Summary Prospectus by Investment Company - Form 497K

Summary Prospectus-October 31, 2024

Before you invest in the SPDR® Portfolio S&P 400 Mid Cap ETF (the "Fund"), you may want to review the Fund's prospectus and statement of additional information, which contain more information about the Fund and the risks of investing in the Fund. The Fund's prospectus and statement of additional information dated October 31, 2024, are incorporated by reference into this summary prospectus. You can find the Fund's prospectus, statement of additional information and reports to shareholders, as well as other information about the Fund, online at https://www.ssga.com.

You may also obtain this information at no charge by calling 1-866-787-2257 or by sending an e-mail request to [email protected].

Investment Objective

The SPDR Portfolio S&P 400 Mid Cap ETF (the "Fund") seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of an index that tracks the performance of mid- capitalization exchange traded U.S. equity securities.

Fees and Expenses of the Fund

The table below describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund ("Fund Shares"). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and Example below.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):

Management fees	0.03%
Distribution and service (12b-1) fees	None
Other expenses	0.00%
Total annual Fund operating expenses	0.03%

Example:

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

Year 1	Year 3	Year 5	Year 10
$3	$10	$17	$39

Portfolio Turnover:

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 20% of the average value of its portfolio.

The Fund's Principal Investment Strategy

In seeking to track the performance of the S&P MidCap 400 Index(the "Index"), the Fund employs a sampling strategy, which means that the Fund is not required to purchase all of the securities represented in the Index. Instead, the Fund may purchase a subset of the securities in the Index in an effort to hold a portfolio of securities with generally the same risk and return characteristics of the Index. The quantity of holdings in the Fund will be based on a number of factors, including asset size of the Fund. Based on its analysis of these factors, SSGA Funds Management, Inc. ("SSGA FM" or the "Adviser"), the investment adviser

to the Fund, either may invest the Fund's assets in a subset of securities in the Index or may invest the Fund's assets in substantially all of the securities represented in the Index in approximately the same proportions as the Index, as determined by the Adviser to be in the best interest of the Fund in pursuing its objective.

Under normal market conditions, the Fund generally invests substantially all, but at least 80%, of its total assets in the securities comprising the Index. In addition, in seeking to track the Index, the Fund may invest in equity securities that are not included in the Index. The Fund may also invest in cash and cash equivalents or money market instruments (including money market funds advised by the Adviser) for cash management purposes. In seeking to track the Index, the Fund's assets may be concentrated in an industry or group of industries, but only to the extent that the Index concentrates in a particular industry or group of industries. Futures contracts (a type of derivative instrument) may be used by the Fund in seeking performance that corresponds to the Index and in managing cash flows.

The Index is designed to measure the performance of the mid-capitalization segment of the U.S. equity market. The selection universe for the Index includes all U.S. common equities listed on the NYSE, NYSE Arca, NYSE American, NASDAQ Global Select Market, NASDAQ Global Market, NASDAQ Capital Market, Cboe BZX, Cboe BYX, Cboe EDGA, or Cboe EDGX with unadjusted market capitalizations between $6.7 billion and $18 billion and float-adjusted market capitalizations of at least $3.35 billion at the time of inclusion. These capitalization ranges may be revised by the Index Provider (as defined below) at any time. To be included in the Index, a security (or issuer of a security, as applicable) should (i) have an annual dollar value traded to float-adjusted market capitalization ratio of 0.75 or greater at the time of addition to the S&P Composite 1500 Index (the Index's parent index); (ii) trade a minimum of 250,000 shares in each of the six months leading up to the evaluation date; (iii) have a public float of at least 10%; and (iv) have positive aggregate earnings over the four most recent quarters and for the most recent quarter. In selecting securities for inclusion in the Index, the Index Provider also considers sector balance by comparing the weight of each GICS (Global Industry Classification Standard) sector in the Index to its weight in the relevant market capitalization range of the S&P Total Market Index.

The Index is float-adjusted market capitalization weighted. Index constituents are added and removed on an as-needed basis. The Index is rebalanced on a quarterly basis in March, June, September and December. As of August 31, 2024, a significant portion of the Fund comprised companies in the industrial and financial sectors, although this may change from time to time. As of July 31, 2024, the Index comprised 401 stocks.

The Index is sponsored by S&P Dow Jones Indices LLC (the "Index Provider"), which is not affiliated with the Fund or the Adviser. The Index Provider determines the composition of the Index, relative weightings of the securities in the Index and publishes information regarding the market value of the Index.

Principal Risks of Investing in the Fund

As with all investments, there are certain risks of investing in the Fund. Fund Shares will change in value, and you could lose money by investing in the Fund. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

Market Risk: The Fund's investments are subject to changes in general economic conditions, general market fluctuations and the risks inherent in investment in securities markets. Investment markets can be volatile and prices of investments can change substantially due to various factors including, but not limited to, economic growth or recession, changes in interest rates, inflation, changes in the actual or perceived creditworthiness of issuers, and general market liquidity. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. Local, regional or global events such as war, military conflicts, acts of terrorism, natural disasters, the spread of infectious illness or other public health issues, or other events could have a significant impact on the Fund and its investments.

Equity Investing Risk: The market prices of equity securities owned by the Fund may go up or down, sometimes rapidly or unpredictably. The value of a security may decline for a number of reasons that may directly relate to the issuer and also may decline due to general industry or market conditions that are not specifically related to a particular company. In addition, equity markets tend to move in cycles, which may cause stock prices to fall over short or extended periods of time.

Mid-Capitalization Securities Risk: The securities of mid-capitalization companies may be more volatile and may involve more risk than the securities of larger companies. These companies may have limited product lines, markets or financial resources, may lack the competitive strength of larger companies, and may depend on a few key employees. In addition, these companies may have been recently organized and may have little or no track record of success. The securities of mid-sized companies may trade less frequently and in smaller volumes than more widely held securities. Some securities of mid-sized issuers may be illiquid or may be restricted as to resale, and their values may be volatile.

Fluctuation of Net Asset Value, Share Premiums and Discounts Risk: As with all exchange-traded funds, Fund Shares may be bought and sold in the secondary market at market prices. The trading prices of Fund Shares in the secondary market may differ from the Fund's daily net asset value per share and there may be times when the market price of the shares is more than the net asset value per share (premium) or less than the net asset value per share (discount). This risk is heightened in times of market volatility or periods of steep market declines.

Financial Sector Risk: Financial services companies are subject to extensive governmental regulation, which may limit both the amounts and types of loans and other financial commitments they can make, the interest rates and fees they can charge, the scope of their activities, the prices they can charge and the amount of capital they must maintain. Profitability is largely dependent on the availability and cost of capital funds and can fluctuate significantly when interest rates change or due to increased competition. In addition, deterioration of the credit markets generally may cause an adverse impact in a broad range of markets, including U.S. and international credit and interbank money markets generally, thereby affecting a wide range of financial institutions and markets. Certain events in the financial sector may cause an unusually high degree of volatility in the financial markets, both domestic and foreign, and cause certain financial services companies to incur large losses. Securities of financial services companies may experience a dramatic decline in value when such companies experience substantial declines in the valuations of their assets, take action to raise capital (such as the issuance of debt or equity securities), or cease operations. Credit losses resulting from financial difficulties of borrowers and financial losses associated with investment activities can negatively impact the sector. Insurance companies may be subject to severe price competition. Adverse economic, business or political developments could adversely affect financial institutions engaged in mortgage finance or other lending or investing activities directly or indirectly connected to the value of real estate.

Futures Contract Risk: A futures contract is a standardized agreement that calls for the purchase or sale of a specific asset at a specific price at a specific future time, or cash settlement of the terms of the contract. Transactions in futures contracts can create investment leverage and may have significant volatility. It is possible that a futures contract transaction will result in a much greater loss than the principal amount invested, and the Fund may not be able to close out the futures contract at a favorable time or price. There is no assurance that a liquid secondary market on an exchange will exist for any particular futures contract. In the event no such market exists, it might not be possible to effect closing transactions, and the Fund will be unable to terminate its exposure to the futures contract. There is also a risk of imperfect correlation between movements in the prices of the futures contract and movements in the price of the underlying assets. The counterparty to a futures contract may be unable or unwilling to make timely settlement payments, return the Fund's margin, or otherwise honor its obligations.

Indexing Strategy/Index Tracking Risk: The Fund is managed with an indexing investment strategy, attempting to track the performance of an unmanaged index of securities, regardless of the current or projected performance of the Index or of the actual securities comprising the Index. This differs from an actively-managed fund, which typically seeks to outperform a benchmark index. As a result, the Fund's performance may be less favorable than that of a portfolio managed using an active investment strategy. The structure and composition of the Index will affect the performance, volatility, and risk of the Index and, consequently, the performance, volatility, and risk of the Fund. Errors in index data, index computations or the construction of the Index in accordance with its methodology may occur from time to time and may not be identified and corrected by the Index Provider for a period of time or at all, which may have an adverse impact on the Fund and its shareholders. To the extent circumstances evolve in between reconstitutions, the Index may include, and the Fund may therefore hold for a period of time, securities of companies that do not align with the Index's objective and/or criteria. When there are changes made to the component securities of the Index and the Fund in turn makes similar changes to its portfolio, any transaction costs and market exposure arising from such portfolio changes will be borne directly by the Fund and its shareholders. The Fund may recognize gains as a result of rebalancing or reconstituting its securities holdings to reflect changes in the securities included in the Index. The Fund also may be required to distribute any such gains to its shareholders to avoid adverse federal income tax consequences. While the Adviser seeks to track the performance of the Index (i.e., achieve a high degree of correlation with the Index), the Fund's return may not match the return of the Index. The Fund incurs a number of operating expenses not applicable to the Index, and incurs costs in buying and selling securities. In addition, the Fund may not be fully invested at times, generally as a result of cash flows into or out of the Fund or reserves of cash held by the Fund to meet redemptions. The Adviser may attempt to track the Index return by investing in fewer than all of the securities in the Index, or in some securities not included in the Index, potentially increasing the risk of divergence between the Fund's return and that of the Index.

Industrial Sector Risk: Industrial companies are affected by supply and demand both for their specific product or service and for industrial sector products and services in general. Government regulation, world events, exchange rates and economic conditions, technological developments and liabilities for environmental damage and general civil liabilities will likewise affect the performance of these companies. Aerospace and defense companies, a component of the industrial sector, can be significantly affected by government spending policies because companies involved in this industry rely, to a significant extent, on U.S. and foreign government demand for their products and services. Thus, the financial condition of, and investor interest in, aerospace and defense companies are heavily influenced by governmental defense spending policies which are typically under pressure from

efforts to control the U.S. (and other) government budgets. Transportation securities, another component of the industrial sector, are cyclical and have occasional sharp price movements which may result from changes in the economy, fuel prices, labor agreements and insurance costs.

Unconstrained Sector Risk: The Fund may invest a substantial portion of its assets within one or more economic sectors or industries, which may change from time to time. Greater investment focus on one or more sectors or industries increases the potential for volatility and the risk that events negatively affecting such sectors or industries could reduce returns, potentially causing the value of the Fund's Shares to decrease, perhaps significantly.

Valuation Risk: Certain portfolio holdings may be valued on the basis of factors other than market quotations. This may occur more often in times of market turmoil or reduced liquidity. There are multiple methods that can be used to value a portfolio holding when market quotations are not readily available. The value established for any portfolio holding at a point in time might differ from what would be produced using a different methodology or if it had been priced using market quotations. Portfolio holdings that are valued using techniques other than market quotations, including "fair valued" securities, may be subject to greater fluctuation in their valuations from one day to the next than if market quotations were used. In addition, there is no assurance that the Fund could sell or close out a portfolio position for the value established for it at any time, and it is possible that the Fund would incur a loss because a portfolio position is sold or closed out at a discount to the valuation established by the Fund at that time.

Fund Performance

The following bar chart and table provide an indication of the risks of investing in the Fund by showing changes in the Fund's performance from year to year and by showing how the Fund's average annual returns for certain time periods compare with the average annual returns of the Index and of a relevant broad-based securities index. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. Updated performance information is available by calling 1-866-787-2257 or visiting our website at https://www.ssga.com.

Annual Total Returns (years ended 12/31)

	Returns	Quarter/Year
Highest Quarterly Return	24.31%	Q4 2020
Lowest Quarterly Return	-29.75%	Q1 2020
Year-to-Date	13.47%	9/30/2024

Average Annual Total Returns (for periods ended 12/31/23)

The after-tax returns presented in the table below are calculated using highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Your actual after-tax returns will depend on your specific tax situation and may differ from those shown below. After-tax returns are not relevant to investors who hold Fund Shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. The returns after taxes can exceed the returns before taxes due to an assumed tax benefit for a shareholder from realizing a capital loss on a sale of Fund Shares. Effective July 9, 2013, the Fund's benchmark index changed from the Dow Jones U.S. Mid-Cap Total Stock Market Index to the Russell Small Cap Completeness Index. Effective August 31, 2016, the Fund's benchmark index changed from the Russell Small Cap Completeness Index to the S&P 1000 Index. Effective January 24, 2020, the Fund's benchmark index changed from the S&P 1000 Index to the S&P MidCap 400 Index. Each benchmark index change was consistent with a change in the Fund's principal investment strategy to track the performance of a new index. Performance of the Fund prior to January 24, 2020 is therefore based on the Fund's investment strategy to track the applicable prior indexes and may have been different had the Fund tracked the current index.

	One Year	Five Years	Ten Years
Return Before Taxes	16.42 %	12.36 %	8.53 %
Return After Taxes on Distributions	15.89 %	11.87 %	7.73 %
Return After Taxes on Distributions and Sale of Fund Shares	9.90 %	9.74 %	6.60 %
S&P MidCap 400 Index/S&P 1000 Index/Russell Small Cap Completeness Index/Dow Jones U.S. Mid-Cap Total Stock Market Index1 (reflects no deduction for fees, expenses or taxes)	16.44 %	12.42 %	8.58 %
S&P 500 Index (reflects no deduction for fees, expenses or taxes)	26.29 %	15.69 %	12.03 %

Portfolio Management

Investment Adviser

SSGA FM serves as the investment adviser to the Fund.

Portfolio Managers

The professionals primarily responsible for the day-to-day management of the Fund are Karl Schneider and Mark Krivitsky.

Karl Schneider, CAIA, is a Managing Director of the Adviser and Co-Head of the Systematic Equity Beta Group in the Americas. He joined the Adviser in 1997.

Mark Krivitsky is a Vice President of the Adviser and a Senior Portfolio Manager in the Systematic Equity Beta Group and the Tax-Efficient Market Capture Group. He joined the Adviser in 1996.

Purchase and Sale Information

The Fund will issue (or redeem) Fund Shares to certain institutional investors (typically market makers or other broker-dealers) only in large blocks of Fund Shares known as "Creation Units." Creation Unit transactions are conducted in exchange for the deposit or delivery of a designated portfolio of in-kind securities and/or cash.

Individual Fund Shares may only be purchased and sold on the NYSE Arca, Inc., other national securities exchanges, electronic crossing networks and other alternative trading systems through your broker-dealer at market prices. Because Fund Shares trade at market prices rather than at net asset value ("NAV"), Fund Shares may trade at a price greater than NAV (premium) or less than NAV (discount). When buying or selling Fund Shares in the secondary market, you may incur costs attributable to the difference between the highest price a buyer is willing to pay to purchase Fund Shares (bid) and the lowest price a seller is willing to accept for Fund Shares (ask) (the "bid-ask spread"). Recent information regarding the Fund's NAV, market price, premiums and discounts, and bid-ask spreads is available at https://www.ssga.com.

Tax Information

The Fund's distributions are expected to be taxed as ordinary income, qualified dividend income and/or capital gains, unless you are investing through a tax-advantaged arrangement, such as a 401(k) plan or individual retirement account. Any withdrawals made from such tax-advantaged arrangement may be taxable to you.

Payments to Broker-Dealers and Other Financial Intermediaries

If you purchase Fund Shares through a broker-dealer or other financial intermediary (such as a bank), the Adviser or its affiliates may pay the financial intermediary for certain activities related to the Fund, including educational training programs, conferences, the development of technology platforms and reporting systems, or other services related to the sale or promotion of the Fund. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your financial intermediary's website for more information.

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