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Janus Henderson Global Real Estate Fund

Ticker: JNGSX Class D Shares*

* Effective July 6, 2020, Class D Shares are open to new investors. Until that time, Class D Shares remain closed to new investors, with certain limited exceptions.

Summary Prospectus dated January 28, 2020

As Supplemented February 20, 2020 and June 19, 2020

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.

Beginning on January 1, 2021, as permitted by regulations adopted by the Securities and Exchange Commission, paper copies of the Fund’s shareholder reports will no longer be sent by mail, unless you specifically request paper copies of the reports from the Fund or your plan sponsor, broker-dealer, or financial intermediary, or if you invest directly with the Fund, by contacting a Janus Henderson representative. Instead, the reports will be made available on a website, and you will be notified by mail each time a report is posted and provided with a website link to access the report.

If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the Fund electronically by contacting your plan sponsor, broker-dealer, or financial intermediary, or if you invest directly with the Fund, by visiting janushenderson.com/edelivery.

You may elect to receive all future reports in paper free of charge. If you do not invest directly with the Fund, you should contact your plan sponsor, broker-dealer, or financial intermediary, to request to continue receiving paper copies of your shareholder reports. If you invest directly with the Fund, you can call 1-800-525-3713 to let the Fund know that you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all Janus Henderson mutual funds where held (i.e., all Janus Henderson mutual funds held in your account if you invest through your financial intermediary or all Janus Henderson mutual funds held with the fund complex if you invest directly with a fund).

Investment Objective

Janus Henderson Global Real Estate Fund seeks total return through a combination of capital appreciation and current income.

Fees and Expenses of the Fund

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

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)	Class D
Management Fees(1)	0.85%
Other Expenses	0.31%
Acquired Fund(2) Fees and Expenses	0.01%
Total Annual Fund Operating Expenses	1.17%

(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.

(2)

“Acquired Fund” refers to any underlying fund (including, but not limited to, exchange-traded funds) in which a fund invests or has invested during the period. Acquired fund fees and expenses are indirect expenses a fund may incur as a result of investing in shares of an underlying fund. To the extent that the Fund invests in Acquired Funds, the Fund’s “Total Annual Fund Operating Expenses” may not correlate to the “Ratio of gross expenses to average net assets” presented in the Financial Highlights table because that ratio includes only the direct operating expenses incurred by the Fund, not the indirect costs of investing in Acquired Funds.

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

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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	$ 119	$ 372	$ 644	$ 1,420

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 61% of the average value of its portfolio.

Principal investment strategies

The Fund pursues its investment objective by investing, under normal circumstances, at least 80% of its net assets (plus any borrowings for investment purposes) in equity securities of real estate-related companies. Such companies may include those in the real estate industry or real estate-related industries. These securities may include common stocks, preferred stocks, and other equity securities, including, but not limited to, real estate investment trusts (“REITs”) and similar REIT-like entities, such as foreign entities that have REIT characteristics. The Fund may invest in shares of companies through initial public offerings.

As a fundamental policy, the Fund will concentrate 25% or more of its net assets in securities of issuers in real estate or real estate-related industries. The Fund’s investment in companies engaged in businesses outside the real estate industry which possess significant real estate holdings will be deemed to be in the real estate industry for purposes of the Fund’s investment objective and its policy on industry concentration.

Real estate-related industries are comprised of companies that, in the opinion of the portfolio managers, at the time of investment, generally (i) derive at least 50% of their revenue from ownership, construction, extraction, financing, management, operation, sales or development of real estate, or from businesses which have a clear relationship to these activities; (ii) have at least 50% of their assets in real estate; or (iii) have more than 50% of their net asset value accounted for by real estate.

A REIT is a company dedicated to owning, and usually operating, income-producing real estate, or to financing real estate. REITs pool investors’ funds for investment primarily in income-producing real estate or real estate-related loans or interests. Under the Internal Revenue Code of 1986, as amended (the “Internal Revenue Code”), a REIT is not taxed on income it distributes to its shareholders if it complies with several requirements relating to its organization, ownership, assets and income, and a requirement that it generally distributes to its shareholders at least 90% of its taxable income (other than net capital gains) for each taxable year.

The Fund also invests in non-U.S. real estate and real estate-related companies. The Fund expects under normal market conditions to maintain investments in issuers that are economically tied to different countries throughout the world, including the United States. The Fund may also invest in companies or issuers that are economically tied to emerging markets.

In choosing investments for the Fund, the portfolio managers apply a “bottom up” approach that utilizes the portfolio managers’ knowledge of issuers in the Americas and the Asia Pacific and European regions. The portfolio managers may also apply a “top down” analysis of property markets and sectors, economics, and capital markets in seeking to limit the Fund’s exposures to various risks.

The Fund may lend portfolio securities on a short-term or long-term basis, in an amount equal to up to one-third of its total assets as determined at the time of the loan origination.

Principal investment risks

The biggest risk is that the Fund’s returns will vary, and you could lose money. The Fund is designed for long-term investors interested in investments focused in the real estate industry or real estate-related industries, including common stocks. Common stocks tend to be more volatile than many other investment choices.

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Real Estate Securities Risk.  An investment in the Fund may be subject to many of the same risks as a direct investment in real estate. The value of real estate-related companies’ securities is sensitive to changes in real estate values and rental income, property taxes, interest rates, tax and regulatory requirements, supply and demand, and the management skill and creditworthiness of the company. Investments in REITs involve the same risks as other real estate investments. In addition, a REIT could fail to qualify for tax-free pass-through of its income under the Internal Revenue Code 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.

Concentration Risk.  Since the Fund concentrates its assets in the real estate or real estate-related industry, an investment in the Fund will be closely linked to performance of the real estate markets. As a result, the Fund may be subject to greater risks and its net asset value may fluctuate more than a fund that does not concentrate its investments.

Foreign Exposure Risk.  The Fund normally has significant exposure to foreign markets as a result of its investments in foreign securities, including investments in emerging markets, which can be more volatile than the U.S. markets. As a result, its returns and net asset value may be affected to a large degree by fluctuations in currency exchange rates or political or economic conditions in a particular country. 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. The Fund’s investments in emerging market countries may involve risks greater than, or in addition to, the risks of investing in more developed countries.

Market Risk.  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 or if the portfolio managers’ belief about a company’s intrinsic worth is incorrect. 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. 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. Market risk may affect a single issuer, industry, economic sector, or the market as a whole.

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. Although IPO investments may have had a positive impact on the Fund’s performance in the past, there can be no assurance that the Fund will identify favorable IPO investment opportunities in the future. In addition, as the Fund increases in size, the impact of IPOs on the Fund’s performance will generally decrease.

Emerging Markets Risk.  The risks of foreign investing are heightened when investing in emerging markets. Emerging markets securities involve a number of additional risks, which may result from less government supervision and regulation of business and industry practices (including the potential lack of strict finance and accounting controls and standards), stock exchanges, brokers, and listed companies, making these investments potentially more volatile in price and less liquid than investments in developed securities markets, resulting in greater risk to investors. There is a risk in developing countries that a future economic or political crisis could lead to price controls, forced mergers of companies, expropriation or confiscatory taxation, imposition or enforcement of foreign ownership limits, seizure, nationalization, sanctions or imposition of restrictions by various governmental entities on investment and trading, or creation of government monopolies, any of which may have a detrimental effect on the Fund’s investments. In addition, the Fund’s investments may be denominated in foreign currencies and therefore, changes in the value of a country’s currency compared to the U.S. dollar may affect the value of the Fund’s investments. To the extent that the Fund invests a significant portion of its assets in the securities of emerging markets issuers in or companies of a single country or region, it is more likely to be impacted by events or conditions affecting that country or region, which could have a negative impact on the Fund’s performance. As of September 30, 2019, approximately 5.6% of the Fund’s investments were in emerging markets (i.e., countries included in the MSCI Emerging Markets Index^sm).

Securities Lending Risk.  The Fund may seek to earn additional income through lending its securities to certain qualified broker-dealers and institutions. There is the risk that when portfolio securities are lent, the securities may not be returned on a timely basis, and the Fund may experience delays and costs in recovering the security or gaining access to the collateral provided to the Fund to collateralize the loan. If the Fund is unable to recover a security on loan, the Fund may use the

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collateral to purchase replacement securities in the market. There is a risk that the value of the collateral could decrease below the cost of the replacement security by the time the replacement investment is made, resulting in a loss to the Fund.

Management Risk.  The Fund is an actively managed investment portfolio and is therefore subject to the risk that the investment strategies employed for the Fund may fail to produce the intended results. The Fund may underperform its benchmark index or other mutual funds with similar investment objectives.

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.

Performance information

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. Class D Shares of the Fund commenced operations on February 16, 2010. The performance shown for Class D Shares for periods prior to February 16, 2010, reflects the performance of the Fund’s Class I Shares calculated using the fees and expenses of Class D Shares, without the effect of any fee and expense limitations or waivers. If Class D Shares of the Fund had been available during periods prior to February 16, 2010, the performance shown may have been different. The performance shown for the periods following the Fund’s commencement of Class D Shares reflects the fees and expenses of Class D Shares, net of any applicable fee and expense limitations or waivers.

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 broad-based securities market indices. 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.

Annual Total Returns for Class D Shares (calendar year-end)

Best Quarter: 1st Quarter 2012 16.13% Worst Quarter: 3rd Quarter 2011 – 20.37%

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Average Annual Total Returns (periods ended 12/31/19)
	1 Year	5 Years	10 Years	Since Inception of Predecessor Fund (11/28/07)
Class D Shares
Return Before Taxes	30.88%	8.56%	9.69%	5.78%
Return After Taxes on Distributions	28.77%	6.71%	8.26%	4.50%
Return After Taxes on Distributions and Sale of Fund Shares	18.53%	5.93%	7.33%	4.09%
FTSE EPRA Nareit Global Index (reflects no deduction for expenses, fees, or taxes)	23.58%	6.94%	8.91%	4.28%
FTSE EPRA Nareit Global Net Index (reflects no deduction for expenses, fees, or taxes, except foreign withholding taxes)	22.50%	6.03%	8.10%	N/A

The Fund’s primary benchmark index is the FTSE EPRA Nareit Global Index. The primary index is used to calculate the Fund’s performance fee adjustment. The Fund also compares its performance to the FTSE EPRA Nareit Global Net Index (the “Net Index”). Both indices are composed of the same holdings. However, the FTSE EPRA Nareit Global Index reflects no deduction for foreign withholding taxes, whereas the Net Index reflects deduction for such taxes. The indices are described below.

• The FTSE EPRA Nareit Global Index and the Net Index are global market capitalization-weighted indices composed of listed real estate securities in the North American, European, Asian, and South American real estate markets including both developed and emerging market countries.

After-tax returns are calculated using distributions for the Fund’s Class D Shares for the periods following February 16, 2010; and for the Fund’s Class I Shares for the periods prior to February 16, 2010. If Class D Shares of the Fund had been available during these earlier periods, distributions may have been different and thus, after-tax returns may have been different from those shown. 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.

Management

Investment Adviser:  Janus Capital Management LLC

Portfolio Managers: Guy Barnard, CFA, is Executive Vice President and Co-Portfolio Manager of the Fund, and has been a member of the Fund’s portfolio management team since June 2017.Tim Gibson is Executive Vice President and Co-Portfolio Manager of the Fund, and has been a member of the Fund’s portfolio management team since June 2017.Greg Kuhl, CFA, is Executive Vice President and Co-Portfolio Manager of the Fund, and has been a member of the Fund’s portfolio management team since March 2019.

Purchase and sale of Fund shares

Minimum Investment Requirements
To open a new regular Fund account	$2,500
To open a new regular Fund account with an automatic investment program of $50 per month	$ 100
To open a new UGMA/UTMA account, Coverdell Education Savings Account, or a retirement Fund account
• without an automatic investment program	$1,000
• 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, wire transfer, telephone, and in most cases, online at janushenderson.com/individual. You may conduct transactions by mail (Janus

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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 regular 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.

Tax information

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).

Payments to broker-dealers and other financial intermediaries

With respect to share classes not offered in this Prospectus, the Fund and its related companies 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.

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