JMBS Janus Henderson Mortgagebacked Securities ETF

The Fund pursues its investment objective by normally investing at least 80% of its net assets (plus any borrowings for investment purposes) in the securities that comprise the Janus Henderson Small Cap Growth Alpha Index (“Underlying Index”).

The Underlying Index is composed of common stocks of small-sized companies that are included in the Solactive Small Cap Index, a universe of 2,000 small-sized capitalization stocks. The Solactive Small Cap Index uses the total public market value, or “free-float,” capitalization of a stock to determine whether to include such stock in the Solactive Small Cap Index. The Underlying Index is designed to select small-sized capitalization stocks that are poised for “smart growth” by evaluating each company’s performance in three critical areas: growth, profitability, and capital efficiency. Using a proprietary quantitative methodology, such stocks are scored based on fundamental measures of their growth, profitability, and capital efficiency, and the top 10% of such eligible stocks scoring the highest become the constituents of the Underlying Index. To arrive at the top 10%, for each security in the stated universe, the quantitative methodology assigns a score in each of 10 different fundamental factors, relative to other eligible securities. The fundamental factors include measures that Janus Capital believes are tied to a

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stock’s outperformance relative to other small cap stocks, and indicate a company’s performance with respect to growth (such as the revenue growth rate over 2- 5- and 8- year periods), profitability (such as margin expansion, profit margin and earnings per share over time) and capital efficiency (such as returns on invested capital). The scores for each stock within a factor are then added together across the 10 factors, with equal weighting, to arrive at an overall score for each stock. The stocks with the highest 10% of scores are then weighted within the Underlying Index according to their market capitalization. Finally, the stocks are sector-weighted to reflect the sector allocation weight of Janus Henderson Venture Fund, based on its most recent publicly available holdings. A stock may not represent more than 3% of the Underlying Index. The Underlying Index seeks risk adjusted outperformance relative to a market capitalization weighted universe of small-sized capitalization growth stocks. Market capitalizations within the Underlying Index will vary, but as of February 1, 2020, they ranged from approximately $94 million to $3.3 billion. The Underlying Index is rebalanced on a quarterly basis based on the methodology described above.

The Fund uses a “passive,” index-based approach in seeking performance that corresponds to the performance of the Underlying Index. The Fund generally will use a replication methodology, meaning it will invest in the securities composing the Underlying Index in proportion to the weightings in the Underlying Index. However, the Fund may utilize a sampling methodology under various circumstances in which it may not be possible or practicable to purchase all of the securities in the Underlying Index. Janus Capital expects that over time, if the Fund has sufficient assets, the correlation between the Fund’s performance, before fees and expenses, and that of the Underlying Index will be 95% or better. A figure of 100% would indicate perfect correlation.

The Fund may also invest in investments that are not included in the Underlying Index, but which Janus Capital believes will help the Fund track the Underlying Index. Such investments include stocks, shares of other investment companies, cash and cash equivalents, including money market funds.

To the extent the Underlying Index concentrates (i.e., holds 25% or more of its total assets) in the securities of a particular industry or group of industries, the Fund will concentrate its investments to approximately the same extent as the Underlying Index. As of February 1, 2020, the Underlying Index did not concentrate in a particular industry or group of industries. For more recent information, see the Fund’s daily portfolio holdings posted on the ETF portion of the Janus Henderson website.

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.

The Underlying Index is compiled and administered by Janus Henderson Indices LLC (“JH Indices” or the “Index Provider”). JH Indices is affiliated with the Fund and Janus Capital.

The Fund’s Board of Trustees (“Trustees”) may change the Fund’s investment objective or non-fundamental principal investment strategies without a shareholder vote. The Fund will notify you in writing at least 60 days or as soon as reasonably practicable before making any such change it considers material. In addition, the Fund will provide shareholders with at least 60 days’ notice prior to changing the 80% investment policy. If there is a material change to the Fund’s objective or principal investment strategies, you should consider whether the Fund remains an appropriate investment for you. There is no guarantee that the Fund will achieve its investment objective.

The Fund’s portfolio holdings are disclosed on its website daily after the close of trading on the exchange and prior to the opening of trading on the exchange the following day. A description of the Fund’s policies and procedures with respect to the disclosure of the Fund’s portfolio holdings is available in the Fund’s SAI. Information about the premiums and discounts at which the Fund’s shares have traded is available at janushenderson.com/performance by selecting the Fund for additional details.

Unless otherwise stated, the following additional investment strategies and general policies apply to the Fund and provide further information including, but not limited to, the types of securities the Fund may invest in when implementing its investment objective. Some of these strategies and policies may be part of a principal strategy. Other strategies and policies may be utilized to a lesser extent. Except for the Fund’s policies with respect to investments in illiquid investments and borrowing, the percentage limitations included in these policies and elsewhere in this Prospectus and/or the SAI normally apply only at the time of purchase of a security. So, for example, if the Fund exceeds a limit as a result of market fluctuations or the sale of other securities, it will not be required to dispose of any securities and may continue to purchase such securities in order to track the Underlying Index.

Real Estate-Related Securities

Although not considered a principal investment strategy, the Fund may invest in equity securities of real estate-related companies to the extent such securities are included in the Underlying Index. 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, such as mortgage-backed securities, real estate-backed securities, securities of real estate investment trusts (“REITs”) and similar REIT-like entities. A REIT is a trust that invests in real estate-related projects, such as properties, mortgage loans, and construction loans. REITs are generally categorized as equity, mortgage, or hybrid REITs. A REIT may be listed on an exchange or traded over-the-counter.

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Securities Lending

Although not considered a principal investment strategy, the Fund may seek to earn additional income through lending its securities to certain qualified broker-dealers and institutions on a short-term or long-term basis. 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. When the Fund lends its securities, it receives collateral (including cash collateral), at least equal to the value of securities loaned. The Fund may earn income by investing this collateral in one or more affiliated or non-affiliated cash management vehicles. It is also possible that, due to a decline in the value of a cash management vehicle in which collateral is invested, the Fund may lose money. There is also 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 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. In certain circumstances, individual loan transactions could yield negative returns. To the extent Janus Capital manages the cash collateral in an affiliated cash management vehicle, it will receive an investment advisory fee for managing such assets.

Non-Index Investments

Although not considered a principal investment strategy, the Fund may invest in investments that are not included in the Underlying Index, but which Janus Capital believes will help the Fund track its Underlying Index. Such investments include common stocks, shares of other investment companies, and cash and cash equivalents, including money market funds. There may be instances where a stock is removed from the Underlying Index but Janus Capital may elect to hold it for tax-related purposes, or where the Fund receives non-Underlying Index stocks in a corporate action and does not sell the stocks until the next rebalance date. Janus Capital may also choose to hold non-Underlying Index stocks due to an optimization methodology to more efficiently track the Underlying Index. Use of an optimization methodology would entail the use of a program or model designed to identify securities that are not included in the Underlying Index, but would be expected to behave similarly to securities that are in the Underlying Index.

The value of your investment will vary over time, sometimes significantly, and you may lose money by investing in the Fund. The Fund invests substantially all of its assets in small-sized capitalization stocks. The following information is intended to help you better understand some of the risks of investing in the Fund. The impact of the following risks on the Fund may vary depending on the Fund’s investments. The greater the Fund’s investment in a particular security, the greater the Fund’s exposure to the risks associated with that security. Before investing in the Fund, you should consider carefully the risks that you assume when investing in the Fund.

Index Tracking Risk.  Tracking error refers to the risk that Janus Capital may not be able to cause the Fund’s performance to match or correlate to that of the Underlying Index, either on a daily or aggregate basis. There are a number of factors that may contribute to the Fund’s tracking error, such as Fund expenses, imperfect correlation between the Fund’s investments and those of the Underlying Index, rounding of share prices, the timing or magnitude of changes to the composition of the Underlying Index, regulatory policies, and a high portfolio turnover rate. The Fund incurs operating expenses not applicable to the Underlying Index and incurs costs associated with buying and selling securities, especially when rebalancing the Fund’s securities holdings to reflect changes in the composition of the Underlying Index. In addition, mathematical compounding may prevent the Fund from correlating with the monthly, quarterly, annual, or other period performance of the Underlying Index. Tracking error may cause the Fund’s performance to be less than expected.

Passive Investment Risk.  The Fund is not actively managed. Therefore, unless a specific security is removed from the Underlying Index, or the selling of shares of that security is otherwise required upon a rebalancing of the Underlying Index pursuant to the Underlying Index methodology, the Fund generally would not sell a security because the security’s issuer was in financial trouble. If a specific security is removed from the Underlying Index, the Fund may be forced to sell such security at an inopportune time or for a price other than the security’s current market value. An investment in the Fund involves risks similar to those of investing in equity securities traded on an exchange, such as market fluctuations caused by such factors as economic and political developments, changes in interest rates and perceived trends in security prices. It is anticipated that the value of Fund shares will decline, more or less, in correspondence with any decline in value of the Underlying Index.

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The Underlying Index may not contain the appropriate mix of securities for any particular point in the business cycle of the overall economy, particular economic sectors, or narrow industries within which the commercial activities of the companies composing the portfolio securities holdings of the Fund are conducted, and the timing of movements from one type of security to another in seeking to replicate the Underlying Index could have a negative effect on the Fund. Unlike with an actively managed fund, Janus Capital does not use techniques or defensive strategies designed to lessen the effects of market volatility or to reduce the impact of periods of market decline. This means that, based on market and economic conditions, the Fund’s performance could be lower than other types of mutual funds that may actively shift their portfolio assets to take advantage of market opportunities or to lessen the impact of a market decline.

Affiliated Index Provider Risk.  JH Indices, the index provider for the Fund, is an affiliated person of Janus Capital, which poses the appearance of a conflict of interest. For example, a potential conflict could arise between an affiliated person of Janus Capital and the Fund if that entity attempted to use information regarding changes and composition of the Underlying Index to the detriment of the Fund. Additionally, potential conflicts could arise with respect to the personal trading activity of personnel of the affiliated person who may have access to, or knowledge of, pending changes to the Underlying Index’s composition methodology or the constituent securities in the Underlying Index prior to the time that information is publicly disseminated. If shared, such knowledge could facilitate “front-running” (which describes an instance in which other persons trade ahead of a Fund). Although Janus Capital and JH Indices have taken steps designed to ensure that these potential conflicts are mitigated (e.g., via the adoption of policies and procedures that are designed to minimize potential conflicts of interest and the implementation of informational barriers designed to minimize the potential for the misuse of information about the Underlying Index), there can be no assurance that such measures will be successful.

Fluctuation of NAV.  The NAV of the Fund shares will generally fluctuate with changes in the market value of the Fund’s securities holdings. The market prices of shares will generally fluctuate in accordance with changes in the Fund’s NAV and supply and demand of shares on the NASDAQ. It cannot be predicted whether Fund shares will trade below, at or above their NAV. Price differences may be due, in large part, to the fact that supply and demand forces at work in the secondary trading market for shares will be closely related to, but not identical to, the same forces influencing the prices of the securities of the Underlying Index trading individually or in the aggregate at any point in time. In addition, during periods of significant volatility, the liquidity of the underlying securities held by the Fund may affect the Fund’s trading prices. While the creation/redemption feature is designed to make it likely that Fund shares normally will trade close to the Fund’s NAV, disruptions to creations and redemptions may result in trading prices that differ significantly from the Fund’s NAV. An absence of trading in shares of the Fund, or a high volume of trading in the Fund, may result in trading prices that differ significantly from the Fund’s NAV. If an investor purchases Fund shares at a time when the market price is at a premium to the NAV of the shares or sells at a time when the market price is at a discount to the NAV of the shares, then the investor may sustain losses. Further, the securities held by the Fund may be traded in markets that close at a different time than the NASDAQ. Liquidity in those securities may be reduced after the applicable closing times. Accordingly, during the time when the NASDAQ is open but after the applicable market closing, bid-ask spreads and the resulting premium or discount to the Fund shares’ NAV may widen. Similarly, the NASDAQ may be closed at times or days when markets for securities held by the Fund are open, which may increase bid-ask spreads and the resulting premium or discount to the Fund shares’ NAV when the NASDAQ re-opens.

Transaction and Spread Risk.  Investors buying or selling Fund shares in the secondary market will pay brokerage commissions or other charges imposed by brokers as determined by that broker. Brokerage commissions are often a fixed amount and may be a significant proportional cost for investors seeking to buy or sell relatively small amounts of shares. In addition, secondary market investors will also incur the cost of the difference between the price that an investor is willing to pay for shares (the “bid” price) and the price at which an investor is willing to sell shares (the “ask” price). This difference in bid and ask prices is often referred to as the “spread” or “bid/ask spread.” The bid/ask spread varies over time for shares based on trading volume and market liquidity, and is generally lower if the Fund’s shares have more trading volume and market liquidity and higher if the Fund’s shares have little trading volume and market liquidity. Further, increased market volatility and trading halts affecting any of the Fund’s portfolio securities may cause increased bid/ask spreads. Due to the costs of buying or selling shares, including bid/ask spreads, frequent trading of shares may significantly reduce investment results and an investment in shares may not be advisable for investors who anticipate regularly making small investments.

Trading Issues Risk.  Trading in shares on the NASDAQ may be halted due to market conditions or for reasons that, in the view of the NASDAQ, make trading in shares inadvisable. In addition, trading in shares on the NASDAQ is subject to trading halts caused by extraordinary market volatility pursuant to the NASDAQ “circuit breaker” rules. There can be no assurance that the requirements of the NASDAQ necessary to maintain the listing of the Fund will continue to be met or will remain unchanged or

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that the shares will trade with any volume, or at all. While the creation/redemption feature is designed to make it likely that shares will trade close to the Fund’s NAV, disruptions to creations and redemptions may result in trading prices that differ significantly from the Fund’s NAV. If an investor purchases shares at a time when the market price is at a premium to the NAV of the shares or sells at a time when the market price is at a discount to the NAV of the shares, then the investor may sustain losses. In addition, during periods of significant volatility, the liquidity of the underlying securities held by the Fund may affect the Fund’s trading prices. For example, when the Fund’s underlying securities trade on foreign exchanges that are closed when the securities exchange on which the Fund’s shares trade is open, this may result in deviations between the current price of such an underlying security and the last quoted price for the underlying security. This could result in premiums or discounts to the Fund’s NAV. During a “flash crash,” the market prices of the Fund’s shares may decline suddenly and significantly. Such a decline may not reflect the performance of the portfolio securities held by the Fund. Flash crashes may cause Authorized Participants and other market makers to limit or cease trading in the Fund’s shares for temporary or longer periods. Shareholders could suffer significant losses to the extent that they sell shares at these temporarily low market prices.

Real Estate Securities Risk.  Although not considered a principal risk, the Fund’s performance may be affected by the risks associated with investments in real estate-related companies. 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 (“1940 Act”), which could produce adverse economic consequences for the REIT and its investors, including the Fund.

These risks are described further in the SAI.

The Underlying Index is composed of common stocks from a universe of 2,000 small-sized capitalization stocks. The Solactive Small Cap Index uses the total public market value, or “free-float,” capitalization of a stock to determine whether to include such stock in the Solactive Small Cap Index. The Underlying Index is designed to select small-sized capitalization stocks that are poised for “smart growth” by evaluating each company’s performance in three critical areas: growth, profitability, and capital efficiency. Using a proprietary quantitative methodology, such stocks are scored based on fundamental measures of their growth, profitability, and capital efficiency, and the top 10% of such eligible stocks scoring the highest become the constituents of the Underlying Index. To arrive at the top 10%, for each security in the stated universe, the quantitative methodology assigns a score in each of 10 different factors, relative to other eligible securities. The fundamental factors include measures that Janus Capital believes are tied to a stock’s outperformance relative to other small cap stocks, and indicate a company’s performance with respect to growth (such as the revenue growth rate over 2- 5- and 8- year periods), profitability (such as margin expansion, profit margin and earnings per share over time) and capital efficiency (such as returns on invested capital). Each stock in the eligible universe will receive a point total equal to the decile rank of the stock for a given factor. For example, if a stock is in the top decile for a given factor, it will receive 10 points for that factor. If the stock is in the lowest decile, it will receive 1 point. For each factor, a threshold is established, and to the extent a stock’s score within a factor meets or exceeds the threshold, it will receive additional points. A high threshold means that exceeding that threshold is relatively difficult for a stock to achieve, and as a result will receive more bonus points than if the threshold were lower. For detailed information on how stocks are scored, see the Janus Henderson Small Cap Growth Alpha Index Methodology document, available at the Index Provider’s website.

The scores for each stock within a factor are then added together across the 10 factors, with equal weighting, to arrive at an overall score for each stock. These stocks with the highest 10% of scores are then weighted within the Underlying Index according to their market capitalization. Finally, the stocks are sector-weighted to reflect the sector allocation weight of Janus Henderson Venture Fund, based on its most recent publicly available holdings. A stock may not represent more than 3% of the Underlying Index. The Underlying Index seeks risk adjusted outperformance relative to a market capitalization weighted universe of small-sized capitalization growth stocks. Market capitalizations within the Underlying Index will vary, but as of February 1, 2020, they ranged from approximately $94 million to $3.3 billion. From time to time, and often as the result of specific corporate actions, the Solactive Small Cap Index (and as a result the Underlying Index) may temporarily include companies that are either smaller or larger than are typically considered to be small-capitalization. The Underlying Index is rebalanced on a quarterly basis based on the methodology described above.

The Underlying Index is compiled and administered by JH Indices, an affiliate of the Fund and Janus Capital.

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The Fund pursues its investment objective by normally investing at least 80% of its net assets (plus any borrowings for investment purposes) in the securities that comprise the Janus Henderson Small/Mid Cap Growth Alpha Index (“Underlying Index”).

The Underlying Index is composed of common stocks of small- and medium-sized companies that are included in the Solactive Small/Mid Cap Index, a universe of 2,500 small- and medium-sized capitalization stocks. The Solactive Small/Mid Cap Index uses the total public market value, or “free-float,” capitalization of a stock to determine whether to include such stock in the Solactive Small/Mid Cap Index. The Underlying Index is designed to select small- and medium-sized capitalization stocks that are poised for “smart growth” by evaluating each company’s performance in three critical areas: growth, profitability, and capital efficiency. Using a proprietary quantitative methodology, such stocks are scored based on fundamental measures of their growth, profitability, and capital efficiency, and the top 10% of such eligible stocks scoring the highest become the constituents of the Underlying Index . To arrive at the top 10%, for each security in the stated universe, the quantitative methodology assigns a score in each of 10 different fundamental factors, relative to other eligible securities. The fundamental factors include measures

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that Janus Capital believes are tied to a stock’s outperformance relative to other small/mid cap stocks, and indicate a company’s performance with respect to growth (such as the revenue growth rate over 2- 5- and 8- year periods), profitability (such as margin expansion, profit margin and earnings per share over time) and capital efficiency (such as returns on invested capital). The scores for each stock within a factor are then added together across the 10 factors, with equal weighting, to arrive at an overall score for each stock. The stocks with the highest 10% of scores are then weighted within the Underlying Index according to their market capitalization. Finally, the stocks are sector-weighted to reflect the sector allocation weight of Janus Henderson Triton Fund, based on its most recent publicly available holdings. A stock may not represent more than 3% of the Underlying Index. The Underlying Index seeks risk adjusted outperformance relative to a market capitalization weighted universe of small- and medium-sized capitalization growth stocks. Market capitalizations within the Underlying Index will vary, but as of February 1, 2020, they ranged from approximately $94 million to $63.8 billion. The Underlying Index is rebalanced on a quarterly basis based on the methodology described above.

The Fund uses a “passive,” index-based approach in seeking performance that corresponds to the performance of the Underlying Index. The Fund generally will use a replication methodology, meaning it will invest in the securities composing the Underlying Index, in proportion to the weightings in the Underlying Index. However, the Fund may utilize a sampling methodology under various circumstances in which it may not be possible or practicable to purchase all of the securities in the Underlying Index. Janus Capital expects that over time, if the Fund has sufficient assets, the correlation between the Fund’s performance, before fees and expenses, and that of the Underlying Index will be 95% or better. A figure of 100% would indicate perfect correlation.

The Fund may also invest in investments that are not included in the Underlying Index, but which Janus Capital believes will help the Fund track the Underlying Index. Such investments include stocks, shares of other investment companies, cash and cash equivalents, including money market funds.

To the extent the Underlying Index concentrates (i.e., holds 25% or more of its total assets) in the securities of a particular industry or group of industries, the Fund will concentrate its investments to approximately the same extent as its Underlying Index. As of February 1, 2020, the Underlying Index did not concentrate in a particular industry or group of industries. For more recent information, see the Fund’s daily portfolio holdings posted on the ETF portion of the Janus Henderson website.

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.

The Underlying Index is compiled and administered by Janus Henderson Indices LLC (“JH Indices” or the “Index Provider”). JH Indices is affiliated with the Fund and Janus Capital.

The Fund’s Board of Trustees (“Trustees”) may change the Fund’s investment objective or non-fundamental principal investment strategies without a shareholder vote. The Fund will notify you in writing at least 60 days or as soon as reasonably practicable before making any such change it considers material. In addition, the Fund will provide shareholders with at least 60 days’ notice prior to changing the 80% investment policy. If there is a material change to the Fund’s objective or principal investment strategies, you should consider whether the Fund remains an appropriate investment for you. There is no guarantee that the Fund will achieve its investment objective.

The Fund’s portfolio holdings are disclosed on its website daily after the close of trading on the exchange and prior to the opening of trading on the exchange the following day. A description of the Fund’s policies and procedures with respect to the disclosure of the Fund’s portfolio holdings is available in the Fund’s SAI. Information about the premiums and discounts at which the Fund’s shares have traded is available at janushenderson.com/performance by selecting the Fund for additional details.

Unless otherwise stated, the following additional investment strategies and general policies apply to the Fund and provide further information including, but not limited to, the types of securities the Fund may invest in when implementing its investment objective. Some of these strategies and policies may be part of a principal strategy. Other strategies and policies may be utilized to a lesser extent. Except for the Fund’s policies with respect to investments in illiquid investments and borrowing, the percentage limitations included in these policies and elsewhere in this Prospectus and/or the SAI normally apply only at the time of purchase of a security. So, for example, if the Fund exceeds a limit as a result of market fluctuations or the sale of other securities, it will not be required to dispose of any securities and may continue to purchase such securities in order to track the Underlying Index.

Real Estate-Related Securities

Although not considered a principal investment strategy, the Fund may invest in equity securities of real estate-related companies to the extent such securities are included in the Underlying Index. 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, such as mortgage-backed securities, real estate-backed securities, securities of real estate investment trusts (“REITs”) and similar REIT-like entities. A REIT is a trust that invests in real estate-related projects, such as properties, mortgage loans, and construction loans. REITs are generally categorized as equity, mortgage, or hybrid REITs. A REIT may be listed on an exchange or traded over-the-counter.

Securities Lending

Although not considered a principal investment strategy, the Fund may seek to earn additional income through lending its securities to certain qualified broker-dealers and institutions on a short-term or long-term basis. The Fund may lend portfolio

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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. When the Fund lends its securities, it receives collateral (including cash collateral), at least equal to the value of securities loaned. The Fund may earn income by investing this collateral in one or more affiliated or non-affiliated cash management vehicles. It is also possible that, due to a decline in the value of a cash management vehicle in which collateral is invested, the Fund may lose money. There is also 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 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. To the extent Janus Capital manages the cash collateral in an affiliated cash management vehicle, it will receive an investment advisory fee for managing such assets.

Non-Index Investments

Although not considered a principal investment strategy, the Fund may invest in investments that are not included in the Underlying Index, but which Janus Capital believes will help the Fund track its Underlying Index. Such investments include common stocks, shares of other investment companies and cash and cash equivalents, including money market funds. There may be instances where a stock is removed from the Underlying Index but Janus Capital may elect to hold it for tax-related purposes, or where the Fund receives non-Underlying Index stocks in a corporate action and does not sell the stocks until the next rebalance date. Janus Capital may also choose to hold non-Underlying Index stocks due to an optimization methodology to more efficiently track the Underlying Index. Use of an optimization methodology would entail the use of a program or model designed to identify securities that are not included in the Underlying Index, but would be expected to behave similarly to securities that are in the Underlying Index.

The value of your investment will vary over time, sometimes significantly, and you may lose money by investing in the Fund. The Fund invests substantially all of its assets in small- and medium-sized capitalization stocks. The following information is intended to help you better understand some of the risks of investing in the Fund. The impact of the following risks on the Fund may vary depending on the Fund’s investments. The greater the Fund’s investment in a particular security, the greater the Fund’s exposure to the risks associated with that security. Before investing in the Fund, you should consider carefully the risks that you assume when investing in the Fund.

Index Tracking Risk.  Tracking error refers to the risk that Janus Capital may not be able to cause the Fund’s performance to match or correlate to that of the Underlying Index, either on a daily or aggregate basis. There are a number of factors that may contribute to the Fund’s tracking error, such as Fund expenses, imperfect correlation between the Fund’s investments and those of the Underlying Index, rounding of share prices, the timing or magnitude of changes to the composition of the Underlying Index, regulatory policies, and a high portfolio turnover rate. The Fund incurs operating expenses not applicable to the Underlying Index and incurs costs associated with buying and selling securities, especially when rebalancing the Fund’s securities holdings to reflect changes in the composition of the Underlying Index. In addition, mathematical compounding may prevent the Fund from correlating with the monthly, quarterly, annual, or other period performance of the Underlying Index. Tracking error may cause the Fund’s performance to be less than expected.

Passive Investment Risk.  The Fund is not actively managed. Therefore, unless a specific security is removed from the Underlying Index, or the selling of shares of that security is otherwise required upon a rebalancing of the Underlying Index pursuant to the Underlying Index methodology, the Fund generally would not sell a security because the security’s issuer was in financial trouble. If a specific security is removed from the Underlying Index, the Fund may be forced to sell such security at an inopportune time or for a price other than the security’s current market value. An investment in the Fund involves risks similar to those of investing in equity securities traded on an exchange, such as market fluctuations caused by such factors as economic and political developments, changes in interest rates and perceived trends in security prices. It is anticipated that the value of Fund shares will decline, more or less, in correspondence with any decline in value of the Underlying Index.

The Underlying Index may not contain the appropriate mix of securities for any particular point in the business cycle of the overall economy, particular economic sectors, or narrow industries within which the commercial activities of the companies composing the portfolio securities holdings of the Fund are conducted, and the timing of movements from one type of security to another in seeking to replicate the Underlying Index could have a negative effect on the Fund. Unlike with an actively

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managed fund, Janus Capital does not use techniques or defensive strategies designed to lessen the effects of market volatility or to reduce the impact of periods of market decline. This means that, based on market and economic conditions, the Fund’s performance could be lower than other types of mutual funds that may actively shift their portfolio assets to take advantage of market opportunities or to lessen the impact of a market decline.

Affiliated Index Provider Risk.  JH Indices, the index provider for the Fund, is an affiliated person of Janus Capital, which poses the appearance of a conflict of interest. For example, a potential conflict could arise between an affiliated person of Janus Capital and the Fund if that entity attempted to use information regarding changes and composition of the Underlying Index to the detriment of the Fund. Additionally, potential conflicts could arise with respect to the personal trading activity of personnel of the affiliated person who may have access to, or knowledge of, pending changes to the Underlying Index’s composition methodology or the constituent securities in the Underlying Index prior to the time that information is publicly disseminated. If shared, such knowledge could facilitate “front-running” (which describes an instance in which other persons trade ahead of a Fund). Although Janus Capital and JH Indices have taken steps designed to ensure that these potential conflicts are mitigated (e.g., via the adoption of policies and procedures that are designed to minimize potential conflicts of interest and the implementation of informational barriers designed to minimize the potential for the misuse of information about the Underlying Index), there can be no assurance that such measures will be successful.

Fluctuation of NAV.  The NAV of the Fund shares will generally fluctuate with changes in the market value of the Fund’s securities holdings. The market prices of shares will generally fluctuate in accordance with changes in the Fund’s NAV and supply and demand of shares on the NASDAQ. It cannot be predicted whether Fund shares will trade below, at or above their NAV. Price differences may be due, in large part, to the fact that supply and demand forces at work in the secondary trading market for shares will be closely related to, but not identical to, the same forces influencing the prices of the securities of the Underlying Index trading individually or in the aggregate at any point in time. In addition, during periods of significant volatility, the liquidity of the underlying securities held by the Fund may affect the Fund’s trading prices. While the creation/redemption feature is designed to make it likely that Fund shares normally will trade close to the Fund’s NAV, disruptions to creations and redemptions may result in trading prices that differ significantly from the Fund’s NAV. An absence of trading in shares of the Fund, or a high volume of trading in the Fund, may result in trading prices that differ significantly from the Fund’s NAV. If an investor purchases Fund shares at a time when the market price is at a premium to the NAV of the shares or sells at a time when the market price is at a discount to the NAV of the shares, then the investor may sustain losses. Further, the securities held by the Fund may be traded in markets that close at a different time than the NASDAQ. Liquidity in those securities may be reduced after the applicable closing times. Accordingly, during the time when the NASDAQ is open but after the applicable market closing, bid-ask spreads and the resulting premium or discount to the Fund shares’ NAV may widen. Similarly, the NASDAQ may be closed at times or days when markets for securities held by the Fund are open, which may increase bid-ask spreads and the resulting premium or discount to the Fund shares’ NAV when the NASDAQ re-opens.

Transaction and Spread Risk.  Investors buying or selling Fund shares in the secondary market will pay brokerage commissions or other charges imposed by brokers as determined by that broker. Brokerage commissions are often a fixed amount and may be a significant proportional cost for investors seeking to buy or sell relatively small amounts of shares. In addition, secondary market investors will also incur the cost of the difference between the price that an investor is willing to pay for shares (the “bid” price) and the price at which an investor is willing to sell shares (the “ask” price). This difference in bid and ask prices is often referred to as the “spread” or “bid/ask spread.” The bid/ask spread varies over time for shares based on trading volume and market liquidity, and is generally lower if the Fund’s shares have more trading volume and market liquidity and higher if the Fund’s shares have little trading volume and market liquidity. Further, increased market volatility and trading halts affecting any of the Fund’s portfolio securities may cause increased bid/ask spreads. Due to the costs of buying or selling shares, including bid/ask spreads, frequent trading of shares may significantly reduce investment results and an investment in shares may not be advisable for investors who anticipate regularly making small investments.

Trading Issues Risk.  Trading in shares on the NASDAQ may be halted due to market conditions or for reasons that, in the view of the NASDAQ, make trading in shares inadvisable. In addition, trading in shares on the NASDAQ is subject to trading halts caused by extraordinary market volatility pursuant to the NASDAQ “circuit breaker” rules. There can be no assurance that the requirements of the NASDAQ necessary to maintain the listing of the Fund will continue to be met or will remain unchanged or that the shares will trade with any volume, or at all. While the creation/redemption feature is designed to make it likely that shares will trade close to the Fund’s NAV, disruptions to creations and redemptions may result in trading prices that differ significantly from the Fund’s NAV. If an investor purchases shares at a time when the market price is at a premium to the NAV of the shares or sells at a time when the market price is at a discount to the NAV of the shares, then the investor may sustain

10_½Janus Detroit Street Trust

losses. In addition, during periods of significant volatility, the liquidity of the underlying securities held by the Fund may affect the Fund’s trading prices. For example, when the Fund’s underlying securities trade on foreign exchanges that are closed when the securities exchange on which the Fund’s shares trade is open, this may result in deviations between the current price of such an underlying security and the last quoted price for the underlying security. This could result in premiums or discounts to the Fund’s NAV. During a “flash crash,” the market prices of the Fund’s shares may decline suddenly and significantly. Such a decline may not reflect the performance of the portfolio securities held by the Fund. Flash crashes may cause Authorized Participants and other market makers to limit or cease trading in the Fund’s shares for temporary or longer periods. Shareholders could suffer significant losses to the extent that they sell shares at these temporarily low market prices.

Real Estate Securities Risk.  Although not considered a principal risk, the Fund’s performance may be affected by the risks associated with investments in real estate-related companies. 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 (“1940 Act”), which could produce adverse economic consequences for the REIT and its investors, including the Fund.

These risks are described further in the SAI.

The Underlying Index is composed of common stocks from a universe of 2,500 small-and medium-sized capitalization stocks. The Solactive Small/Mid Cap Index uses the total public market value, or “free-float,” capitalization of a stock to determine whether to include such stock in the Solactive Small/Mid Cap Index. The Underlying Index is designed to select small- and medium-sized capitalization stocks that are poised for “smart growth” by evaluating each company’s performance in three critical areas: growth, profitability, and capital efficiency. Using a proprietary quantitative methodology, such stocks are scored based on fundamental measures of their growth, profitability, and capital efficiency, and the top 10% of such eligible stocks scoring the highest become the constituents of the Underlying Index. To arrive at the top 10%, for each security in the stated universe, the quantitative methodology assigns a score in each of 10 different factors, relative to other eligible securities. The fundamental factors include measures that Janus Capital believes are tied to a stock’s outperformance relative to other small/mid cap stocks, and indicate a company’s performance with respect to growth (such as the revenue growth rate over 2- 5- and 8- year periods), profitability (such as margin expansion, profit margin and earnings per share over time) and capital efficiency (such as returns on invested capital). Each stock in the eligible universe will receive a point total equal to the decile rank of the stock for a given factor. For example, if a stock is in the top decile for a given factor, it will receive 10 points for that factor. If the stock is in the lowest decile, it will receive 1 point. For each factor, a threshold is established, and to the extent a stock’s score within a factor meets or exceeds the threshold, it will receive additional points. A high threshold means that exceeding that threshold is relatively difficult for a stock to achieve, and as a result will receive more bonus points than if the threshold were lower. For detailed information on how stocks are scored, see the Janus Henderson Small/Mid Cap Growth Alpha Index Methodology document, available at the Index Provider’s website.

The scores for each stock within a factor are then added together across the 10 factors, with equal weighting, to arrive at an overall score for each stock. These stocks with the highest 10% of scores are then weighted within the Underlying Index according to their market capitalization. Finally, the stocks are sector-weighted to reflect the sector allocation weight of Janus Henderson Triton Fund, based on its most recent publicly available holdings. A stock may not represent more than 3% of the Underlying Index. The Underlying Index seeks risk adjusted outperformance relative to a market capitalization weighted universe of small- and medium-sized capitalization growth stocks. Market capitalizations within the Underlying Index will vary, but as of February 1, 2020, they ranged from approximately $94 million to $63.8 billion. From time to time, and often as the result of specific corporate actions, the Solactive Small/Mid Cap Index (and as a result the Underlying Index) may temporarily include companies that are either smaller or larger than are typically considered to be small- and/or mid-sized capitalization. The Underlying Index is rebalanced on a quarterly basis based the methodology described above.

The Underlying Index is compiled and administered by JH Indices, an affiliate of the Fund and Janus Capital.

11_½Janus Detroit Street Trust

The Fund pursues its investment objective by investing at least 80% of its net assets (plus any borrowings for investment purposes) in the stocks that comprise the Solactive Obesity Index (“Underlying Index”). The Underlying Index is designed to track the performance of companies globally that are positioned to profit from servicing the obese, including biotechnology, pharmaceutical, health care and medical device companies whose business is focused on obesity and obesity related disease including diabetes, high blood pressure, cholesterol, heart disease, stroke, and sleep apnea, and companies focused on weight loss programs, weight loss supplements, or plus sized apparel. Under normal circumstances, the Fund expects to invest substantially all of its assets in securities included in the Underlying Index, using a replication strategy as discussed below. The Fund may invest in companies of any capitalization, although at least 90% of the companies will have a capitalization of at least $100 million. The Fund may invest in foreign issuers, including emerging markets. Stocks included in the Underlying Index may include common shares traded on local exchanges, American Depositary Receipts (“ADRs”) and Global Depositary Receipts (“GDRs”). ADRs and GDRs represent

2_½The Obesity ETF

ownership interests in shares of foreign companies that are held in financial institution custodial accounts, and are traded on exchanges in the United States and around the world.

The Fund is classified as nondiversified, which allows it to hold larger positions in a smaller number of companies, compared to a fund that is classified as diversified.

The Underlying Index, the Solactive Obesity Index, was created by and is maintained by Solactive AG (“Solactive” or the “Index Provider”). The Underlying Index is reconstituted on a semi-annual basis, rebalanced on a quarterly basis, and the Fund is rebalanced quarterly based on changes to the Underlying Index. The Fund uses a “passive,” index-based approach in seeking performance that corresponds to the performance of the Underlying Index. The underlying securities are weighted according to their market capitalization relative to other securities in the Underlying Index, and capped so that no security will represent more than 20% of the Underlying Index at the time of an index reconstitution or rebalance. Due to market movement between rebalancing and reconstitution of the Underlying Index, an underlying security may represent more than 20% of the Underlying Index at any given time, and thus may represent more than 20% of the Fund’s assets at any given time.

The Fund will generally use a replication methodology, meaning it will invest in the securities composing the Underlying Index in proportion to the weightings in the Underlying Index. However, the Fund may utilize a sampling methodology under various circumstances in which it may not be possible or practicable to purchase all of the securities in the Underlying Index. Janus Capital expects that over time, if the Fund has sufficient assets, the correlation between the Fund’s performance, before fees and expenses, and that of the Underlying Index will be 95% or better. A figure of 100% would indicate perfect correlation.

Under normal circumstances, the Fund expects to invest substantially all of its assets in securities included in the Underlying Index, although it may invest up to 20% its assets in other securities that Janus Capital believes will help the Fund track the Underlying Index. Such investments include stocks, shares of other investment companies, cash and cash equivalents, including money market funds.

To the extent the Underlying Index concentrates (i.e., holds 25% or more of its total assets) in the securities of a particular industry or group of industries, the Fund will concentrate its investments to approximately the same extent as the Underlying Index. As of February 1, 2020, approximately 64% of the Underlying Index was represented by companies in the Health Care Equipment & Services Industry. For more recent information, see the Fund’s daily portfolio holdings posted on the ETF portion of the Janus Henderson website.

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.

The Fund’s Board of Trustees (“Trustees”) may change the Fund’s investment objective or non-fundamental principal investment strategies without a shareholder vote. The Fund will notify you in writing at least 60 days or as soon as reasonably practicable before making any such change it considers material. In addition, the Fund will provide shareholders with at least 60 days’ notice prior to changing the 80% investment policy. If there is a material change to the Fund’s objective or principal investment strategies, you should consider whether the Fund remains an appropriate investment for you. There is no guarantee that the Fund will achieve its investment objective.

The Fund’s portfolio holdings are disclosed on its website daily after the close of trading on the exchange and prior to the opening of trading on the exchange the following day. A description of the Fund’s policies and procedures with respect to the disclosure of the Fund’s portfolio holdings is available in the Fund’s SAI. Information about the premiums and discounts at which the Fund’s shares have traded is available at janushenderson.com/performance by selecting the Fund for additional details.

Unless otherwise stated, the following additional investment strategies and general policies apply to the Fund and provide further information including, but not limited to, the types of securities the Fund may invest in when implementing its investment objective. Some of these strategies and policies may be part of a principal strategy. Other strategies and policies may be utilized to a lesser extent. Except for the Fund’s policies with respect to investments in illiquid investments and borrowing, the percentage limitations included in these policies and elsewhere in this Prospectus and/or the SAI normally apply only at the time of initial purchase of a security. So, for example, if the Fund exceeds a limit as a result of market fluctuations or the sale of other securities, it will not be required to dispose of any securities and may continue to purchase such securities in order to track the Underlying Index.

Securities Lending

Although not considered a principal investment strategy, the Fund may seek to earn additional income through lending its securities to certain qualified broker-dealers and institutions on a short-term or long-term basis. 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. When the Fund lends its securities, it receives collateral (including cash collateral), at least equal to the value of securities loaned. The Fund may earn income by investing this collateral in one or more affiliated or non-affiliated cash management vehicles. It is also possible that, due to a decline in the value of a cash management vehicle in which collateral is invested, the Fund may lose money. There is also 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 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. In

8_½Janus Detroit Street Trust

certain circumstances, individual loan transactions could yield negative returns. To the extent Janus Capital manages the cash collateral in an affiliated cash management vehicle, it will receive an investment advisory fee for managing such assets.

Swaps

Although not considered a principal investment strategy, the Fund may utilize swap agreements including, but not limited to, equity swaps, as a means to gain exposure to certain companies or countries, provided Janus Capital believes such use will assist the Fund in tracking the Underlying Index. Equity swaps involve the exchange by two parties of future cash flow (e.g., one cash flow based on a referenced interest rate and the other based on the performance of stock or a stock index).

Non-Index Investments

Although not considered a principal investment strategy, the Fund may invest in investments that are not included in the Underlying Index, but which Janus Capital believes will help the Fund track the Underlying Index. Such investments include common stocks, ADRs, GDRs, shares of other investment companies, and cash and cash equivalents, including money market funds. There may be instances where a stock is removed from the Underlying Index but Janus Capital may elect to hold it for tax-related purposes, or where the Fund receives non-Underlying Index stocks in a corporate action and does not sell the stocks until the next rebalance date. Janus Capital may also choose to hold non-Underlying Index stocks due to an optimization methodology to more efficiently track the Underlying Index. Use of an optimization methodology would entail the use of a program or model designed to identify securities that are not included in the Underlying Index, but would be expected to behave similarly to securities that are in the Underlying Index.

The value of your investment will vary over time, sometimes significantly, and you may lose money by investing in the Fund. The Fund invests substantially all of its assets in small-, mid- and large capitalization stocks. The following information is intended to help you better understand some of the risks of investing in the Fund. The impact of the following risks on the Fund may vary depending on the Fund’s investments. The greater the Fund’s investment in a particular security, the greater the Fund’s exposure to the risks associated with that security. Before investing in the Fund, you should consider carefully the risks that you assume when investing in the Fund.

Index Tracking Risk.  Tracking error refers to the risk that Janus Capital may not be able to cause the Fund’s performance to match or correlate to that of the Underlying Index, either on a daily or aggregate basis. There are a number of factors that may contribute to the Fund’s tracking error, such as Fund expenses, imperfect correlation between the Fund’s investments and those of the Underlying Index, settlement in foreign markets, rounding of share prices, the timing or magnitude of changes to the composition of the Underlying Index, regulatory policies, and a high portfolio turnover rate. The Fund incurs operating expenses not applicable to the Underlying Index and incurs costs associated with buying and selling securities, especially when rebalancing the Fund’s securities holdings to reflect changes in the composition of the Underlying Index. In addition, mathematical compounding may prevent the Fund from correlating with the monthly, quarterly, annual, or other period performance of the Underlying Index. Tracking error may cause the Fund’s performance to be less than expected.

Passive Investment Risk.  The Fund is not actively managed. Therefore, unless a specific security is removed from the Underlying Index, or the selling of shares of that security is otherwise required upon a rebalancing of the Underlying Index pursuant to the Underlying Index methodology, the Fund generally would not sell a security because the security’s issuer was in financial trouble. If a specific security is removed from the Underlying Index, the Fund may be forced to sell such security at an inopportune time or for a price other than the security’s current market value. An investment in the Fund involves risks similar to those of investing in equity securities traded on an exchange, such as market fluctuations caused by such factors as economic and political developments, changes in interest rates and perceived trends in security prices. It is anticipated that the value of Fund shares will decline, more or less, in correspondence with any decline in value of the Underlying Index.

The Underlying Index may not contain the appropriate mix of securities for any particular point in the business cycle of the overall economy, particular economic sectors, or narrow industries within which the commercial activities of the companies composing the portfolio securities holdings of the Fund are conducted, and the timing of movements from one type of security to another in seeking to replicate the Underlying Index could have a negative effect on the Fund. Unlike with an actively managed fund, Janus Capital does not use techniques or defensive strategies designed to lessen the effects of market volatility or to reduce the impact of periods of market decline. This means that, based on market and economic conditions, the Fund’s performance could be lower than other types of mutual funds that may actively shift their portfolio assets to take advantage of market opportunities or to lessen the impact of a market decline.

9_½Janus Detroit Street Trust

Fluctuation of NAV.  The NAV of the Fund shares will generally fluctuate with changes in the market value of the Fund’s securities holdings. The market prices of shares will generally fluctuate in accordance with changes in the Fund’s NAV and supply and demand of shares on the NASDAQ. It cannot be predicted whether Fund shares will trade below, at or above their NAV. Price differences may be due, in large part, to the fact that supply and demand forces at work in the secondary trading market for shares will be closely related to, but not identical to, the same forces influencing the prices of the securities of the Underlying Index trading individually or in the aggregate at any point in time. In addition, during periods of significant volatility, the liquidity of the underlying securities held by the Fund may affect the Fund’s trading prices. While the creation/redemption feature is designed to make it likely that Fund shares normally will trade close to the Fund’s NAV, disruptions to creations and redemptions may result in trading prices that differ significantly from the Fund’s NAV. An absence of trading in shares of the Fund, or a high volume of trading in the Fund, may result in trading prices that differ significantly from the Fund’s NAV. If an investor purchases Fund shares at a time when the market price is at a premium to the NAV of the shares or sells at a time when the market price is at a discount to the NAV of the shares, then the investor may sustain losses. Further, the securities held by the Fund may be traded in markets that close at a different time than the NASDAQ. Liquidity in those securities may be reduced after the applicable closing times. Accordingly, during the time when the NASDAQ is open but after the applicable market closing, bid-ask spreads and the resulting premium or discount to the Fund shares’ NAV may widen. Similarly, the NASDAQ may be closed at times or days when markets for securities held by the Fund are open, which may increase bid-ask spreads and the resulting premium or discount to the Fund shares’ NAV when the NASDAQ re-opens.

Transaction and Spread Risk.  Investors buying or selling Fund shares in the secondary market will pay brokerage commissions or other charges imposed by brokers as determined by that broker. Brokerage commissions are often a fixed amount and may be a significant proportional cost for investors seeking to buy or sell relatively small amounts of shares. In addition, secondary market investors will also incur the cost of the difference between the price that an investor is willing to pay for shares (the “bid” price) and the price at which an investor is willing to sell shares (the “ask” price). This difference in bid and ask prices is often referred to as the “spread” or “bid/ask spread.” The bid/ask spread varies over time for shares based on trading volume and market liquidity, and is generally lower if the Fund’s shares have more trading volume and market liquidity and higher if the Fund’s shares have little trading volume and market liquidity. Further, increased market volatility and trading halts affecting any of the Fund’s portfolio securities may cause increased bid/ask spreads. Due to the costs of buying or selling shares, including bid/ask spreads, frequent trading of shares may significantly reduce investment results and an investment in shares may not be advisable for investors who anticipate regularly making small investments.

Trading Issues Risk.  Trading in shares on the NASDAQ may be halted due to market conditions or for reasons that, in the view of the NASDAQ, make trading in shares inadvisable. In addition, trading in shares on the NASDAQ is subject to trading halts caused by extraordinary market volatility pursuant to the NASDAQ “circuit breaker” rules. There can be no assurance that the requirements of the NASDAQ necessary to maintain the listing of the Fund will continue to be met or will remain unchanged or that the shares will trade with any volume, or at all. While the creation/redemption feature is designed to make it likely that shares will trade close to the Fund’s NAV, disruptions to creations and redemptions may result in trading prices that differ significantly from the Fund’s NAV. If an investor purchases shares at a time when the market price is at a premium to the NAV of the shares or sells at a time when the market price is at a discount to the NAV of the shares, then the investor may sustain losses. In addition, during periods of significant volatility, the liquidity of the underlying securities held by the Fund may affect the Fund’s trading prices. For example, when the Fund’s underlying securities trade on foreign exchanges that are closed when the securities exchange on which the Fund’s shares trade is open, this may result in deviations between the current price of such an underlying security and the last quoted price for the underlying security. This could result in premiums or discounts to the Fund’s NAV. During a “flash crash,” the market prices of the Fund’s shares may decline suddenly and significantly. Such a decline may not reflect the performance of the portfolio securities held by the Fund. Flash crashes may cause Authorized Participants and other market makers to limit or cease trading in the Fund’s shares for temporary or longer periods. Shareholders could suffer significant losses to the extent that they sell shares at these temporarily low market prices.

ADR/GDR Risk.  To the extent the Fund seeks exposure to foreign companies, the Fund’s investments may be in the form of depositary receipts or other securities convertible into securities of foreign issuers, including ADRs and GDRs. While the use of ADRs and GDRs, which are traded on exchanges and represent ownership in foreign securities, provide an alternative to directly purchasing the underlying foreign securities in their respective national markets and currencies, investments in ADRs and GDRs continue to be subject to certain of the risks associated with investing directly in foreign securities.

10_½Janus Detroit Street Trust

Swap Risk.  Swap agreements entail the risk that a party will default on its payment obligations to the Fund. If the other party to a swap defaults, the Fund would risk the loss of the net amount of the payments that it contractually is entitled to receive. If the Fund utilizes a swap at the wrong time or judges market conditions incorrectly, the swap may result in a loss to the Fund.

Foreign Exposure Risk.  The Fund may invest in foreign equity securities either indirectly (e.g., depositary receipts, depositary shares, and passive foreign investment companies) or directly in foreign markets, including emerging markets. With respect to investments in securities of issuers or companies that are economically tied to different countries throughout the world, securities may be deemed to be economically tied to a particular country based on such factors as the issuer’s country of incorporation, primary listing, and other factors including, but not limited to operations, revenues, headquarters, management, and shareholder base. Investments in foreign securities, may involve greater risks than investing in domestic securities because the Fund’s performance may depend on factors other than the performance of a particular company. These factors include:

Eurozone Risk.  A number of countries in the European Union (“EU”) have experienced, and may continue to experience, severe economic and financial difficulties. In particular, many EU nations are susceptible to economic risks associated with high levels of debt, notably due to investments in sovereign debt. As a result, financial markets in the EU have been subject to increased

11_½Janus Detroit Street Trust

volatility and declines in asset values and liquidity. Responses to these financial problems by European governments, central banks, and others, including austerity measures and reforms, may not work, may result in social unrest, and may limit future growth and economic recovery or have other unintended consequences. Further defaults or restructurings by governments and others of their debt could have additional adverse effects on economies, financial markets, and asset valuations around the world. The risk of investing in securities in the European markets may also be heightened due to the referendum in which the United Kingdom voted to exit the EU (known as “Brexit”). One or more other countries may also abandon the euro and/or withdraw from the EU, placing its currency and banking system in jeopardy. The impact of these actions, especially if they occur in a disorderly fashion, is not clear but could be significant and far-reaching. To the extent that the Fund has exposure to European markets or to transactions tied to the value of the euro, these events could negatively affect the value and liquidity of the Fund’s investments. All of these developments may continue to significantly affect the economies of all EU countries, which in turn may have a material adverse effect on the Fund’s investments in such countries, other countries that depend on EU countries for significant amounts of trade or investment, or issuers with exposure to debt issued by certain EU countries.

These risks are described further in the SAI.

The Underlying Index is composed of stocks of companies selected by the Index Provider that are positioned to profit from servicing the obese. A company is deemed to service the obese by the Index Provider if its business is focused: (1) on obesity and obesity related disease including diabetes, high blood pressure, cholesterol, heart disease, stroke, and sleep apnea; or (2) on weight loss programs, weight loss supplements, or plus sized apparel. For a company to be deemed to service the obese, its obesity-related business as defined above must be a material driver of its current and future business. 100% of the companies in the Underlying Index will be obesity companies. For at least 80% of the Underlying Index, on a capitalization-weighted basis, a majority of a company’s revenues, sales, or assets comes from obesity business. The Index Provider may solicit public comment from time to time on companies that it should consider as eligible for inclusion in the Underlying Index.

For detailed information on how stocks are selected for inclusion in the Underlying Index, see the Solactive Obesity Index Methodology document, available at the Index Provider’s website.

The Underlying Index is compiled and administered by Solactive AG. The Index Provider is not affiliated with the Fund or Janus Capital.

12_½Janus Detroit Street Trust

The Fund pursues its investment objective by investing at least 80% of its net assets (plus any borrowings for investment purposes) in the stocks that comprise the Solactive Long Term Care Index (“Underlying Index”). The Underlying Index is designed to track the performance of companies globally that are positioned to profit from providing long-term care to the aging population, including companies owning or operating senior living facilities, nursing services, specialty hospitals, and senior housing, biotech companies for age-related illnesses, and companies that sell products and services to such facilities. Under normal circumstances, the Fund expects to invest substantially all of its assets in securities included in the Underlying Index, using a replication strategy as discussed below. The Fund may invest in companies of any capitalization, although at least 90% of the companies will have a capitalization of at least $100 million. The Fund may invest in real estate investment trusts (“REITs”) or similar vehicles or related securities that provide exposure to real estate. The Fund may invest in foreign issuers, including emerging markets. Stocks included in the Underlying Index may include common shares traded on local exchanges,

2_½The Long-Term Care ETF

American Depositary Receipts (“ADRs”) and Global Depositary Receipts (“GDRs”). ADRs and GDRs represent ownership interests in shares of foreign companies that are held in financial institution custodial accounts, and are traded on exchanges in the United States and around the world.

The Fund is classified as nondiversified, which allows it to hold larger positions in a smaller number of companies, compared to a fund that is classified as diversified.

The Underlying Index, the Solactive Long Term Care Index, was created by and is maintained by, Solactive AG (“Solactive” or the “Index Provider”). The Underlying Index is reconstituted on a semi-annual basis, rebalanced on a quarterly basis, and the Fund is rebalanced quarterly based on changes to the Underlying Index. The Fund uses a “passive,” index-based approach in seeking performance that corresponds to the performance of the Underlying Index. The underlying securities are weighted according to their market capitalization relative to other securities in the Underlying Index, and capped so that no security will represent more than 20% of the Underlying Index at the time of an index reconstitution or rebalance. Due to market movement between rebalancing and reconstitution of the Underlying Index, an underlying security may represent more than 20% of the Underlying Index at any given time, and thus may represent more than 20% of the Fund’s assets at any given time.

The Fund will generally use a replication methodology, meaning it will invest in the securities composing the Underlying Index in proportion to the weightings in the Underlying Index. However, the Fund may utilize a sampling methodology under various circumstances in which it may not be possible or practicable to purchase all of the securities in the Underlying Index. Janus Capital expects that over time, if the Fund has sufficient assets, the correlation between the Fund’s performance, before fees and expenses, and that of the Underlying Index will be 95% or better. A figure of 100% would indicate perfect correlation.

Under normal circumstances, the Fund expects to invest substantially all of its assets in securities included in the Underlying Index, although it may invest up to 20% its assets in other securities that Janus Capital believes will help the Fund track the Underlying Index. Such investments include stocks, shares of other investment companies, cash and cash equivalents, including money market funds.

To the extent the Underlying Index concentrates (i.e., holds 25% or more of its total assets) in the securities of a particular industry or group of industries, the Fund will concentrate its investments to approximately the same extent as the Underlying Index. As of February 1, 2020, approximately 64% of the Underlying Index was represented by companies in the Health Care REITs industry. For more recent information, see the Fund’s daily portfolio holdings posted on the ETF portion of the Janus Henderson website.

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.

The Fund’s Board of Trustees (“Trustees”) may change the Fund’s investment objective or non-fundamental principal investment strategies without a shareholder vote. The Fund will notify you in writing at least 60 days or as soon as reasonably practicable before making any such change it considers material. In addition, the Fund will provide shareholders with at least 60 days’ notice prior to changing the 80% investment policy. If there is a material change to the Fund’s objective or principal investment strategies, you should consider whether the Fund remains an appropriate investment for you. There is no guarantee that the Fund will achieve its investment objective.

The Fund’s portfolio holdings are disclosed on its website daily after the close of trading on the exchange and prior to the opening of trading on the exchange the following day. A description of the Fund’s policies and procedures with respect to the disclosure of the Fund’s portfolio holdings is available in the Fund’s SAI. Information about the premiums and discounts at which the Fund’s shares have traded is available at janushenderson.com/performance by selecting the Fund for additional details.

Unless otherwise stated, the following additional investment strategies and general policies apply to the Fund and provide further information including, but not limited to, the types of securities the Fund may invest in when implementing its investment objective. Some of these strategies and policies may be part of a principal strategy. Other strategies and policies may be utilized to a lesser extent. Except for the Fund’s policies with respect to investments in illiquid investments and borrowing, the percentage limitations included in these policies and elsewhere in this Prospectus and/or the SAI normally apply only at the time of initial purchase of a security. So, for example, if the Fund exceeds a limit as a result of market fluctuations or the sale of other securities, it will not be required to dispose of any securities and may continue to purchase such securities in order to track the Underlying Index.

Real Estate Investment Trusts

Real estate investment trusts (“REITs”) are often categorized as equity REITs, mortgage REITs, and hybrid REITs. An equity REIT, the most common type of REIT, invests primarily in the fee ownership of land and buildings. An equity REIT derives its income primarily from rental income but may also realize capital gains or losses by selling real estate properties in its portfolio that have appreciated or depreciated in value. A mortgage REIT invests primarily in mortgages on real estate, which may secure construction, development, or long-term loans. A mortgage REIT generally derives its income from interest payments on the credit it has extended. A hybrid REIT combines the characteristics of equity REITs and mortgage REITs, generally by holding both ownership interests and mortgage interests in real estate.

Securities Lending

Although not considered a principal investment strategy, the Fund may seek to earn additional income through lending its securities to certain qualified broker-dealers and institutions on a short-term or long-term basis. The Fund may lend portfolio

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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. When the Fund lends its securities, it receives collateral (including cash collateral), at least equal to the value of securities loaned. The Fund may earn income by investing this collateral in one or more affiliated or non-affiliated cash management vehicles. It is also possible that, due to a decline in the value of a cash management vehicle in which collateral is invested, the Fund may lose money. There is also 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 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. In certain circumstances, individual loan transactions could yield negative returns. To the extent Janus Capital manages the cash collateral in an affiliated cash management vehicle, it will receive an investment advisory fee for managing such assets.

Swaps

Although not considered a principal investment strategy, the Fund may utilize swap agreements including, but not limited to, equity swaps, as a means to gain exposure to certain companies or countries, provided Janus Capital believes such use will assist the Fund in tracking the Underlying Index. Equity swaps involve the exchange by two parties of future cash flow (e.g., one cash flow based on a referenced interest rate and the other based on the performance of stock or a stock index).

Non-Index Investments

Although not considered a principal investment strategy, the Fund may invest in investments that are not included in the Underlying Index, but which Janus Capital believes will help the Fund track the Underlying Index. Such investments include common stocks, ADRs, GDRs, shares of other investment companies, and cash and cash equivalents, including money market funds. There may be instances where a stock is removed from the Underlying Index but Janus Capital may elect to hold it for tax-related purposes, or where the Fund receives non-Underlying Index stocks in a corporate action and does not sell the stocks until the next rebalance date. Janus Capital may also choose to hold non-Underlying Index stocks due to an optimization methodology to more efficiently track the Underlying Index. Use of an optimization methodology would entail the use of a program or model designed to identify securities that are not included in the Underlying Index, but would be expected to behave similarly to securities that are in the Underlying Index.

The value of your investment will vary over time, sometimes significantly, and you may lose money by investing in the Fund. The Fund invests substantially all of its assets in small-, mid- and large capitalization stocks. The following information is intended to help you better understand some of the risks of investing in the Fund. The impact of the following risks on the Fund may vary depending on the Fund’s investments. The greater the Fund’s investment in a particular security, the greater the Fund’s exposure to the risks associated with that security. Before investing in the Fund, you should consider carefully the risks that you assume when investing in the Fund.

Real Estate Securities Risk.  To the extent it holds equity and/or debt securities of real estate-related companies, the Fund may be affected by the risks associated with real estate investments. The value of securities of companies in real estate and real estate-related industries, including securities of REITs, is sensitive to decreases in real estate values and rental income, property taxes, interest rates, tax and regulatory requirements, overbuilding/supply and demand, increased competition, local and general economic conditions, increases in operating costs, environmental liabilities, management skill in running a REIT, and the creditworthiness of the REIT. If the Fund has REIT investments, the Fund’s shareholders will indirectly bear their proportionate share of the REIT’s expenses, in addition to their proportionate share of the Fund’s expenses.

REIT Risk.  To the extent that the Fund holds REITs, it may be subject to the additional risks associated with REIT investments. The ability to trade REITs in the secondary market can be more limited compared to other equity investments, and certain REITs have relatively small market capitalizations, which can increase the volatility of the market price for their securities. REITs are also subject to heavy cash flow dependency to allow them to make distributions to their shareholders. The prices of equity REITs are affected by changes in the value of the underlying property owned by the REITs and changes in capital markets and interest rates. Equity REITs generally are not diversified and are subject to heavy cash flow dependency, defaults by borrowers, and self-liquidation. There is also the risk that borrowers under mortgages held by a REIT or lessees of a property that a REIT owns may be unable to meet their obligations to the REIT. In the event of a default by a borrower or lessee, the REIT may incur substantial costs associated with protecting its investments.

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Index Tracking Risk.  Tracking error refers to the risk that Janus Capital may not be able to cause the Fund’s performance to match or correlate to that of the Underlying Index, either on a daily or aggregate basis. There are a number of factors that may contribute to the Fund’s tracking error, such as Fund expenses, imperfect correlation between the Fund’s investments and those of the Underlying Index, rounding of share prices, the timing or magnitude of changes to the composition of the Underlying Index, settlement in foreign markets, regulatory policies, and a high portfolio turnover rate. The Fund incurs operating expenses not applicable to the Underlying Index and incurs costs associated with buying and selling securities, especially when rebalancing the Fund’s securities holdings to reflect changes in the composition of the Underlying Index. In addition, mathematical compounding may prevent the Fund from correlating with the monthly, quarterly, annual, or other period performance of the Underlying Index. Tracking error may cause the Fund’s performance to be less than expected.

Passive Investment Risk.  The Fund is not actively managed. Therefore, unless a specific security is removed from the Underlying Index, or the selling of shares of that security is otherwise required upon a rebalancing of the Underlying Index pursuant to the Underlying Index methodology, the Fund generally would not sell a security because the security’s issuer was in financial trouble. If a specific security is removed from the Underlying Index, the Fund may be forced to sell such security at an inopportune time or for a price other than the security’s current market value. An investment in the Fund involves risks similar to those of investing in equity securities traded on an exchange, such as market fluctuations caused by such factors as economic and political developments, changes in interest rates and perceived trends in security prices. It is anticipated that the value of Fund shares will decline, more or less, in correspondence with any decline in value of the Underlying Index.

The Underlying Index may not contain the appropriate mix of securities for any particular point in the business cycle of the overall economy, particular economic sectors, or narrow industries within which the commercial activities of the companies composing the portfolio securities holdings of the Fund are conducted, and the timing of movements from one type of security to another in seeking to replicate the Underlying Index could have a negative effect on the Fund. Unlike with an actively managed fund, Janus Capital does not use techniques or defensive strategies designed to lessen the effects of market volatility or to reduce the impact of periods of market decline. This means that, based on market and economic conditions, the Fund’s performance could be lower than other types of mutual funds that may actively shift their portfolio assets to take advantage of market opportunities or to lessen the impact of a market decline.

Fluctuation of NAV.  The NAV of the Fund’s shares will generally fluctuate with changes in the market value of the Fund’s securities holdings. The market prices of shares will generally fluctuate in accordance with changes in the Fund’s NAV and supply and demand of shares on the NASDAQ. It cannot be predicted whether Fund shares will trade below, at or above their NAV. Price differences may be due, in large part, to the fact that supply and demand forces at work in the secondary trading market for shares will be closely related to, but not identical to, the same forces influencing the prices of the securities of the Underlying Index trading individually or in the aggregate at any point in time. In addition, during periods of significant volatility, the liquidity of the underlying securities held by the Fund may affect the Fund’s trading prices. While the creation/redemption feature is designed to make it likely that Fund shares normally will trade close to the Fund’s NAV, disruptions to creations and redemptions may result in trading prices that differ significantly from the Fund’s NAV. An absence of trading in shares of the Fund, or a high volume of trading in the Fund, may result in trading prices that differ significantly from the Fund’s NAV. If an investor purchases Fund shares at a time when the market price is at a premium to the NAV of the shares or sells at a time when the market price is at a discount to the NAV of the shares, then the investor may sustain losses. Further, the securities held by the Fund may be traded in markets that close at a different time than the NASDAQ. Liquidity in those securities may be reduced after the applicable closing times. Accordingly, during the time when the NASDAQ is open but after the applicable market closing, bid-ask spreads and the resulting premium or discount to the Fund shares’ NAV may widen. Similarly, the NASDAQ may be closed at times or days when markets for securities held by the Fund are open, which may increase bid-ask spreads and the resulting premium or discount to the Fund shares’ NAV when the NASDAQ re-opens.

Transaction and Spread Risk.  Investors buying or selling Fund shares in the secondary market will pay brokerage commissions or other charges imposed by brokers as determined by that broker. Brokerage commissions are often a fixed amount and may be a significant proportional cost for investors seeking to buy or sell relatively small amounts of shares. In addition, secondary market investors will also incur the cost of the difference between the price that an investor is willing to pay for shares (the “bid” price) and the price at which an investor is willing to sell shares (the “ask” price). This difference in bid and ask prices is often referred to as the “spread” or “bid/ask spread.” The bid/ask spread varies over time for shares based on trading volume and market liquidity, and is generally lower if the Fund’s shares have more trading volume and market liquidity and higher if the Fund’s shares have little trading volume and market liquidity. Further, increased market volatility and trading halts affecting any of the Fund’s portfolio securities may cause increased bid/ask spreads. Due to the costs of buying or selling shares, including

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bid/ask spreads, frequent trading of shares may significantly reduce investment results and an investment in shares may not be advisable for investors who anticipate regularly making small investments.

Trading Issues Risk.  Trading in shares on the NASDAQ may be halted due to market conditions or for reasons that, in the view of the NASDAQ, make trading in shares inadvisable. In addition, trading in shares on the NASDAQ is subject to trading halts caused by extraordinary market volatility pursuant to the NASDAQ “circuit breaker” rules. There can be no assurance that the requirements of the NASDAQ necessary to maintain the listing of the Fund will continue to be met or will remain unchanged or that the shares will trade with any volume, or at all. While the creation/redemption feature is designed to make it likely that shares will trade close to the Fund’s NAV, disruptions to creations and redemptions may result in trading prices that differ significantly from the Fund’s NAV. If an investor purchases shares at a time when the market price is at a premium to the NAV of the shares or sells at a time when the market price is at a discount to the NAV of the shares, then the investor may sustain losses. In addition, during periods of significant volatility, the liquidity of the underlying securities held by the Fund may affect the Fund’s trading prices. For example, when the Fund’s underlying securities trade on foreign exchanges that are closed when the securities exchange on which the Fund’s shares trade is open, this may result in deviations between the current price of such an underlying security and the last quoted price for the underlying security. This could result in premiums or discounts to the Fund’s NAV. During a “flash crash,” the market prices of the Fund’s shares may decline suddenly and significantly. Such a decline may not reflect the performance of the portfolio securities held by the Fund. Flash crashes may cause Authorized Participants and other market makers to limit or cease trading in the Fund’s shares for temporary or longer periods. Shareholders could suffer significant losses to the extent that they sell shares at these temporarily low market prices.

ADR/GDR Risk.  To the extent the Fund seeks exposure to foreign companies, the Fund’s investments may be in the form of depositary receipts or other securities convertible into securities of foreign issuers, including ADRs and GDRs. While the use of ADRs and GDRs, which are traded on exchanges and represent ownership in foreign securities, provide an alternative to directly purchasing the underlying foreign securities in their respective national markets and currencies, investments in ADRs and GDRs continue to be subject to certain of the risks associated with investing directly in foreign securities.

Swap Risk.  Swap agreements entail the risk that a party will default on its payment obligations to the Fund. If the other party to a swap defaults, the Fund would risk the loss of the net amount of the payments that it contractually is entitled to receive. If the Fund utilizes a swap at the wrong time or judges market conditions incorrectly, the swap may result in a loss to the Fund.

Foreign Exposure Risk.  The Fund may invest in foreign equity securities either indirectly (e.g., depositary receipts, depositary shares, and passive foreign investment companies) or directly in foreign markets, including emerging markets. With respect to investments in securities of issuers or companies that are economically tied to different countries throughout the world, securities may be deemed to be economically tied to a particular country based on such factors as the issuer’s country of incorporation, primary listing, and other factors including, but not limited to operations, revenues, headquarters, management, and shareholder base. Investments in foreign securities, may involve greater risks than investing in domestic securities because the Fund’s performance may depend on factors other than the performance of a particular company. These factors include:

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Eurozone Risk.  A number of countries in the European Union (“EU”) have experienced, and may continue to experience, severe economic and financial difficulties. In particular, many EU nations are susceptible to economic risks associated with high levels of debt, notably due to investments in sovereign debt. As a result, financial markets in the EU have been subject to increased volatility and declines in asset values and liquidity. Responses to these financial problems by European governments, central banks, and others, including austerity measures and reforms, may not work, may result in social unrest, and may limit future growth and economic recovery or have other unintended consequences. Further defaults or restructurings by governments and others of their debt could have additional adverse effects on economies, financial markets, and asset valuations around the world. The risk of investing in securities in the European markets may also be heightened due to the referendum in which the United Kingdom voted to exit the EU (known as “Brexit”). One or more other countries may also abandon the euro and/or withdraw from the EU, placing its currency and banking system in jeopardy. The impact of these actions, especially if they occur in a disorderly fashion, is not clear but could be significant and far-reaching. To the extent that the Fund has exposure to European markets or to transactions tied to the value of the euro, these events could negatively affect the value and liquidity of the Fund’s investments. All of these developments may continue to significantly affect the economies of all EU countries, which in turn may have a material adverse effect on the Fund’s investments in such countries, other countries that depend on EU countries for significant amounts of trade or investment, or issuers with exposure to debt issued by certain EU countries.

These risks are described further in the SAI.

The Underlying Index is composed of stocks of companies selected by the Index Provider that are positioned to profit from providing long-term care to the aging population. A company is deemed to be a long-term care company by the Index Provider if it (1) owns or operates senior living facilities, senior housing, nursing services, or specialty hospitals primarily serving the elderly, or (2) sells products and services to such facilities. For a company to be deemed a long-term care company, its long-term care related business as defined above must be a material driver of its current and future business. 100% of the companies in the Underlying Index will be long-term care companies. For at least 80% of the Underlying Index, on a capitalization-weighted basis, a majority of a company’s revenues, sales, or assets comes from long-term care business. The Index Provider may solicit public comment from time to time on companies that it should consider as eligible for inclusion in the Underlying Index.

For detailed information on how stocks are selected for inclusion in the Underlying Index, see the Solactive Long Term Care Index Methodology document, available at the Index Provider’s website.

The Underlying Index is compiled and administered by Solactive AG. The Index Provider is not affiliated with the Fund or Janus Capital.

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