017)
JNL/Fidelity Institutional AM® & JPMorgan Large Cap Growth Fund (Class A) 9.05 % 10.46 % 14.48 %
Morningstar US Target Market Exposure Index (reflects no deduction for fees, expenses, or taxes) 17.80 % 13.88 % 14.76 %
Morningstar US Large-Mid Cap Broad Growth Index (reflects no deduction for fees, expenses, or taxes) 16.67 % 13.44 % 17.09 %
Average Annual Total Returns as of 12/31/2025
1 year 5 year Life of Class (September 25, 2017)
JNL/Fidelity Institutional AM® & JPMorgan Large Cap Growth Fund (Class I) 9.39 % 10.79 % 14.82 %
Morningstar US Target Market Exposure Index (reflects no deduction for fees, expenses, or taxes) 17.80 % 13.88 % 14.76 %
Morningstar US Large-Mid Cap Broad Growth Index (reflects no deduction for fees, expenses, or taxes) 16.67 % 13.44 % 17.09 %
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Portfolio Management.

Investment Adviser to the Fund:
Jackson National Asset Management, LLC ("JNAM")

Sub-Advisers:
FIAM LLC ("FIAM")
J.P. Morgan Investment Management Inc. ("JPMorgan")

Portfolio Managers:

Name: Joined Fund Management Team In: Title:
William Harding, CFA April 2026 Senior Vice President, Chief Investment Officer and Portfolio Manager, JNAM
Sean Hynes, CFA, CAIA April 2026 Vice President and Portfolio Manager, JNAM
Mark Pliska, CFA April 2026 Vice President and Portfolio Manager, JNAM
Kyle Ottwell, CFA, CAIA April 2026 Director and Portfolio Manager, JNAM
Sonu Kalra April 2026 Portfolio Manager, FIAM
Adam Benjamin April 2026 Portfolio Manager, FIAM
Giri Devulapally April 2026 Managing Director, JPMorgan
Holly Morris April 2026 Managing Director, JPMorgan
Larry Lee April 2026 Managing Director, JPMorgan
Joseph Wilson April 2026 Managing Director, JPMorgan
Robert Maloney April 2026 Executive Director, JPMorgan

Purchase and Redemption of Fund Shares

Only separate accounts of Jackson National Life Insurance Company ("Jackson National") or Jackson National Life Insurance Company of New York ("Jackson National NY") and series, including fund of funds, of registered investment companies in which either or both of those insurance companies invest may purchase shares of the Fund. You may invest indirectly in the Fund through your purchase of a variable annuity or life insurance contract issued by a separate account of Jackson National or Jackson National NY that invests directly, or through a fund of funds, in this Fund. Any minimum initial or subsequent investment requirements and redemption procedures are governed by the applicable separate account through which you invest indirectly.

This Fund serves as an underlying investment by insurance companies, affiliated investment companies, and retirement plans for funding variable annuity and life insurance contracts and retirement plans.

Tax Information

The Fund expects to be treated as a partnership for U.S. federal income tax purposes, and does not expect to make regular distributions (other than in redemption of Fund shares) to shareholders, which generally are the participating insurance companies investing in the Fund through separate accounts of Jackson National or Jackson National NY and mutual funds owned directly or indirectly by such separate accounts. You should consult the prospectus of the appropriate separate account or description of the plan for a discussion of the U.S. federal income tax consequences to you of your contract, policy, or plan.

Payments to Broker-Dealers and Financial Intermediaries

If you invest in the Fund under a variable insurance contract or a plan that offers a variable insurance contract as a plan option through a broker-dealer or other financial intermediary (such as a financial institution), the Fund and its related companies may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary's Website for more information.

JNL Series Trust published this content on April 27, 2026, and is solely responsible for the information contained herein. Distributed via EDGAR on April 27, 2026 at 12:14 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]