[424B2] MORGAN STANLEY Prospectus Supplement

Rhea-AI Filing Summary

Morgan Stanley Finance LLC is offering Dual Directional Trigger PLUS linked to the S&P 500 Futures Excess Return Index, maturing on November 5, 2031. These principal-at-risk notes pay no interest and are fully and unconditionally guaranteed by Morgan Stanley.

At maturity, if the final index level is above the initial level, holders receive $1,000 plus a leveraged upside equal to 164% of the index gain. If the index is at or below the initial level but at or above the downside threshold, investors receive $1,000 plus a positive return equal to the absolute index decline at a 100% participation rate, effectively capped at a 40% gain. If the final level is below the downside threshold (set at 60% of the initial level), principal is reduced 1% for every 1% index decline, and the payout could be zero.

The issue price is $1,000 per note, the estimated value on the pricing date is approximately $935.20 per note (within $55.00 of that estimate), agent’s sales commission is $32.50 per note, and proceeds to the issuer are $967.50 per note. The observation date is October 31, 2031. The notes will not be listed and are subject to Morgan Stanley/MSFL credit risk.

Insights

Structured products analyst

Leveraged, principal-at-risk note with dual-direction payoff and a 60% threshold.

The note offers 164% upside participation when the SPXFP index finishes above the initial level, and a dual-direction feature that pays the absolute decline at a 100% rate if the final level stays at or above 60% of the initial. The absolute-return side is effectively capped at a 40% gain, limiting benefits from moderate declines.

Below the threshold, losses are linear with the index decline, down to zero. Credit exposure is to Morgan Stanley Finance LLC, guaranteed by Morgan Stanley. Pricing includes selling and structuring costs; the estimated value is approximately $935.20 per note versus a $1,000 issue price.

Key dates are the observation on October 31, 2031 and maturity on November 5, 2031. Secondary liquidity is not assured; market making is discretionary.

Preliminary Pricing Supplement No. 11,391

Registration Statement Nos. 333-275587; 333-275587-01

Dated October 15, 2025

Filed pursuant to Rule 424(b)(2)

Morgan Stanley Finance LLC

Structured Investments

Dual Directional Trigger PLUS due November 5, 2031

Based on the Performance of the S&P 500® Futures Excess Return Index‬

Trigger Performance Leveraged Upside SecuritiesSM

Fully and Unconditionally Guaranteed by Morgan Stanley

Principal at Risk Securities

￭The Dual Directional Trigger PLUS (the “securities”) are unsecured obligations of Morgan Stanley Finance LLC (“MSFL”) and are fully and unconditionally guaranteed by Morgan Stanley. The securities will pay no interest, do not guarantee any return of principal at maturity and have the terms described in the accompanying product supplement, index supplement and prospectus, as supplemented or modified by this document.

￭Payment at maturity. At maturity, if the final level is greater than the initial level, investors will receive the stated principal amount plus the leveraged upside payment. If the final level is equal to or less than the initial level but is greater than or equal to the downside threshold level, investors will receive at maturity the stated principal amount plus a positive return equal to (i) the absolute value of the percentage decline in the level of the underlier multiplied by (ii) the absolute return participation rate. If, however, the final level is less than the downside threshold level, investors will lose 1% for every 1% decline in the level of the underlier over the term of the securities. Under these circumstances, the payment at maturity will be significantly less than the stated principal amount and could be zero.

￭The securities are for investors who seek a return based on the performance of the underlier and who are willing to risk their principal and forgo current income in exchange for the upside leverage feature as well as the absolute return participation feature and the limited protection against loss of principal, each of which applies only to a certain range of negative performance of the underlier over the term of the securities. Investors in the securities must be willing to accept the risk of losing their entire initial investment. The securities are notes issued as part of MSFL’s Series A Global Medium-Term Notes program.

￭All payments are subject to our credit risk. If we default on our obligations, you could lose some or all of your investment. These securities are not secured obligations and you will not have any security interest in, or otherwise have any access to, any underlying reference asset or assets.

TERMS
Issuer:	Morgan Stanley Finance LLC
Guarantor:	Morgan Stanley
Stated principal amount:	$1,000 per security
Issue price:	$1,000 per security (see “Commissions and issue price” below)
Aggregate principal amount:	$
Underlier:	S&P 500® Futures Excess Return Index‬ (the “underlying index”)
Strike date:	October 31, 2025
Pricing date:	October 31, 2025
Original issue date:	November 5, 2025
Observation date:	October 31, 2031, subject to postponement for non-trading days and certain market disruption events
Maturity date:	November 5, 2031
	Terms continued on the following page
Agent:	Morgan Stanley & Co. LLC (“MS & Co.”), an affiliate of MSFL and a wholly owned subsidiary of Morgan Stanley. See “Supplemental information regarding plan of distribution; conflicts of interest.”
Estimated value on the pricing date:	Approximately $935.20 per security, or within $55.00 of that estimate. See “Estimated Value of the Securities” on page 3.
Commissions and issue price:	Price to public	Agent’s commissions and fees(1)	Proceeds to us(2)
Per security	$1,000	$32.50	$967.50
Total	$	$	$

(1)Selected dealers and their financial advisors will collectively receive from the agent, MS & Co., a fixed sales commission of $32.50 for each security they sell. In addition, selected dealers and their financial advisors will receive a structuring fee of up to $9 for each security from the agent or its affiliates. See “Supplemental information regarding plan of distribution; conflicts of interest.” For additional information, see “Plan of Distribution (Conflicts of Interest)” in the accompanying product supplement.

(2)See “Use of Proceeds and Hedging” in the accompanying product supplement.

The securities involve risks not associated with an investment in ordinary debt securities. See “Risk Factors” beginning on page 5.

The Securities and Exchange Commission and state securities regulators have not approved or disapproved these securities, or determined if this document or the accompanying product supplement, index supplement and prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The securities are not deposits or savings accounts and are not insured by the Federal Deposit Insurance Corporation or any other governmental agency or instrumentality, nor are they obligations of, or guaranteed by, a bank.

You should read this document together with the related product supplement, index supplement and prospectus, each of which can be accessed via the hyperlinks below. When you read the accompanying index supplement, please note that all references in such supplement to the prospectus dated November 16, 2023, or to any sections therein, should refer instead to the accompanying prospectus dated April 12, 2024 or to the corresponding sections of such prospectus, as applicable. Please also see “Additional Terms of the Securities” and “Additional Information About the Securities” at the end of this document.

References to “we,” “us” and “our” refer to Morgan Stanley or MSFL, or Morgan Stanley and MSFL collectively, as the context requires.

Product Supplement for Principal at Risk Securities dated February 7, 2025 Index Supplement dated November 16, 2023 Prospectus dated April 12, 2024

Morgan Stanley Finance LLC

Dual Directional Trigger PLUS

Principal at Risk Securities

Terms continued from the previous page
Payment at maturity per security:	•If the final level is greater than the initial level: stated principal amount + leveraged upside payment •If the final level is equal to or less than the initial level but is greater than or equal to the downside threshold level: stated principal amount + (stated principal amount × absolute underlier return × absolute return participation rate) Under these circumstances, the payment at maturity will effectively be limited to a positive return of 40%. •If the final level is less than the downside threshold level: stated principal amount × performance factor Under these circumstances, the payment at maturity will be significantly less than the stated principal amount and could be zero.
Final level:	The closing level of the underlier on the observation date
Initial level:	, which is the closing level of the underlier on the strike date
Leveraged upside payment:	stated principal amount × leverage factor × underlier percent change
Leverage factor:	164%
Underlier percent change:	(final level – initial level) / initial level
Downside threshold level:	, which is 60% of the initial level
Absolute underlier return:	The absolute value of the underlier percent change. For example, a -5.00% underlier percent change will result in a +5.00% absolute underlier return.
Absolute return participation rate:	100%
Performance factor:	final level / initial level
CUSIP:	61779PZZ1
ISIN:	US61779PZZ16
Listing:	The securities will not be listed on any securities exchange.

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Morgan Stanley Finance LLC

Dual Directional Trigger PLUS

Principal at Risk Securities

Estimated Value of the Securities

The original issue price of each security is $1,000. This price includes costs associated with issuing, selling, structuring and hedging the securities, which are borne by you, and, consequently, the estimated value of the securities on the pricing date will be less than $1,000. Our estimate of the value of the securities as determined on the pricing date will be within the range specified on the cover hereof and will be set forth on the cover of the final pricing supplement.

What goes into the estimated value on the pricing date?

In valuing the securities on the pricing date, we take into account that the securities comprise both a debt component and a performance-based component linked to the underlier. The estimated value of the securities is determined using our own pricing and valuation models, market inputs and assumptions relating to the underlier, instruments based on the underlier, volatility and other factors including current and expected interest rates, as well as an interest rate related to our secondary market credit spread, which is the implied interest rate at which our conventional fixed rate debt trades in the secondary market.

What determines the economic terms of the securities?

In determining the economic terms of the securities, we use an internal funding rate, which is likely to be lower than our secondary market credit spreads and therefore advantageous to us. If the issuing, selling, structuring and hedging costs borne by you were lower or if the internal funding rate were higher, one or more of the economic terms of the securities would be more favorable to you.

What is the relationship between the estimated value on the pricing date and the secondary market price of the securities?

The price at which MS & Co. purchases the securities in the secondary market, absent changes in market conditions, including those related to the underlier, may vary from, and be lower than, the estimated value on the pricing date, because the secondary market price takes into account our secondary market credit spread as well as the bid-offer spread that MS & Co. would charge in a secondary market transaction of this type and other factors. However, because the costs associated with issuing, selling, structuring and hedging the securities are not fully deducted upon issuance, to the extent that MS & Co. may buy or sell the securities in the secondary market during the amortization period specified herein, absent changes in market conditions, including those related to the underlier, and to our secondary market credit spreads, it would do so based on values higher than the estimated value. We expect that those higher values will also be reflected in your brokerage account statements.

MS & Co. may, but is not obligated to, make a market in the securities, and, if it once chooses to make a market, may cease doing so at any time.

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Morgan Stanley Finance LLC

Dual Directional Trigger PLUS

Principal at Risk Securities

Hypothetical Examples

Hypothetical Payoff Diagram

The payoff diagram below illustrates the payment at maturity for a range of hypothetical performances of the underlier over the term of the securities, based on the following terms:

Stated principal amount:	$1,000 per security
Leverage factor:	164%
Absolute return participation rate:	100%
Downside threshold level:	60% of the initial level
Minimum payment at maturity:	None
Hypothetical Payoff Diagram

￭Upside Scenario. If the final level is greater than the initial level, investors will receive the stated principal amount plus 164% of the appreciation of the underlier over the term of the securities.

oIf the underlier appreciates 10%, investors will receive $1,164 per security, or 116.40% of the stated principal amount.

￭Absolute Return Participation Scenario. If the final level is equal to or less than the initial level but is greater than or equal to the downside threshold level, investors will receive the stated principal amount plus a positive return equal to (i) the absolute value of the percentage decline in the level of the underlier multiplied by (ii) the absolute return participation rate. Under these circumstances, the payment at maturity will effectively be limited to a positive return of 40% per security.

oIf the underlier depreciates 10%, investors will receive $1,100 per security, or 110% of the stated principal amount.

￭Downside Scenario. If the final level is less than the downside threshold level, investors will receive an amount that is significantly less than the stated principal amount, based on a 1% loss of principal for each 1% decline in the level of the underlier. There is no minimum payment at maturity, and investors could lose their entire initial investment in the securities.

oIf the underlier depreciates 85%, investors will lose 85% of their principal and receive only $150 per security at maturity, or 15% of the stated principal amount.

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Morgan Stanley Finance LLC

Dual Directional Trigger PLUS

Principal at Risk Securities

Risk Factors

This section describes the material risks relating to the securities. For further discussion of these and other risks, you should read the section entitled “Risk Factors” in the accompanying product supplement and prospectus. We also urge you to consult with your investment, legal, tax, accounting and other advisers in connection with your investment in the securities.

Risks Relating to an Investment in the Securities

￭The securities do not guarantee the return of any principal and do not pay interest. The terms of the securities differ from those of ordinary debt securities in that they do not guarantee the repayment of any principal and do not pay interest. If the final level is less than the downside threshold level, the payout at maturity will be an amount in cash that is significantly less than the stated principal amount of each security, and you will lose an amount proportionate to the full decline in the level of the underlier over the term of the securities. There is no minimum payment at maturity on the securities, and, accordingly, you could lose your entire initial investment in the securities.

￭Any positive return on the securities that is based on the depreciation of the underlier is effectively capped. Any positive return on the securities that is based on the depreciation of the underlier will be capped, because the absolute return participation feature is operative only if the level of the underlier has not declined below the downside threshold level on the observation date. Any decline in the level of the underlier beyond the downside threshold level will result in a significant loss, rather than a positive return, on your initial investment in the securities.

￭The amount payable on the securities is not linked to the value of the underlier at any time other than the observation date. The final level will be based on the closing level of the underlier on the observation date, subject to postponement for non-trading days and certain market disruption events. Even if the value of the underlier appreciates prior to the observation date but then drops by the observation date, the payment at maturity may be significantly less than it would have been had the payment at maturity been linked to the value of the underlier prior to such drop. Although the actual value of the underlier on the stated maturity date or at other times during the term of the securities may be higher than the closing level of the underlier on the observation date, the payment at maturity will be based solely on the closing level of the underlier on the observation date.

￭The market price of the securities may be influenced by many unpredictable factors. Several factors, many of which are beyond our control, will influence the value of the securities in the secondary market and the price at which MS & Co. may be willing to purchase or sell the securities in the secondary market. We expect that generally the value of the underlier at any time will affect the value of the securities more than any other single factor. Other factors that may influence the value of the securities include:

othe volatility (frequency and magnitude of changes in value) of the underlier;

ointerest and yield rates in the market;

ogeopolitical conditions and economic, financial, political, regulatory or judicial events that affect the underlier or equity markets generally;

othe availability of comparable instruments;

othe composition of the underlier and changes in the component securities of the underlier;

othe time remaining until the securities mature; and

oany actual or anticipated changes in our credit ratings or credit spreads.

Some or all of these factors will influence the price that you will receive if you sell your securities prior to maturity. Generally, the longer the time remaining to maturity, the more the market price of the securities will be affected by the other factors described above. For example, you may have to sell your securities at a substantial discount from the stated principal amount if, at the time of sale, the closing level of the underlier is at, below or not sufficiently above the downside threshold level, or if market interest rates rise.

You can review the historical closing levels of the underlier in the section of this document called “Historical Information.” You cannot predict the future performance of the underlier based on its historical performance. The value of the underlier may be, and has recently been, volatile, and we can give you no assurance that the volatility will lessen. There can be no assurance that the final level will be greater than or equal to the downside threshold level so that you do not suffer a significant loss on your initial investment in the securities.

￭The securities are subject to our credit risk, and any actual or anticipated changes to our credit ratings or credit spreads may adversely affect the market value of the securities. You are dependent on our ability to pay all amounts due on the securities, and, therefore, you are subject to our credit risk. The securities are not guaranteed by any other entity. If we default on our obligations under the securities, your investment would be at risk and you could lose some or all of your investment. As a result, the market value of the securities prior to maturity will be affected by changes in the market’s view of our creditworthiness.

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Morgan Stanley Finance LLC

Dual Directional Trigger PLUS

Principal at Risk Securities

Any actual or anticipated decline in our credit ratings or increase in the credit spreads charged by the market for taking our credit risk is likely to adversely affect the market value of the securities.

￭As a finance subsidiary, MSFL has no independent operations and will have no independent assets. As a finance subsidiary, MSFL has no independent operations beyond the issuance and administration of its securities and will have no independent assets available for distributions to holders of MSFL securities if they make claims in respect of such securities in a bankruptcy, resolution or similar proceeding. Accordingly, any recoveries by such holders will be limited to those available under the related guarantee by Morgan Stanley and that guarantee will rank pari passu with all other unsecured, unsubordinated obligations of Morgan Stanley. Holders will have recourse only to a single claim against Morgan Stanley and its assets under the guarantee. Holders of securities issued by MSFL should accordingly assume that in any such proceedings they would not have any priority over and should be treated pari passu with the claims of other unsecured, unsubordinated creditors of Morgan Stanley, including holders of Morgan Stanley-issued securities.

￭The rate we are willing to pay for securities of this type, maturity and issuance size is likely to be lower than the rate implied by our secondary market credit spreads and advantageous to us. Both the lower rate and the inclusion of costs associated with issuing, selling, structuring and hedging the securities in the original issue price reduce the economic terms of the securities, cause the estimated value of the securities to be less than the original issue price and will adversely affect secondary market prices. Assuming no change in market conditions or any other relevant factors, the prices, if any, at which dealers, including MS & Co., may be willing to purchase the securities in secondary market transactions will likely be significantly lower than the original issue price, because secondary market prices will exclude the issuing, selling, structuring and hedging-related costs that are included in the original issue price and borne by you and because the secondary market prices will reflect our secondary market credit spreads and the bid-offer spread that any dealer would charge in a secondary market transaction of this type as well as other factors.

The inclusion of the costs of issuing, selling, structuring and hedging the securities in the original issue price and the lower rate we are willing to pay as issuer make the economic terms of the securities less favorable to you than they otherwise would be.

However, because the costs associated with issuing, selling, structuring and hedging the securities are not fully deducted upon issuance, to the extent that MS & Co. may buy or sell the securities in the secondary market during the amortization period specified herein, absent changes in market conditions, including those related to the underlier, and to our secondary market credit spreads, it would do so based on values higher than the estimated value, and we expect that those higher values will also be reflected in your brokerage account statements.

￭The estimated value of the securities is determined by reference to our pricing and valuation models, which may differ from those of other dealers and is not a maximum or minimum secondary market price. These pricing and valuation models are proprietary and rely in part on subjective views of certain market inputs and certain assumptions about future events, which may prove to be incorrect. As a result, because there is no market-standard way to value these types of securities, our models may yield a higher estimated value of the securities than those generated by others, including other dealers in the market, if they attempted to value the securities. In addition, the estimated value on the pricing date does not represent a minimum or maximum price at which dealers, including MS & Co., would be willing to purchase your securities in the secondary market (if any exists) at any time. The value of your securities at any time after the date of this document will vary based on many factors that cannot be predicted with accuracy, including our creditworthiness and changes in market conditions. See also “The market price of the securities may be influenced by many unpredictable factors” above.

￭The securities will not be listed on any securities exchange and secondary trading may be limited. The securities will not be listed on any securities exchange. Therefore, there may be little or no secondary market for the securities. MS & Co. may, but is not obligated to, make a market in the securities and, if it once chooses to make a market, may cease doing so at any time. When it does make a market, it will generally do so for transactions of routine secondary market size at prices based on its estimate of the current value of the securities, taking into account its bid/offer spread, our credit spreads, market volatility, the notional size of the proposed sale, the cost of unwinding any related hedging positions, the time remaining to maturity and the likelihood that it will be able to resell the securities. Even if there is a secondary market, it may not provide enough liquidity to allow you to trade or sell the securities easily. Since other broker-dealers may not participate significantly in the secondary market for the securities, the price at which you may be able to trade your securities is likely to depend on the price, if any, at which MS & Co. is willing to transact. If, at any time, MS & Co. were to cease making a market in the securities, it is likely that there would be no secondary market for the securities. Accordingly, you should be willing to hold your securities to maturity.

￭As discussed in more detail in the accompanying product supplement, investing in the securities is not equivalent to investing in the underlier(s).

￭The U.S. federal income tax consequences of an investment in the securities are uncertain. There is no direct legal authority regarding the proper U.S. federal income tax treatment of the securities, and significant aspects of the tax treatment of the securities are uncertain. You should review carefully the section entitled “United States Federal Income Tax Considerations” herein, in combination with the section entitled “United States Federal Income Tax Considerations” in the accompanying product supplement, and consult your tax adviser regarding the U.S. federal income tax consequences of an investment in the securities.

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Morgan Stanley Finance LLC

Dual Directional Trigger PLUS

Principal at Risk Securities

Risks Relating to the Underlier(s)

￭Because your return on the securities will depend upon the performance of the underlier(s), the securities are subject to the following risk(s), as discussed in more detail in the accompanying product supplement.

oHigher future prices of a futures contract to which the underlier is linked relative to its current prices may adversely affect the value of the underlier and the value of the securities.

oSuspensions or disruptions of market trading in futures markets could adversely affect the value of the securities.

oLegal and regulatory changes could adversely affect the return on and value of the securities.

￭Adjustments to the S&P 500® Futures Excess Return Index could adversely affect the value of the securities. As the underlying index publisher for the S&P 500® Futures Excess Return Index, S&P® Dow Jones Indices LLC can make methodological changes that could change the value of such underlying index. Any of these actions could adversely affect the value of the securities. An underlying index publisher has no obligation to consider your interests in calculating or revising an underlying index. An underlying index publisher may discontinue or suspend calculation or publication of an underlying index at any time. In these circumstances, MS & Co., as the calculation agent, will have the sole discretion to substitute a successor index that is comparable to the discontinued underlying index. MS & Co. could have an economic interest that is different than that of investors in the securities insofar as, for example, MS & Co. is permitted to consider indices that are calculated and published by MS & Co. or any of its affiliates.

Risks Relating to Conflicts of Interest

In engaging in certain activities described below and as discussed in more detail in the accompanying product supplement, our affiliates may take actions that may adversely affect the value of and your return on the securities, and in so doing they will have no obligation to consider your interests as an investor in the securities.

￭The calculation agent, which is a subsidiary of Morgan Stanley and an affiliate of MSFL, will make determinations with respect to the securities. As calculation agent, MS & Co. will make any determinations necessary to calculate any payment(s) on the securities. Moreover, certain determinations made by MS & Co., in its capacity as calculation agent, may require it to exercise discretion and make subjective judgments, which may adversely affect your return on the securities. In addition, MS & Co. has determined the estimated value of the securities on the pricing date.

￭Hedging and trading activity by our affiliates could potentially adversely affect the value of the securities.

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Morgan Stanley Finance LLC

Dual Directional Trigger PLUS

Principal at Risk Securities

Historical Information

S&P 500® Futures Excess Return Index Overview

Bloomberg Ticker Symbol: SPXFP

The S&P 500® Futures Excess Return Index is an equity futures index that measures the performance of the nearest maturing quarterly E-mini S&P 500 futures contract (its “futures contract”) trading on the Chicago Mercantile Exchange. The underlying index publisher with respect to the S&P 500® Futures Excess Return Index is S&P® Dow Jones Indices LLC, or any successor thereof. E-mini S&P 500 futures contracts are U.S. dollar-denominated futures contracts based on the performance of the S&P 500® Index (its “reference index”). For additional information about the S&P 500® Index and how it is calculated and maintained, see “S&P® U.S. Indices—S&P 500® Index” in the accompanying index supplement. For additional information about the S&P 500® Futures Excess Return Index, see the information set forth under “Annex A—S&P 500® Futures Excess Return Index” below.

The closing level of the underlier on October 10, 2025 was 537.95. The following graph sets forth the daily closing levels of the underlier for the period noted below. We obtained the historical information presented in this document from Bloomberg Financial Markets, without independent verification. The underlier has at times experienced periods of high volatility. You should not take the historical closing levels of the underlier as an indication of its future performance, and no assurance can be given as to the closing level of the underlier at any time.

Underlier Daily Closing Levels

January 1, 2020 to October 10, 2025

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Morgan Stanley Finance LLC

Dual Directional Trigger PLUS

Principal at Risk Securities

Additional Terms of the Securities

Please read this information in conjunction with the terms on the cover of this document.

Additional Terms:
If the terms described herein are inconsistent with those described in the accompanying product supplement, index supplement or prospectus, the terms described herein shall control.
Denominations:	$1,000 per security and integral multiples thereof
Dual Directional Trigger PLUS:	The accompanying product supplement refers to these Dual Directional Trigger PLUS as the “securities.”
Amortization period:	The 6-month period following the issue date
Trustee:	The Bank of New York Mellon
Calculation agent:	Morgan Stanley & Co. LLC (“MS & Co.”)

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Morgan Stanley Finance LLC

Dual Directional Trigger PLUS

Principal at Risk Securities

Additional Information About the Securities

Additional Information:
Minimum ticketing size:	$1,000 / 1 security
United States federal income tax considerations:	You should review carefully the section in the accompanying product supplement entitled “United States Federal Income Tax Considerations.” The following discussion, when read in combination with that section, constitutes the full opinion of our counsel, Davis Polk & Wardwell LLP, regarding the material U.S. federal income tax consequences of owning and disposing of the securities. Generally, this discussion assumes that you purchased the securities for cash in the original issuance at the stated issue price and does not address other circumstances specific to you, including consequences that may arise due to any other investments relating to an underlier. You should consult your tax adviser regarding the effect any such circumstances may have on the U.S. federal income tax consequences of your ownership of a security. In the opinion of our counsel, which is based on current market conditions, it is reasonable to treat the securities for U.S. federal income tax purposes as prepaid financial contracts that are “open transactions,” as described in the section entitled “United States Federal Income Tax Considerations—Tax Consequences to U.S. Holders—Securities Treated as Prepaid Financial Contracts that are Open Transactions” in the accompanying product supplement. There is uncertainty regarding this treatment, and the IRS or a court might not agree with it. Moreover, because this treatment of the securities and our counsel’s opinion are based on market conditions as of the date of this preliminary pricing supplement, each is subject to confirmation on the pricing date. A different tax treatment could be adverse to you. Generally, if this treatment is respected, (i) you should not recognize taxable income or loss prior to the taxable disposition of your securities (including upon maturity or an earlier redemption, if applicable) and (ii) the gain or loss on your securities should be treated as capital gain or loss. We do not plan to request a ruling from the IRS regarding the treatment of the securities. An alternative characterization of the securities could materially and adversely affect the tax consequences of ownership and disposition of the securities, including the timing and character of income recognized. In addition, the U.S. Treasury Department and the IRS have requested comments on various issues regarding the U.S. federal income tax treatment of “prepaid forward contracts” and similar financial instruments and have indicated that such transactions may be the subject of future regulations or other guidance. Furthermore, members of Congress have proposed legislative changes to the tax treatment of derivative contracts. Any legislation, Treasury regulations or other guidance promulgated after consideration of these issues could materially and adversely affect the tax consequences of an investment in the securities, possibly with retroactive effect. Non-U.S. Holders. As discussed under “United States Federal Income Tax Considerations—Tax Consequences to Non-U.S. Holders—Dividend Equivalents under Section 871(m) of the Code” in the accompanying product supplement, Section 871(m) of the Internal Revenue Code and Treasury regulations promulgated thereunder (“Section 871(m)”) generally impose a 30% withholding tax on dividend equivalents paid or deemed paid to Non-U.S. Holders with respect to certain financial instruments linked to U.S. equities or indices that include U.S. equities. The Treasury regulations, as modified by an IRS notice, exempt financial instruments issued prior to January 1, 2027 that do not have a “delta” of one. Based on certain determinations made by us, we expect that Section 871(m) will not apply to the securities with regard to Non-U.S. Holders. Our determination is not binding on the IRS, and the IRS may disagree with this determination. If necessary, further information regarding the potential application of Section 871(m) will be provided in the final pricing supplement for the securities. We will not be required to pay any additional amounts with respect to U.S. federal withholding taxes. You should consult your tax adviser regarding the U.S. federal income tax consequences of an investment in the securities, including possible alternative treatments, as well as tax consequences arising under the laws of any state, local or non-U.S. taxing jurisdiction.
Additional considerations:	Client accounts over which Morgan Stanley, Morgan Stanley Wealth Management or any of their respective subsidiaries have investment discretion are not permitted to purchase the securities, either directly or indirectly.
Supplemental information regarding plan of distribution; conflicts of interest:	Selected dealers and their financial advisors will collectively receive from the agent, MS & Co., a fixed sales commission of $32.50 for each security they sell. In addition, selected dealers and their financial advisors will receive a structuring fee of up to $9 for each security from the agent or its affiliates. MS & Co. is an affiliate of MSFL and a wholly owned subsidiary of Morgan Stanley, and it and other affiliates of ours expect to make a profit by selling, structuring and, when applicable, hedging the securities.

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Morgan Stanley Finance LLC

Dual Directional Trigger PLUS

Principal at Risk Securities

MS & Co. will conduct this offering in compliance with the requirements of FINRA Rule 5121 of the Financial Industry Regulatory Authority, Inc., which is commonly referred to as FINRA, regarding a FINRA member firm’s distribution of the securities of an affiliate and related conflicts of interest. MS & Co. or any of our other affiliates may not make sales in this offering to any discretionary account. See “Plan of Distribution (Conflicts of Interest)” and “Use of Proceeds and Hedging” in the accompanying product supplement.

Where you can find more information:

Morgan Stanley and MSFL have filed a registration statement (including a prospectus, as supplemented by the product supplement and the index supplement) with the Securities and Exchange Commission (the “SEC”) for the offering to which this communication relates. You should read the prospectus in that registration statement, the product supplement, the index supplement and any other documents relating to this offering that MSFL and Morgan Stanley have filed with the SEC for more complete information about Morgan Stanley and this offering. When you read the accompanying index supplement, please note that all references in such supplement to the prospectus dated November 16, 2023, or to any sections therein, should refer instead to the accompanying prospectus dated April 12, 2024 or to the corresponding sections of such prospectus, as applicable. You may get these documents without cost by visiting EDGAR on the SEC website at www.sec.gov. Alternatively, MSFL, Morgan Stanley, any underwriter or any dealer participating in the offering will arrange to send you the prospectus, the index supplement and the product supplement if you so request by calling toll-free 1-(800)-584-6837. Terms used but not defined in this document are defined in the product supplement, in the index supplement or in the prospectus. Each of the product supplement, the index supplement and the prospectus can be accessed via the hyperlinks set forth on the cover of this document. “Performance Leveraged Upside SecuritiesSM” and “PLUSSM” are our service marks.

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Morgan Stanley Finance LLC

Dual Directional Trigger PLUS

Principal at Risk Securities

Annex A—S&P 500® Futures Excess Return Index

The S&P 500® Futures Excess Return Index (the “SPXFP Index”) is an equity futures index that measures the performance of the nearest maturing quarterly E-mini S&P 500 futures contract (its “futures contract”) trading on the Chicago Mercantile Exchange (the “CME”). The underlying index publisher with respect to the SPXFP Index is S&P® Dow Jones Indices LLC (“S&P®”), or any successor thereof. E-mini S&P 500 futures contracts are U.S. dollar-denominated futures contracts based on the performance of the S&P 500® Index (its “reference index”). For additional information about the S&P 500® Index and how it is calculated and maintained, see “S&P® U.S. Indices—S&P 500® Index” in the accompanying index supplement.

The SPXFP Index is the excess return version of the S&P 500 Futures Index, which measures the performance of the nearest maturing quarterly E-mini S&P 500 futures contract trading on the CME. The SPXFP Index includes a provision for the replacement of the E-mini S&P 500 futures contract as the contract approaches maturity (also referred to as “rolling” or “the roll”). This replacement occurs over a one-day rolling period every March, June, September and December, effective after the close of trading five business days preceding the last trading date of the E-mini S&P 500 futures contract.

S&P® is a joint venture between S&P® Global, Inc. (majority owner) and CME Group Inc. (minority owner), owner of CME Group Index Services LLC. The SPXFP Index is reported by Bloomberg under the ticker symbol “SPXFP.” All information contained in this document regarding the SPXFP Index has been derived from publicly available information, without independent verification.

E-Mini S&P 500 Futures Contract

The SPXFP Index is constructed from the front-quarter E-mini S&P 500 futures contract. Futures contracts are contracts that legally obligate the holder to buy or sell an asset at a predetermined delivery price during a specified future time period. The futures contract is rolled forward once a quarter, effective after the close of trading five business days prior to expiration.

The E-mini S&P 500 futures (“ES”) contracts are U.S. dollar-denominated futures contracts, based on the S&P 500® Index, traded on the CME, representing a contract unit of $50 multiplied by the reference index, measured in dollars and cents per index point. The ES contracts are listed for the nearest twenty-one consecutive quarters, for each March, June, September and December. Trading of the ES contracts terminates at 9:30 A.M. Eastern time on the third Friday of the contract month. The daily settlement prices of the ES contracts are based on trading activity in the relevant contract (and in the case of a lead month also being the expiry month, together with trading activity on lead month-second month spread contracts) on the CME during a specified settlement period. The final settlement price of ES contracts is based on the opening prices of the component stocks in the reference index, determined on the third Friday of the contract month. For more information about the reference index, see “S&P® U.S. Indices—S&P 500® Index” in the accompanying index supplement.

SPXFP Index Calculation

The SPXFP Index, calculated from the price change of the futures contract, reflects the excess return of the S&P 500 Futures Index. The level of the SPXFP Index on a trading day is calculated as follows:

IndexERd = IndexERd-1 × (1 + CDRd)

where:

IndexERd-1	=	The Excess Return Index level on the preceding business day, defined as any date on which the index is calculated
CDRd	=	The Contract Daily return, defined as:
	where:
		t	=	The business day on which the calculation is made
		TDW0t	=	Total Dollar Weight Obtained on t, defined as: CRW1t-1 × DCRP1t + CRW2t-1 × DCRP2t
		TDWIt-1	=	Total Dollar Weight Invested on the business day preceding t, defined as: CRW1t-1 × DCRP1t-1 + CRW2t-1 × DCRP2t-1
		CRW1	=	The contract roll weight of the first nearby contract expiration
		CRW2	=	The contract roll weight of the roll in contract expiration
		DCRP t	=	The Daily Contract Reference Price (the official closing price per futures contract, as designated by the relevant exchange) of the futures contract

The SPXFP Index is calculated on an excess return basis, meaning that the level of the SPXFP Index is determined by its weighted return reduced by the return that could be earned on a notional cash deposit at the notional interest rate, which is a rate equal to the federal funds rate.

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Morgan Stanley Finance LLC

Dual Directional Trigger PLUS

Principal at Risk Securities

Overview of Futures Markets

Futures contracts are traded on regulated futures exchanges, in the over-the-counter market and on various types of electronic trading facilities and markets. As of the date of this pricing supplement, the futures contract is an exchange-traded futures contract. A futures contract provides for a specified settlement month in which the cash settlement is made by the seller (whose position is therefore described as “short”) and acquired by the purchaser (whose position is therefore described as “long”).

No purchase price is paid or received on the purchase or sale of a futures contract. Instead, an amount of cash or cash equivalents must be deposited with the broker as “initial margin.” This amount varies based on the requirements imposed by the exchange clearing houses, but it may be lower than 5% of the notional value of the contract. This margin deposit provides collateral for the obligations of the parties to the futures contract.

By depositing margin, which may vary in form depending on the exchange, with the clearing house or broker involved, a market participant may be able to earn interest on its margin funds, thereby increasing the total return that it may realize from an investment in futures contracts. However, the SPXFP Index is not a total return index and does not reflect interest that could be earned on funds notionally committed to the trading of futures contracts.

At any time prior to the expiration of a futures contract, a trader may elect to close out its position by taking an opposite position on the exchange on which the trader obtained the position, subject to the availability of a liquid secondary market. This operates to terminate the position and fix the trader’s profit or loss. Futures contracts are cleared through the facilities of a centralized clearing house and a brokerage firm that is a member of the clearing house. Futures exchanges may adopt rules and take other actions that affect trading, including imposing speculative position limits, maximum price fluctuations and trading halts and suspensions and requiring liquidation of contracts in certain circumstances.

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The securities are not sponsored, endorsed, sold or promoted by S&P®. S&P® makes no representation or warranty, express or implied, to the owners of the securities or any member of the public regarding the advisability of investing in securities generally or in the securities particularly or the ability of the SPXFP Index to track general stock market performance. The SPXFP Index is determined, composed and calculated by S&P® without regard to us or the securities. S&P® has no obligation to take our needs or the needs of the owners of the securities into consideration in determining, composing or calculating the SPXFP Index. S&P® is not responsible for and has not participated in the determination of the timing of, prices at, or quantities of the securities to be issued or in the determination or calculation of the equation by which the securities are to be converted into cash. S&P® has no obligation or liability in connection with the administration, marketing or trading of the securities.

S&P® DOES NOT GUARANTEE THE ACCURACY AND/OR THE COMPLETENESS OF THE SPXFP INDEX, THE REFERENCE INDEX OR ANY DATA INCLUDED THEREIN. S&P® MAKES NO WARRANTY, EXPRESS OR IMPLIED, AS TO RESULTS TO BE OBTAINED BY MORGAN STANLEY, OWNERS OF THE SECURITIES, OR ANY OTHER PERSON OR ENTITY FROM THE USE OF THE SPXFP INDEX, THE REFERENCE INDEX OR ANY DATA INCLUDED THEREIN. S&P® MAKES NO EXPRESS OR IMPLIED WARRANTIES, AND HEREBY EXPRESSLY DISCLAIMS ALL WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR USE WITH RESPECT TO THE SPXFP INDEX, THE REFERENCE INDEX OR ANY DATA INCLUDED THEREIN. WITHOUT LIMITING ANY OF THE FOREGOING, IN NO EVENT SHALL S&P® HAVE ANY LIABILITY FOR ANY SPECIAL, PUNITIVE, INDIRECT OR CONSEQUENTIAL DAMAGES (INCLUDING LOST PROFITS), EVEN IF NOTIFIED OF THE POSSIBILITY OF SUCH DAMAGES.

“Standard & Poor’s®,” “S&P®,” “S&P 500®,” “Standard & Poor’s 500” and “500” are trademarks of Standard and Poor’s Financial Services LLC.

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FAQ

What is Morgan Stanley (MS) offering in this 424(b)(2) filing?

Dual Directional Trigger PLUS notes linked to the S&P 500 Futures Excess Return Index, maturing on November 5, 2031, with principal at risk.

How does the 164% leverage work on these MS notes?

If the final index level is above the initial level, the maturity payment adds 164% of the index’s percentage gain to the $1,000 principal.

What is the downside threshold and what happens if it’s breached?

The threshold is 60% of the initial level; if the final level falls below it, investors lose 1% of principal per 1% index decline.

Is there a cap on positive returns when the index declines?

Yes. If the index is at/above the threshold but below the initial level, the absolute-return feature is effectively capped at a 40% gain.

What are the pricing and fees for these MS notes?

Issue price is $1,000, estimated value about $935.20, agent commission $32.50 per note, and proceeds to the issuer $967.50 per note.

Will these MS notes be listed on an exchange?

No. They will not be listed, and secondary market making by MS & Co. is discretionary.

What are the key dates for the MS Dual Directional Trigger PLUS?

Observation date is October 31, 2031; maturity date is November 5, 2031.