# EDGAR Filing Document

**Accession Number:** 0000277751
**File Stem:** 0001193125-25-251830
**Filing Date:** 2025-10
**Character Count:** 67295
**Document Hash:** 8644049e82ca0cdd93157397d041ca91
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-25-251830.hdr.sgml**: 20251028

**ACCESSION NUMBER**: 0001193125-25-251830

**CONFORMED SUBMISSION TYPE**: 497K

**PUBLIC DOCUMENT COUNT**: 4

**FILED AS OF DATE**: 20251028

**DATE AS OF CHANGE**: 20251027

**EFFECTIVENESS DATE**: 20251028

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** JANUS INVESTMENT FUND
- **CENTRAL INDEX KEY:** 0000277751

**ORGANIZATION NAME:**
- **EIN:** 840592523
- **STATE OF INCORPORATION:** MA

**FILING VALUES:**
- **FORM TYPE:** 497K
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 002-34393
- **FILM NUMBER:** 251420813

**BUSINESS ADDRESS:**
- **STREET 1:** 151 DETROIT STREET
- **CITY:** DENVER
- **STATE:** CO
- **ZIP:** 80206
- **BUSINESS PHONE:** 303-333-3863

**MAIL ADDRESS:**
- **STREET 1:** 151 DETROIT STREET
- **CITY:** DENVER
- **STATE:** CO
- **ZIP:** 80206

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** JANUS FUND /MD/
- **DATE OF NAME CHANGE:** 19870701

## Series and Classes Contracts Data

### Janus Henderson Small Cap Value Fund (Series ID: S000010480)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000028939 | Class L      | JSIVX           |
| C000028940 | Class T      | JSCVX           |
| C000077705 | Class A      | JDSAX           |
| C000077706 | Class C      | JCSCX           |
| C000077707 | Class I      | JSCOX           |
| C000077708 | Class R      | JDSRX           |
| C000077709 | Class S      | JISCX           |
| C000083526 | Class D      | JNPSX           |
| C000114879 | Class N      | JDSNX           |

[JANUS HENDERSON LOGO]

**Janus Henderson Small Cap Value Fund** 

Ticker: JDSAX Class A Shares JISCX Class S Shares JDSNX Class N Shares JSCVX Class T Shares <br> JCSCX Class C Shares JSCOX Class I Shares JDSRX Class R Shares

**Summary Prospectus dated October 28, 2025**

***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, reports to shareholders, and other information about the Fund online at janushenderson.com/info. You can also get this information at no cost by calling a Janus Henderson representative at 1-877-335-2687 or by sending an email request to prospectusrequest@janushenderson.com.***

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**Investment Objective**<br>

**Janus Henderson Small Cap Value Fund** seeks capital appreciation.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Fees and Expenses of the Fund**<br>

This table describes the fees and expenses that you may pay if you buy, hold, and sell Shares of the Fund. Each share class has different expenses, but represents an investment in the same Fund. For Class A Shares, you may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the Fund or in other Janus Henderson funds. More information about these and other discounts, as well as eligibility requirements for each share class, is available from your financial professional and in the "Purchases" section on page 57 of the Fund's Prospectus and in the "Purchases" section on page 72 of the Fund's Statement of Additional Information. In addition, please see Appendix A – Intermediary Sales Charge Waivers and Discounts. You may also incur brokerage commissions charged by your broker or financial intermediary when buying Class I Shares or Class N Shares of the Fund that are not reflected in the table or in the example below.

---

| | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|
| **SHAREHOLDER FEES**<br> (fees paid directly from your investment)<br>| **Class A** | **Class C** | **Class S** | **Class I** | **Class N** | **Class R** | **Class T** |
| &nbsp;&nbsp;&nbsp;&nbsp; Maximum Sales Charge (load) Imposed on Purchases (as a <br> percentage of offering price)<br>| 5.75% |  |  |  |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp; Maximum Deferred Sales Charge (load) (as a percentage of <br> the lower of original purchase price or redemption <br> proceeds)<br>|  | 1.00% |  |  |  |  |  |
| **ANNUAL FUND OPERATING EXPENSES**<br> (expenses that you pay each year as a percentage of the value <br> of your investment)<br>| **Class A** | **Class C** | **Class S** | **Class I** | **Class N** | **Class R** | **Class T** |
| Management Fees<sup>(1)</sup> <br>| 0.92% | 0.92% | 0.92% | 0.92% | 0.92% | 0.92% | 0.92% |
| Distribution/Service (12b-1) Fees | 0.25% | 1.00% | 0.25% |  |  | 0.50% |  |
| Other Expenses | 0.29% | 0.16% | 0.32% | 0.20% | 0.06% | 0.31% | 0.31% |
| Total Annual Fund Operating Expenses | 1.46% | 2.08% | 1.49% | 1.12% | 0.98% | 1.73% | 1.23% |

---

(1) This fee may adjust up or down monthly based on the Fund's performance relative to its benchmark index over the performance measurement period. For more information regarding performance-based advisory fees, refer to "Management Expenses" in the Fund's Prospectus.

**EXAMPLE:**

The Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and reinvest all dividends and distributions. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. Class C Shares automatically convert to Class A Shares after eight years. The Example for Class C Shares for the ten-year period reflects the conversion to Class A Shares. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

---

| | | | | |
|:---|:---|:---|:---|:---|
| **If Shares are redeemed:** | **1 Year** | **3 Years** | **5 Years** | **10 Years** |
| Class A Shares | &nbsp;&nbsp; $715 | &nbsp;&nbsp; $1010 | &nbsp;&nbsp; $1327 | &nbsp;&nbsp; $2221 |
| Class C Shares | &nbsp;&nbsp; $311 | &nbsp;&nbsp; $652 | &nbsp;&nbsp; $1119 | &nbsp;&nbsp; $2252 |
| Class S Shares | &nbsp;&nbsp; $152 | &nbsp;&nbsp; $471 | &nbsp;&nbsp; $813 | &nbsp;&nbsp; $1779 |
| Class I Shares | &nbsp;&nbsp; $114 | &nbsp;&nbsp; $356 | &nbsp;&nbsp; $617 | &nbsp;&nbsp; $1363 |

---

1 \| Janus Henderson Small Cap Value Fund

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---

| | | | | |
|:---|:---|:---|:---|:---|
| **If Shares are redeemed:** | **1 Year** | **3 Years** | **5 Years** | **10 Years** |
| Class N Shares | &nbsp;&nbsp; $100 | &nbsp;&nbsp; $312 | &nbsp;&nbsp; $542 | &nbsp;&nbsp; $1201 |
| Class R Shares | &nbsp;&nbsp; $176 | &nbsp;&nbsp; $545 | &nbsp;&nbsp; $939 | &nbsp;&nbsp; $2041 |
| Class T Shares | &nbsp;&nbsp; $125 | &nbsp;&nbsp; $390 | &nbsp;&nbsp; $676 | &nbsp;&nbsp; $1489 |

---

---

| | | | | |
|:---|:---|:---|:---|:---|
| **If Shares are not redeemed:** | **1 Year** | **3 Years** | **5 Years** | **10 Years** |
| Class A Shares | &nbsp;&nbsp; $715 | &nbsp;&nbsp; $1010 | &nbsp;&nbsp; $1327 | &nbsp;&nbsp; $2221 |
| Class C Shares | &nbsp;&nbsp; $211 | &nbsp;&nbsp; $652 | &nbsp;&nbsp; $1119 | &nbsp;&nbsp; $2252 |
| Class S Shares | &nbsp;&nbsp; $152 | &nbsp;&nbsp; $471 | &nbsp;&nbsp; $813 | &nbsp;&nbsp; $1779 |
| Class I Shares | &nbsp;&nbsp; $114 | &nbsp;&nbsp; $356 | &nbsp;&nbsp; $617 | &nbsp;&nbsp; $1363 |
| Class N Shares | &nbsp;&nbsp; $100 | &nbsp;&nbsp; $312 | &nbsp;&nbsp; $542 | &nbsp;&nbsp; $1201 |
| Class R Shares | &nbsp;&nbsp; $176 | &nbsp;&nbsp; $545 | &nbsp;&nbsp; $939 | &nbsp;&nbsp; $2041 |
| Class T Shares | &nbsp;&nbsp; $125 | &nbsp;&nbsp; $390 | &nbsp;&nbsp; $676 | &nbsp;&nbsp; $1489 |

---

**Portfolio Turnover:** The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 37% of the average value of its portfolio.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Principal investment strategies**<br>

The Fund pursues its investment objective by investing primarily in the common stocks of small companies and focuses on companies whose stock prices are believed to be undervalued by the Fund's portfolio management or that have fallen out of favor with the market. The Fund invests, under normal circumstances, at least 80% of its net assets (plus any borrowings for investment purposes) in equity securities of small companies whose market capitalization, at the time of purchase, is less than the 12-month maximum market capitalization for companies included in the Russell 2000<sup>®</sup> Value Index. The market capitalizations within the index will vary, but as of June 30, 2025, they ranged from approximately $18 million to $8.48 billion. From time to time, the Fund may invest in shares of companies through initial public offerings. The Fund may also invest in foreign securities, as well as in real estate investment trusts ("REITs") and similar REIT-like entities.

As defensive value managers, portfolio management generally looks for companies with:

• strong management teams;

• strong and stable balance sheets and solid recurring free cash flows;

• attractive relative and absolute valuation ratios or that have underperformed recently;

• favorable reward to risk characteristics;

• sustainable competitive advantages that are trading at attractive valuations; and

• strong long-term prospects.

Portfolio management's philosophy is to weigh a security's downside risk before considering its upside potential, which may help provide an element of capital preservation.

As part of its investment process, portfolio management considers environmental, social, and governance ("ESG") risks and opportunities ("ESG Factors") that it believes are financially material, alongside other fundamental investment factors. Examples of potential financially material ESG Factors include: corporate governance, company culture, exposure to climate change, and human capital management. To assess ESG Factors, portfolio management uses issuer reports, third-party data, and internally-generated analyses and may engage directly with issuers. ESG Factors are one of many considerations in the investment decision-making process, may not be determinative in deciding to include or exclude an investment from the portfolio, and may not be considered for every investment decision.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Principal investment risks**<br>

The biggest risk is that the Fund's returns will vary, and you could lose money. The Fund is designed for long-term investors seeking an equity portfolio, including common stocks. The principal risks associated with investing in the Fund are set forth below.

2 \| Janus Investment Fund

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***Market Risk.*** The value of the Fund's portfolio may decrease due to short-term market movements and over more prolonged market downturns. As a result, the Fund's net asset value may fluctuate and it may be more difficult to value or sell the Fund's holdings. Market risk may affect a single issuer, industry, economic sector, or the market as a whole. Market risk may be magnified if certain social, political, economic, and other conditions and events (such as financial institution failures, economic recessions, tariffs, trade disputes, terrorism, war, armed conflicts, including related sanctions, social unrest, natural disasters, and epidemics and pandemics) adversely interrupt the global economy and financial markets. It is important to understand that the value of your investment may fall, sometimes sharply, in response to changes in the market, and you could lose money.

***Value Investing Risk.*** Because different types of stocks tend to shift in and out of favor depending on market and economic conditions, "value" stocks may perform differently than other types of stocks and from the market as a whole, and can continue to be undervalued by the market for long periods of time. It is also possible that a value stock will never appreciate to the extent expected.

***Small-Sized Companies Risk.*** Investments in securities issued by small-sized companies, which can include smaller companies offering emerging products or services, may involve greater risks than are customarily associated with larger, more established companies. Securities issued by small-sized companies tend to be more volatile and somewhat more speculative than securities issued by larger or more established companies and may underperform as compared to the securities of larger or more established companies. These holdings are also subject to wider price fluctuations and tend to be less liquid than stocks of larger or more established companies, which could have a significant adverse effect on the Fund's returns, especially as market conditions change.

***Equity Securities Risk.*** Equity securities are subject to changes in value, and their values may be more volatile than those of other asset classes. The value of the Fund's portfolio may decrease if the value of an individual company or security, or multiple companies or securities, in the portfolio decreases. Further, regardless of how well individual companies or securities perform, the value of the Fund's portfolio could also decrease if there are deteriorating economic or market conditions or perceptions regarding the industries in which the issuers of securities the Fund holds participate.

***Industry and Sector Risk.*** Although the Fund does not concentrate its investments in specific industries, it may have a significant portion of its assets invested in securities of companies conducting similar business or businesses within the same economic sector. Companies in the same industry or economic sector may be similarly affected by negative economic or market events, making the Fund more vulnerable to unfavorable developments than funds that invest more broadly. As the Fund's portfolio becomes more concentrated, the Fund is less able to spread risk and potentially reduce the risk of loss and volatility. As the Fund's holdings change over time, the Fund's exposure to a particular economic sector may fluctuate.

• ***Financial Services Sector Risk.*** To the extent the Fund invests its assets in the financial services sector, the Fund will have exposure to the risks inherent to the financial services sector. Financial services companies may be adversely affected by changes in regulatory framework or interest rates that may negatively affect financial services businesses; exposure of a financial institution to a nondiversified or concentrated loan portfolio; exposure to financial leverage and/or investments or agreements that, under certain circumstances, may lead to losses; and the risk that a market shock or other unexpected market, economic, political, regulatory, or other event, including a banking crisis or financial emergency, might lead to a sudden decline in the values of most or all financial services companies.

***REIT Risk.*** REITs are subject to certain risks inherent in the direct ownership of real estate, including without limitation, a possible lack of mortgage funds and associated interest rate risks, overbuilding, property vacancies, increases in property taxes and operating expenses, changes in zoning laws, losses due to environmental damages and changes in neighborhood values and appeal to purchasers. In addition, a REIT could fail to qualify for tax-free pass-through of its income under the Internal Revenue Code of 1986, as amended, or fail to maintain its exemption from registration under the Investment Company Act of 1940, as amended, which could produce adverse economic consequences for the REIT and its investors, including the Fund. Dividends received by the Fund from a REIT generally will not constitute qualified dividend income.

***Portfolio Management Risk.*** The Fund is an actively managed investment portfolio and is therefore subject to the risk that the investment strategies and research process employed for the Fund may fail to produce the intended results. Accordingly, the Fund may underperform benchmark indices or other funds with similar investment objectives.

***Initial Public Offering Risk.*** The Fund's purchase of shares issued in an initial public offering ("IPO") exposes it to the risks associated with companies that have little operating history as public companies, as well as to the risks inherent in those

3 \| Janus Henderson Small Cap Value Fund

------

sectors of the market where these new issuers operate. There can be no assurance that the Fund will identify favorable IPO investment opportunities.

***Foreign Exposure Risk.*** Foreign markets can be more volatile than the U.S. market. As a result, the Fund's returns and net asset value may be affected by fluctuations in currency exchange rates or political or economic conditions in a particular country. Investments in foreign securities, particularly those of issuers located in emerging market countries, tend to have greater exposure to liquidity risk than domestic securities. In some foreign markets, there may not be protection against failure by other parties to complete transactions. It may not be possible for the Fund to repatriate capital, dividends, interest, and other income from a particular country or governmental entity. In addition, a market swing in one or more countries or regions where the Fund has invested a significant amount of its assets may have a greater effect on the Fund's performance than it would in a more geographically diversified portfolio.

***ESG Integration Risk.*** There is a risk that considering ESG Factors as part of the Fund's investment process may fail to produce the intended results or that the Fund may perform differently from funds that have a similar investment style but do not formally incorporate such considerations in their strategy. Information related to ESG Factors provided by issuers and third parties, which portfolio management may utilize, continues to develop and may be incomplete or inaccurate, use different methodologies, or be applied differently across issuers and industries.

*An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.*

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Performance information**<br>

The following information provides some indication of the risks of investing in the Fund by showing how the Fund's performance has varied over time.

The bar chart depicts the change in performance from year to year during the periods indicated. The bar chart figures do not include any applicable sales charges that an investor may pay when they buy or sell Class A Shares or Class C Shares of the Fund. If sales charges were included, the returns would be lower. The table compares the Fund's average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions. For certain periods, the Fund's performance reflects the effect of expense waivers. Without the effect of these expense waivers, the performance shown would have been lower.

*The Fund's past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-877-335-2687*.

---

| |
|:---|
| **Annual Total Returns for Class T Shares** (calendar year-end) |
| &nbsp;&nbsp; ![](g728271img48d98cf21.jpg)<br>|

---

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

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| | | | | | |
|:---|:---|:---|:---|:---|:---|
| **Best Quarter:** | 4th Quarter 2020 | **25.59%** | **Worst Quarter:** | 1st Quarter 2020 | **– 32.64%** |

---

Class T Shares' year-to-date return as of the calendar quarter ended September 30, 2025 was 4.59%.

4 \| Janus Investment Fund

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| | | | |
|:---|:---|:---|:---|
| **Average Annual Total Returns** (periods ended 12/31/24) |  |  |  |
|  | **1 Year** | **5 Years** | **10 Years** |
| **Class T Shares** |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp; Return Before Taxes | &nbsp;&nbsp;&nbsp;&nbsp; 6.16% | &nbsp;&nbsp;&nbsp;&nbsp; 4.33% | &nbsp;&nbsp;&nbsp;&nbsp; 6.48% |
| &nbsp;&nbsp;&nbsp;&nbsp; Return After Taxes on Distributions | &nbsp;&nbsp;&nbsp;&nbsp; 3.75% | &nbsp;&nbsp;&nbsp;&nbsp; 3.23% | &nbsp;&nbsp;&nbsp;&nbsp; 5.01% |
| &nbsp;&nbsp;&nbsp;&nbsp; Return After Taxes on Distributions and Sale of Fund Shares<sup>(1)</sup> <br>| &nbsp;&nbsp;&nbsp;&nbsp; 5.58% | &nbsp;&nbsp;&nbsp;&nbsp; 3.34% | &nbsp;&nbsp;&nbsp;&nbsp; 4.89% |
| **Class A Shares** – Return Before Taxes<sup>(2)</sup> <br>| &nbsp;&nbsp;&nbsp;&nbsp; – 0.15% | &nbsp;&nbsp;&nbsp;&nbsp; 2.90% | &nbsp;&nbsp;&nbsp;&nbsp; 5.63% |
| **Class C Shares** – Return Before Taxes<sup>(3)</sup> <br>| &nbsp;&nbsp;&nbsp;&nbsp; 4.41% | &nbsp;&nbsp;&nbsp;&nbsp; 3.47% | &nbsp;&nbsp;&nbsp;&nbsp; 5.61% |
| **Class S Shares** – Return Before Taxes | &nbsp;&nbsp;&nbsp;&nbsp; 5.91% | &nbsp;&nbsp;&nbsp;&nbsp; 4.07% | &nbsp;&nbsp;&nbsp;&nbsp; 6.20% |
| **Class I Shares** – Return Before Taxes | &nbsp;&nbsp;&nbsp;&nbsp; 6.32% | &nbsp;&nbsp;&nbsp;&nbsp; 4.44% | &nbsp;&nbsp;&nbsp;&nbsp; 6.59% |
| **Class N Shares** – Return Before Taxes | &nbsp;&nbsp;&nbsp;&nbsp; 6.43% | &nbsp;&nbsp;&nbsp;&nbsp; 4.59% | &nbsp;&nbsp;&nbsp;&nbsp; 6.73% |
| **Class R Shares** – Return Before Taxes | &nbsp;&nbsp;&nbsp;&nbsp; 5.63% | &nbsp;&nbsp;&nbsp;&nbsp; 3.80% | &nbsp;&nbsp;&nbsp;&nbsp; 5.94% |
| &nbsp;&nbsp;&nbsp;&nbsp; Russell 3000<sup>®</sup> Index<br> (reflects no deduction for expenses, fees, or taxes)<br>| &nbsp;&nbsp;&nbsp;&nbsp; 23.81% | &nbsp;&nbsp;&nbsp;&nbsp; 13.86% | &nbsp;&nbsp;&nbsp;&nbsp; 12.55% |
| &nbsp;&nbsp;&nbsp;&nbsp; Russell 2000<sup>®</sup> Value Index<br> (reflects no deduction for expenses, fees, or taxes)<br>| &nbsp;&nbsp;&nbsp;&nbsp; 8.05% | &nbsp;&nbsp;&nbsp;&nbsp; 7.29% | &nbsp;&nbsp;&nbsp;&nbsp; 7.14% |

---

(1) If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund's other return figures.

(2) Calculated assuming maximum permitted sales loads.

(3) The one year return is calculated to include the contingent deferred sales charge.

The Fund's broad-based benchmark index is the Russell 3000 Index, due to regulatory requirements. The Fund's additional benchmark index is the Russell 2000 Value Index, which has investment characteristics similar to those of the Fund. The indices are described below.

• The Russell 3000 Index measures the performance of the largest 3,000 U.S. companies.

• The Russell 2000 Value Index measures the performance of those Russell 2000 companies with lower price-to-book ratios and lower forecasted growth values.

After-tax returns are calculated using the historically highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

After-tax returns are only shown for Class T Shares of the Fund. After-tax returns for the other classes of Shares will vary from those shown for Class T Shares due to varying sales charges (as applicable), fees, and expenses among the classes.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Management**<br>

**Investment Adviser:** Janus Henderson Investors US LLC

**Portfolio Management: Craig Kempler**, CFA, is Executive Vice President and Co-Portfolio Manager of the Fund, which he has co-managed since October 2017. **Justin Tugman**, CFA, is Executive Vice President and Co-Portfolio Manager of the Fund, which he has co-managed since March 2009.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

5 \| Janus Henderson Small Cap Value Fund

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**Purchase and sale of Fund shares**<br>

**Minimum Investment Requirements** 

---

| | |
|:---|:---|
| **Class A Shares, Class C Shares**\***, Class S Shares, Class I Shares**†**, Class R Shares, and Class T Shares** |  |
| Non-retirement accounts | $2,500\*\* |
| Certain tax-advantaged accounts or UTMA accounts | $500 |
| **Class N Shares** |  |
| Retirement investors (investing through an adviser-assisted, employer-sponsored retirement plan) |  |
| Retail investors (investing through a financial intermediary omnibus account) | $2,500\*\*\* |
| Institutional investors (investing directly with the Fund) | $1000000 |

---

†

Exceptions to these minimums may apply for certain tax-advantaged, tax-qualified and retirement plans, including health savings accounts, accounts held through certain wrap programs, and certain retail brokerage accounts.

\*

The maximum purchase in Class C Shares is $250,000 for any single purchase.

\*\*

Class A, Class C, Class S, and Class T shares held through certain supermarket and/or self-directed brokerage accounts, or through wrap programs, may not be subject to these minimums. Please contact your financial intermediary for more information. For Class R shareholders, there is no investment minimum for defined contribution plans. Investors in a defined contribution plan through a third party administrator should refer to their plan document or contact their plan administrator for additional information regarding account minimums. <br>

\*\*\*

Investors in certain tax-advantaged accounts or accounts held through certain wrap programs or bank trust platforms may not be subject to this minimum.

Purchases, exchanges, and redemptions can generally be made only through institutional channels, such as financial intermediaries and retirement platforms. You should contact your financial intermediary or refer to your plan documents for information on how to invest in the Fund. Requests must be received in good order by the Fund or its agents (financial intermediary or plan sponsor, if applicable) prior to the close of the trading session of the New York Stock Exchange in order to receive that day's net asset value. For additional information, refer to "Purchases," "Exchanges," and/or "Redemptions" in the Prospectus.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Tax information**<br>

The Fund's distributions are taxable, and will be taxed as ordinary income or capital gains, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account (in which case you may be taxed upon withdrawal of your investment from such account).

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Payments to broker-dealers and other financial intermediaries**<br>

If you purchase Class A Shares, Class C Shares, Class S Shares, Class I Shares, Class R Shares, or Class T Shares of the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund or its distributor (or its affiliates) 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 or to recommend one share class over another. Ask your salesperson or visit your financial intermediary's website for more information.

6 \| Janus Investment Fund

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[JANUS HENDERSON LOGO]

**Janus Henderson Small Cap Value Fund** 

Ticker: JNPSX Class D Shares

**Summary Prospectus dated October 28, 2025**

***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, reports to shareholders, and other information about the Fund online at janushenderson.com/reports. You can also get this information at no cost by calling a Janus Henderson representative at 1-800-525-3713 or by sending an email request to prospectusorder@janushenderson.com.***

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**Investment Objective**<br>

**Janus Henderson Small Cap Value Fund** seeks capital appreciation.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Fees and Expenses of the Fund**<br>

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

---

| | |
|:---|:---|
| **ANNUAL FUND OPERATING EXPENSES**<br> (expenses that you pay each year as a percentage of the value of your investment)<br>| **Class D** |
| Management Fees<sup>(1)</sup> <br>| 0.92% |
| Other Expenses | 0.20% |
| Total Annual Fund Operating Expenses | 1.12% |

---

(1) This fee may adjust up or down monthly based on the Fund's performance relative to its benchmark index over the performance measurement period. For more information regarding performance-based advisory fees, refer to "Management Expenses" in the Fund's Prospectus.

**EXAMPLE:**

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

---

| | | | | |
|:---|:---|:---|:---|:---|
|  | **1 Year** | **3 Years** | **5 Years** | **10 Years** |
| Class D Shares | &nbsp;&nbsp; $114 | &nbsp;&nbsp; $356 | &nbsp;&nbsp; $617 | &nbsp;&nbsp; $1363 |

---

**Portfolio Turnover:** The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 37% of the average value of its portfolio.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Principal investment strategies**<br>

The Fund pursues its investment objective by investing primarily in the common stocks of small companies and focuses on companies whose stock prices are believed to be undervalued by the Fund's portfolio management or that have fallen out of favor with the market. The Fund invests, under normal circumstances, at least 80% of its net assets (plus any borrowings for investment purposes) in equity securities of small companies whose market capitalization, at the time of purchase, is less than the 12-month maximum market capitalization for companies included in the Russell 2000<sup>®</sup> Value Index. The market capitalizations within the index will vary, but as of June 30, 2025, they ranged from approximately $18 million to $8.48 billion. From time to time, the Fund may invest in shares of companies through initial public offerings. The Fund may also invest in foreign securities, as well as in real estate investment trusts ("REITs") and similar REIT-like entities.

As defensive value managers, portfolio management generally looks for companies with:

• strong management teams;

• strong and stable balance sheets and solid recurring free cash flows;

• attractive relative and absolute valuation ratios or that have underperformed recently;

• favorable reward to risk characteristics;

• sustainable competitive advantages that are trading at attractive valuations; and

1 \| Janus Henderson Small Cap Value Fund

------

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• strong long-term prospects.

Portfolio management's philosophy is to weigh a security's downside risk before considering its upside potential, which may help provide an element of capital preservation.

As part of its investment process, portfolio management considers environmental, social, and governance ("ESG") risks and opportunities ("ESG Factors") that it believes are financially material, alongside other fundamental investment factors. Examples of potential financially material ESG Factors include: corporate governance, company culture, exposure to climate change, and human capital management. To assess ESG Factors, portfolio management uses issuer reports, third-party data, and internally-generated analyses and may engage directly with issuers. ESG Factors are one of many considerations in the investment decision-making process, may not be determinative in deciding to include or exclude an investment from the portfolio, and may not be considered for every investment decision.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Principal investment risks**<br>

The biggest risk is that the Fund's returns will vary, and you could lose money. The Fund is designed for long-term investors seeking an equity portfolio, including common stocks. The principal risks associated with investing in the Fund are set forth below.

***Market Risk.*** The value of the Fund's portfolio may decrease due to short-term market movements and over more prolonged market downturns. As a result, the Fund's net asset value may fluctuate and it may be more difficult to value or sell the Fund's holdings. Market risk may affect a single issuer, industry, economic sector, or the market as a whole. Market risk may be magnified if certain social, political, economic, and other conditions and events (such as financial institution failures, economic recessions, tariffs, trade disputes, terrorism, war, armed conflicts, including related sanctions, social unrest, natural disasters, and epidemics and pandemics) adversely interrupt the global economy and financial markets. It is important to understand that the value of your investment may fall, sometimes sharply, in response to changes in the market, and you could lose money.

***Value Investing Risk.*** Because different types of stocks tend to shift in and out of favor depending on market and economic conditions, "value" stocks may perform differently than other types of stocks and from the market as a whole, and can continue to be undervalued by the market for long periods of time. It is also possible that a value stock will never appreciate to the extent expected.

***Small-Sized Companies Risk.*** Investments in securities issued by small-sized companies, which can include smaller companies offering emerging products or services, may involve greater risks than are customarily associated with larger, more established companies. Securities issued by small-sized companies tend to be more volatile and somewhat more speculative than securities issued by larger or more established companies and may underperform as compared to the securities of larger or more established companies. These holdings are also subject to wider price fluctuations and tend to be less liquid than stocks of larger or more established companies, which could have a significant adverse effect on the Fund's returns, especially as market conditions change.

***Equity Securities Risk.*** Equity securities are subject to changes in value, and their values may be more volatile than those of other asset classes. The value of the Fund's portfolio may decrease if the value of an individual company or security, or multiple companies or securities, in the portfolio decreases. Further, regardless of how well individual companies or securities perform, the value of the Fund's portfolio could also decrease if there are deteriorating economic or market conditions or perceptions regarding the industries in which the issuers of securities the Fund holds participate.

***Industry and Sector Risk.*** Although the Fund does not concentrate its investments in specific industries, it may have a significant portion of its assets invested in securities of companies conducting similar business or businesses within the same economic sector. Companies in the same industry or economic sector may be similarly affected by negative economic or market events, making the Fund more vulnerable to unfavorable developments than funds that invest more broadly. As the Fund's portfolio becomes more concentrated, the Fund is less able to spread risk and potentially reduce the risk of loss and volatility. As the Fund's holdings change over time, the Fund's exposure to a particular economic sector may fluctuate.

• ***Financial Services Sector Risk.*** To the extent the Fund invests its assets in the financial services sector, the Fund will have exposure to the risks inherent to the financial services sector. Financial services companies may be adversely affected by changes in regulatory framework or interest rates that may negatively affect financial services businesses; exposure of a financial institution to a nondiversified or concentrated loan portfolio; exposure to financial leverage and/or investments or

2 \| Janus Investment Fund

------

agreements that, under certain circumstances, may lead to losses; and the risk that a market shock or other unexpected market, economic, political, regulatory, or other event, including a banking crisis or financial emergency, might lead to a sudden decline in the values of most or all financial services companies.

***REIT Risk.*** REITs are subject to certain risks inherent in the direct ownership of real estate, including without limitation, a possible lack of mortgage funds and associated interest rate risks, overbuilding, property vacancies, increases in property taxes and operating expenses, changes in zoning laws, losses due to environmental damages and changes in neighborhood values and appeal to purchasers. In addition, a REIT could fail to qualify for tax-free pass-through of its income under the Internal Revenue Code of 1986, as amended, or fail to maintain its exemption from registration under the Investment Company Act of 1940, as amended, which could produce adverse economic consequences for the REIT and its investors, including the Fund. Dividends received by the Fund from a REIT generally will not constitute qualified dividend income.

***Portfolio Management Risk.*** The Fund is an actively managed investment portfolio and is therefore subject to the risk that the investment strategies and research process employed for the Fund may fail to produce the intended results. Accordingly, the Fund may underperform benchmark indices or other funds with similar investment objectives.

***Initial Public Offering Risk.*** The Fund's purchase of shares issued in an initial public offering ("IPO") exposes it to the risks associated with companies that have little operating history as public companies, as well as to the risks inherent in those sectors of the market where these new issuers operate. There can be no assurance that the Fund will identify favorable IPO investment opportunities.

***Foreign Exposure Risk.*** Foreign markets can be more volatile than the U.S. market. As a result, the Fund's returns and net asset value may be affected by fluctuations in currency exchange rates or political or economic conditions in a particular country. Investments in foreign securities, particularly those of issuers located in emerging market countries, tend to have greater exposure to liquidity risk than domestic securities. In some foreign markets, there may not be protection against failure by other parties to complete transactions. It may not be possible for the Fund to repatriate capital, dividends, interest, and other income from a particular country or governmental entity. In addition, a market swing in one or more countries or regions where the Fund has invested a significant amount of its assets may have a greater effect on the Fund's performance than it would in a more geographically diversified portfolio.

***ESG Integration Risk.*** There is a risk that considering ESG Factors as part of the Fund's investment process may fail to produce the intended results or that the Fund may perform differently from funds that have a similar investment style but do not formally incorporate such considerations in their strategy. Information related to ESG Factors provided by issuers and third parties, which portfolio management may utilize, continues to develop and may be incomplete or inaccurate, use different methodologies, or be applied differently across issuers and industries.

*An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.*

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Performance information**<br>

The following information provides some indication of the risks of investing in the Fund by showing how the Fund's performance has varied over time.

The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund's average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions. For certain periods, the Fund's performance reflects the effect of expense waivers. Without the effect of these expense waivers, the performance shown would have been lower.

*The Fund's past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/allfunds or by calling 1-800-525-3713.* 

3 \| Janus Henderson Small Cap Value Fund

------

---

| |
|:---|
| **Annual Total Returns for Class D Shares** (calendar year-end) |
| &nbsp;&nbsp; ![](g730994img6845811f1.jpg)<br>|

---

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| **Best Quarter:** | 4th Quarter 2020 | **25.65%** | **Worst Quarter:** | 1st Quarter 2020 | **– 32.58%** |

---

Class D Shares' year-to-date return as of the calendar quarter ended September 30, 2025 was 4.66%.

---

| | | | |
|:---|:---|:---|:---|
| **Average Annual Total Returns** (periods ended 12/31/24) |  |  |  |
|  | **1 Year** | **5 Years** | **10 Years** |
| **Class D Shares** |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp; Return Before Taxes | &nbsp;&nbsp;&nbsp;&nbsp; 6.29% | &nbsp;&nbsp;&nbsp;&nbsp; 4.43% | &nbsp;&nbsp;&nbsp;&nbsp; 6.57% |
| &nbsp;&nbsp;&nbsp;&nbsp; Return After Taxes on Distributions | &nbsp;&nbsp;&nbsp;&nbsp; 3.86% | &nbsp;&nbsp;&nbsp;&nbsp; 3.30% | &nbsp;&nbsp;&nbsp;&nbsp; 5.07% |
| &nbsp;&nbsp;&nbsp;&nbsp; Return After Taxes on Distributions and Sale of Fund Shares<sup>(1)</sup> <br>| &nbsp;&nbsp;&nbsp;&nbsp; 5.68% | &nbsp;&nbsp;&nbsp;&nbsp; 3.41% | &nbsp;&nbsp;&nbsp;&nbsp; 4.96% |
| &nbsp;&nbsp;&nbsp;&nbsp; Russell 3000<sup>®</sup> Index<br> (reflects no deduction for expenses, fees, or taxes)<br>| &nbsp;&nbsp;&nbsp;&nbsp; 23.81% | &nbsp;&nbsp;&nbsp;&nbsp; 13.86% | &nbsp;&nbsp;&nbsp;&nbsp; 12.55% |
| &nbsp;&nbsp;&nbsp;&nbsp; Russell 2000<sup>®</sup> Value Index<br> (reflects no deduction for expenses, fees, or taxes)<br>| &nbsp;&nbsp;&nbsp;&nbsp; 8.05% | &nbsp;&nbsp;&nbsp;&nbsp; 7.29% | &nbsp;&nbsp;&nbsp;&nbsp; 7.14% |

---

(1) If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund's other return figures.

The Fund's broad-based benchmark index is the Russell 3000 Index, due to regulatory requirements. The Fund's additional benchmark index is the Russell 2000 Value Index, which has investment characteristics similar to those of the Fund. The indices are described below.

• The Russell 3000 Index measures the performance of the largest 3,000 U.S. companies.

• The Russell 2000 Value Index measures the performance of those Russell 2000 companies with lower price-to-book ratios and lower forecasted growth values. After-tax returns are calculated using the historically highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Management**<br>

**Investment Adviser:** Janus Henderson Investors US LLC

**Portfolio Management: Craig Kempler**, CFA, is Executive Vice President and Co-Portfolio Manager of the Fund, which he has co-managed since October 2017. **Justin Tugman**, CFA, is Executive Vice President and Co-Portfolio Manager of the Fund, which he has co-managed since March 2009.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

4 \| Janus Investment Fund

------

**Purchase and sale of Fund shares**<br>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

---

| | |
|:---|:---|
| **Minimum Investment Requirements** |  |
| To open a new regular Fund account | $2500 |
| To open a new regular Fund account with an automatic investment program of $50 per month | $100 |
| To open a new UTMA account, Coverdell Education Savings Account, or a retirement Fund account |  |
| &nbsp;&nbsp;&nbsp;&nbsp; • without an automatic investment program | $1000 |
| &nbsp;&nbsp;&nbsp;&nbsp; • with an automatic investment program of $50 per month | $100 |
| To add to any existing type of Fund account without an automatic investment program | $50 |

---

You may generally purchase, exchange, or redeem Fund Shares on any business day by written request, telephone, and in most cases, online at janushenderson.com/individual. You may conduct transactions by mail (Janus Henderson, P.O. Box 219109, Kansas City, MO 64121-9109), or by telephone at 1-800-525-3713. Purchase, exchange, or redemption requests must be received in good order by the Fund or its agents prior to the close of the trading session of the New York Stock Exchange in order to receive that day's net asset value. For additional information, refer to "To Open an Account or Buy Shares," "To Exchange Shares," and/or "To Sell Shares" in the Prospectus.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Tax information**<br>

The Fund's distributions are taxable, and will be taxed as ordinary income or capital gains, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account (in which case you may be taxed upon withdrawal of your investment from such account).

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Payments to broker-dealers and other financial intermediaries**<br>

With respect to share classes not offered in this Prospectus, the Fund or its distributor (or its affiliates) pay select broker-dealer firms or other financial intermediaries for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing a broker-dealer or other intermediary or a salesperson to recommend the Fund over another investment or to recommend one share class over another.

5 \| Janus Henderson Small Cap Value Fund

------

[JANUS HENDERSON LOGO]

**Janus Henderson Small Cap Value Fund** 

Ticker: JSIVX Class L Shares\*

\* Class L Shares are closed.

**Summary Prospectus dated October 28, 2025**

***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, reports to shareholders, and other information about the Fund online at janushenderson.com/info. You can also get this information at no cost by calling a Janus Henderson representative at 1-877-335-2687 or by sending an email request to prospectusrequest@janushenderson.com.***

------

**Investment Objective**<br>

**Janus Henderson Small Cap Value Fund** seeks capital appreciation.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Fees and Expenses of the Fund**<br>

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

---

| | |
|:---|:---|
| **ANNUAL FUND OPERATING EXPENSES**<br> (expenses that you pay each year as a percentage of the value of your investment)<br>| **Class L** |
| Management Fees<sup>(1)</sup> <br>| 0.92% |
| Other Expenses | 0.26% |
| Total Annual Fund Operating Expenses | 1.18% |

---

(1) This fee may adjust up or down monthly based on the Fund's performance relative to its benchmark index over the performance measurement period. For more information regarding performance-based advisory fees, refer to "Management Expenses" in the Fund's Prospectus.

**EXAMPLE:**

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

---

| | | | | |
|:---|:---|:---|:---|:---|
|  | **1 Year** | **3 Years** | **5 Years** | **10 Years** |
| Class L Shares | &nbsp;&nbsp; $120 | &nbsp;&nbsp; $375 | &nbsp;&nbsp; $649 | &nbsp;&nbsp; $1432 |

---

**Portfolio Turnover:** The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 37% of the average value of its portfolio.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Principal investment strategies**<br>

The Fund pursues its investment objective by investing primarily in the common stocks of small companies and focuses on companies whose stock prices are believed to be undervalued by the Fund's portfolio management or that have fallen out of favor with the market. The Fund invests, under normal circumstances, at least 80% of its net assets (plus any borrowings for investment purposes) in equity securities of small companies whose market capitalization, at the time of purchase, is less than the 12-month maximum market capitalization for companies included in the Russell 2000<sup>®</sup> Value Index. The market capitalizations within the index will vary, but as of June 30, 2025, they ranged from approximately $18 million to $8.48 billion. From time to time, the Fund may invest in shares of companies through initial public offerings. The Fund may also invest in foreign securities, as well as in real estate investment trusts ("REITs") and similar REIT-like entities.

As defensive value managers, portfolio management generally looks for companies with:

• strong management teams;

• strong and stable balance sheets and solid recurring free cash flows;

• attractive relative and absolute valuation ratios or that have underperformed recently;

• favorable reward to risk characteristics;

1 \| Janus Henderson Small Cap Value Fund

------

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

• sustainable competitive advantages that are trading at attractive valuations; and

• strong long-term prospects.

Portfolio management's philosophy is to weigh a security's downside risk before considering its upside potential, which may help provide an element of capital preservation.

As part of its investment process, portfolio management considers environmental, social, and governance ("ESG") risks and opportunities ("ESG Factors") that it believes are financially material, alongside other fundamental investment factors. Examples of potential financially material ESG Factors include: corporate governance, company culture, exposure to climate change, and human capital management. To assess ESG Factors, portfolio management uses issuer reports, third-party data, and internally-generated analyses and may engage directly with issuers. ESG Factors are one of many considerations in the investment decision-making process, may not be determinative in deciding to include or exclude an investment from the portfolio, and may not be considered for every investment decision.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Principal investment risks**<br>

The biggest risk is that the Fund's returns will vary, and you could lose money. The Fund is designed for long-term investors seeking an equity portfolio, including common stocks. The principal risks associated with investing in the Fund are set forth below.

***Market Risk.*** The value of the Fund's portfolio may decrease due to short-term market movements and over more prolonged market downturns. As a result, the Fund's net asset value may fluctuate and it may be more difficult to value or sell the Fund's holdings. Market risk may affect a single issuer, industry, economic sector, or the market as a whole. Market risk may be magnified if certain social, political, economic, and other conditions and events (such as financial institution failures, economic recessions, tariffs, trade disputes, terrorism, war, armed conflicts, including related sanctions, social unrest, natural disasters, and epidemics and pandemics) adversely interrupt the global economy and financial markets. It is important to understand that the value of your investment may fall, sometimes sharply, in response to changes in the market, and you could lose money.

***Value Investing Risk.*** Because different types of stocks tend to shift in and out of favor depending on market and economic conditions, "value" stocks may perform differently than other types of stocks and from the market as a whole, and can continue to be undervalued by the market for long periods of time. It is also possible that a value stock will never appreciate to the extent expected.

***Small-Sized Companies Risk.*** Investments in securities issued by small-sized companies, which can include smaller companies offering emerging products or services, may involve greater risks than are customarily associated with larger, more established companies. Securities issued by small-sized companies tend to be more volatile and somewhat more speculative than securities issued by larger or more established companies and may underperform as compared to the securities of larger or more established companies. These holdings are also subject to wider price fluctuations and tend to be less liquid than stocks of larger or more established companies, which could have a significant adverse effect on the Fund's returns, especially as market conditions change.

***Equity Securities Risk.*** Equity securities are subject to changes in value, and their values may be more volatile than those of other asset classes. The value of the Fund's portfolio may decrease if the value of an individual company or security, or multiple companies or securities, in the portfolio decreases. Further, regardless of how well individual companies or securities perform, the value of the Fund's portfolio could also decrease if there are deteriorating economic or market conditions or perceptions regarding the industries in which the issuers of securities the Fund holds participate.

***Industry and Sector Risk.*** Although the Fund does not concentrate its investments in specific industries, it may have a significant portion of its assets invested in securities of companies conducting similar business or businesses within the same economic sector. Companies in the same industry or economic sector may be similarly affected by negative economic or market events, making the Fund more vulnerable to unfavorable developments than funds that invest more broadly. As the Fund's portfolio becomes more concentrated, the Fund is less able to spread risk and potentially reduce the risk of loss and volatility. As the Fund's holdings change over time, the Fund's exposure to a particular economic sector may fluctuate.

• ***Financial Services Sector Risk.*** To the extent the Fund invests its assets in the financial services sector, the Fund will have exposure to the risks inherent to the financial services sector. Financial services companies may be adversely affected by changes in regulatory framework or interest rates that may negatively affect financial services businesses; exposure of a

2 \| Janus Investment Fund

------

financial institution to a nondiversified or concentrated loan portfolio; exposure to financial leverage and/or investments or agreements that, under certain circumstances, may lead to losses; and the risk that a market shock or other unexpected market, economic, political, regulatory, or other event, including a banking crisis or financial emergency, might lead to a sudden decline in the values of most or all financial services companies.

***REIT Risk.*** REITs are subject to certain risks inherent in the direct ownership of real estate, including without limitation, a possible lack of mortgage funds and associated interest rate risks, overbuilding, property vacancies, increases in property taxes and operating expenses, changes in zoning laws, losses due to environmental damages and changes in neighborhood values and appeal to purchasers. In addition, a REIT could fail to qualify for tax-free pass-through of its income under the Internal Revenue Code of 1986, as amended, or fail to maintain its exemption from registration under the Investment Company Act of 1940, as amended, which could produce adverse economic consequences for the REIT and its investors, including the Fund. Dividends received by the Fund from a REIT generally will not constitute qualified dividend income.

***Portfolio Management Risk.*** The Fund is an actively managed investment portfolio and is therefore subject to the risk that the investment strategies and research process employed for the Fund may fail to produce the intended results. Accordingly, the Fund may underperform benchmark indices or other funds with similar investment objectives.

***Initial Public Offering Risk.*** The Fund's purchase of shares issued in an initial public offering ("IPO") exposes it to the risks associated with companies that have little operating history as public companies, as well as to the risks inherent in those sectors of the market where these new issuers operate. There can be no assurance that the Fund will identify favorable IPO investment opportunities.

***Foreign Exposure Risk.*** Foreign markets can be more volatile than the U.S. market. As a result, the Fund's returns and net asset value may be affected by fluctuations in currency exchange rates or political or economic conditions in a particular country. Investments in foreign securities, particularly those of issuers located in emerging market countries, tend to have greater exposure to liquidity risk than domestic securities. In some foreign markets, there may not be protection against failure by other parties to complete transactions. It may not be possible for the Fund to repatriate capital, dividends, interest, and other income from a particular country or governmental entity. In addition, a market swing in one or more countries or regions where the Fund has invested a significant amount of its assets may have a greater effect on the Fund's performance than it would in a more geographically diversified portfolio.

***ESG Integration Risk.*** There is a risk that considering ESG Factors as part of the Fund's investment process may fail to produce the intended results or that the Fund may perform differently from funds that have a similar investment style but do not formally incorporate such considerations in their strategy. Information related to ESG Factors provided by issuers and third parties, which portfolio management may utilize, continues to develop and may be incomplete or inaccurate, use different methodologies, or be applied differently across issuers and industries.

*An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.*

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Performance information**<br>

The following information provides some indication of the risks of investing in the Fund by showing how the Fund's performance has varied over time.

The bar chart depicts the change in performance from year to year during the periods indicated. The table compares the Fund's average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more additional indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions. For certain periods, the Fund's performance reflects the effect of expense waivers. Without the effect of these expense waivers, the performance shown would have been lower.

*The Fund's past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janushenderson.com/performance or by calling 1-877-335-2687*.

3 \| Janus Henderson Small Cap Value Fund

------

---

| |
|:---|
| **Annual Total Returns for Class L Shares** (calendar year-end) |
| &nbsp;&nbsp; ![](g748315img55c693cf1.jpg)<br>|

---

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

---

| | | | | | |
|:---|:---|:---|:---|:---|:---|
| **Best Quarter:** | 4th Quarter 2020 | **25.62%** | **Worst Quarter:** | 1st Quarter 2020 | **– 32.59%** |

---

Class L Shares' year-to-date return as of the calendar quarter ended September 30, 2025 was 4.76%.

---

| | | | |
|:---|:---|:---|:---|
| **Average Annual Total Returns** (periods ended 12/31/24) |  |  |  |
|  | **1 Year** | **5 Years** | **10 Years** |
| **Class L Shares** |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp; Return Before Taxes | &nbsp;&nbsp;&nbsp;&nbsp; 6.41% | &nbsp;&nbsp;&nbsp;&nbsp; 4.57% | &nbsp;&nbsp;&nbsp;&nbsp; 6.71% |
| &nbsp;&nbsp;&nbsp;&nbsp; Return After Taxes on Distributions | &nbsp;&nbsp;&nbsp;&nbsp; 4.06% | &nbsp;&nbsp;&nbsp;&nbsp; 3.45% | &nbsp;&nbsp;&nbsp;&nbsp; 5.23% |
| &nbsp;&nbsp;&nbsp;&nbsp; Return After Taxes on Distributions and Sale of Fund Shares<sup>(1)</sup> <br>| &nbsp;&nbsp;&nbsp;&nbsp; 5.70% | &nbsp;&nbsp;&nbsp;&nbsp; 3.52% | &nbsp;&nbsp;&nbsp;&nbsp; 5.07% |
| &nbsp;&nbsp;&nbsp;&nbsp; Russell 3000<sup>®</sup> Index<br> (reflects no deduction for expenses, fees, or taxes)<br>| &nbsp;&nbsp;&nbsp;&nbsp; 23.81% | &nbsp;&nbsp;&nbsp;&nbsp; 13.86% | &nbsp;&nbsp;&nbsp;&nbsp; 12.55% |
| &nbsp;&nbsp;&nbsp;&nbsp; Russell 2000<sup>®</sup> Value Index<br> (reflects no deduction for expenses, fees, or taxes)<br>| &nbsp;&nbsp;&nbsp;&nbsp; 8.05% | &nbsp;&nbsp;&nbsp;&nbsp; 7.29% | &nbsp;&nbsp;&nbsp;&nbsp; 7.14% |

---

(1) If the Fund incurs a loss, which generates a tax benefit, the Return After Taxes on Distributions and Sale of Fund Shares may exceed the Fund's other return figures.

The Fund's broad-based benchmark index is the Russell 3000 Index, due to regulatory requirements. The Fund's additional benchmark index is the Russell 2000 Value Index, which has investment characteristics similar to those of the Fund. The indices are described below.

• The Russell 3000 Index measures the performance of the largest 3,000 U.S. companies.

• The Russell 2000 Value Index measures the performance of those Russell 2000 companies with lower price-to-book ratios and lower forecasted growth values.

After-tax returns are calculated using the historically highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-advantaged account, such as a 401(k) plan or an IRA.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Management**<br>

**Investment Adviser:** Janus Henderson Investors US LLC

**Portfolio Management: Craig Kempler**, CFA, is Executive Vice President and Co-Portfolio Manager of the Fund, which he has co-managed since October 2017. **Justin Tugman**, CFA, is Executive Vice President and Co-Portfolio Manager of the Fund, which he has co-managed since March 2009.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

4 \| Janus Investment Fund

------

**Purchase and sale of Fund shares**<br>

**Minimum Investment Requirements**

Class L Shares of the Fund are designed for pension and profit-sharing plans, employee benefit trusts, endowments, foundations and corporations, as well as high net worth individuals and financial intermediaries who are willing to maintain a minimum account balance of $250,000.

Purchases, exchanges, and redemptions can generally be made only through institutional channels, such as financial intermediaries and retirement platforms. You should contact your financial intermediary or refer to your plan documents for information on how to invest in the Fund. Requests must be received in good order by the Fund or its agents (financial intermediary or plan sponsor, if applicable) prior to the close of the trading session of the New York Stock Exchange in order to receive that day's net asset value. For additional information, refer to "Purchases," "Exchanges," and/or "Redemptions" in the Prospectus.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Tax information**<br>

The Fund's distributions are taxable, and will be taxed as ordinary income or capital gains, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or an individual retirement account (in which case you may be taxed upon withdrawal of your investment from such account).

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

**Payments to broker-dealers and other financial intermediaries**<br>

If you purchase the Fund through a broker-dealer or other financial intermediary (such as a bank), the Fund or its distributor (or its affiliates) 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 or to recommend one share class over another. Ask your salesperson or visit your financial intermediary's website for more information.

5 \| Janus Henderson Small Cap Value Fund

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