# EDGAR Filing Document

**Accession Number:** 0000836487
**File Stem:** 0001133228-26-007605
**Filing Date:** 2026-4
**Character Count:** 43743
**Document Hash:** fba34006e613f31c42cd5b4174d26c5b
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001133228-26-007605.hdr.sgml**: 20260430

**ACCESSION NUMBER**: 0001133228-26-007605

**CONFORMED SUBMISSION TYPE**: 497K

**PUBLIC DOCUMENT COUNT**: 4

**FILED AS OF DATE**: 20260430

**DATE AS OF CHANGE**: 20260430

**EFFECTIVENESS DATE**: 20260430

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MORGAN STANLEY INSTITUTIONAL FUND INC
- **CENTRAL INDEX KEY:** 0000836487

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** MD
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 497K
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 033-23166
- **FILM NUMBER:** 26927120

**BUSINESS ADDRESS:**
- **STREET 1:** 1585 BROADWAY
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10036
- **BUSINESS PHONE:** 800-548-7786

**MAIL ADDRESS:**
- **STREET 1:** 1585 BROADWAY
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10036

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MORGAN STANLEY DEAN WITTER INSTITUTIONAL FUND INC
- **DATE OF NAME CHANGE:** 19990329

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** MORGAN STANLEY INSTITUTIONAL FUND INC
- **DATE OF NAME CHANGE:** 19920703

## Series and Classes Contracts Data

### Vitality Portfolio (Series ID: S000074797)

| Class ID   | Class Name   | Ticker Symbol   |
|:---|:---|:---|
| C000233002 | Class I      | MSVDX           |
| C000233003 | Class A      | MSVEX           |
| C000233004 | Class C      | MSVMX           |
| C000233005 | Class R6     | MSVOX           |

![](sp17318img002.jpg) <br>

**Morgan Stanley Institutional** **Fund, Inc.**

Vitality Portfolio

**Summary Prospectus** **\|** April 30, 2026<br>

---

| | | | |
|:---|:---|:---|:---|
| **Share Class and Ticker Symbols** | **Share Class and Ticker Symbols** | **Share Class and Ticker Symbols** | **Share Class and Ticker Symbols** |
| **Class I** | **Class A** | **Class C** | **Class R6** |
| MSVDX | MSVEX | MSVMX | MSVOX |

---

Before you invest, you may want to review the Fund's statutory prospectus ("Prospectus"), which contains more information about the Fund and its risks. You can find the Fund's Prospectus and other information about the Fund, including the Statement of Additional Information ("SAI") and the most recent Annual and Semi-Annual Reports to Shareholders ("Shareholder Reports"), online at www.morganstanley.com/im/MSIFVitalityPortfolio. You can also get this information at no cost by calling toll-free 1-866-414-6349 or by sending an e-mail request to orders@mysummaryprospectus.com. The Fund's Prospectus and SAI, both dated April 30, 2026 (as may be supplemented from time to time), are incorporated by reference into this Summary Prospectus.

**Investment Objective**

The Vitality Portfolio (the "Fund") seeks long-term capital appreciation.

**Fees and Expenses**

The table below describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. **You may pay** **fees other than the fees and expenses of the Fund, such as brokerage commissions and other fees charged by financial** **intermediaries, which are not reflected in the tables and examples below.**

For purchases of Class A shares, you may qualify for a sales charge discount if the cumulative net asset value per share ("NAV") of Class A shares of the Fund being purchased in a single transaction, together with the NAV of any shares of the Fund and/or certain other Morgan Stanley Funds already held in Related Accounts (as defined in the section of the Prospectus entitled "Shareholder Information—Sales Charges Applicable to Purchases of Class A Shares") as of the date of the transaction, amounts to $50,000 or more. More information about this combined purchase discount and other discounts is available from your authorized financial intermediary, on page 86 of the Prospectus in the section entitled "Shareholder Information—Sales Charges Applicable to Purchases of Class A Shares" and in Appendix A attached to the Prospectus.

Class I shares may be available on brokerage platforms of firms that have agreements with the Fund's principal underwriter permitting such firms to (i) offer Class I shares solely when acting as an agent for the investor and (ii) impose on an investor transacting in Class I shares through such platforms a commission and/or other forms of compensation to the broker. Shares of the Fund are available in other share classes that have different fees and expenses.

![](sp17318img003.jpg) <br>

SU-MSIF-61

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Morgan Stanley Institutional Fund, Inc. Prospectus \| **Fund Summary**

Vitality Portfolio (Con't)

**Shareholder Fees** (fees paid directly from your investment)

---

| | | | | |
|:---|:---|:---|:---|:---|
|  | **Class I** | **Class A** | **Class C** | **Class R6** |
| Maximum sales charge (load) imposed on purchases (as a percentage of offering price) |  | 5.25% |  |  |
| Maximum deferred sales charge (load) (as a percentage based on the lesser of the offering price or NAV at redemption) |  | 1.00%<sup>1</sup> | 1.00%<sup>2</sup> |  |

---

---

| | |
|:---|:---|
| 1 | Investments in Class A shares that are not subject to any sales charges at the time of purchase are subject to a contingent deferred sales charge ("CDSC") of 1.00% that will be imposed if you sell your shares within 12 months, except for certain specific circumstances. See "Shareholder Information—How To Redeem Fund Shares" for further information about the CDSC waiver categories. |

---

2 The Class C CDSC is only applicable if you sell your shares within one year after the last day of the month of purchase. See "Shareholder Information—How To Redeem Fund Shares" for a complete discussion of the CDSC.

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

---

| | | | | |
|:---|:---|:---|:---|:---|
|  | **Class I** | **Class A** | **Class C** | **Class R6** |
| Advisory Fee | 0.75% | 0.75% | 0.75% | 0.75% |
| Distribution and/or Shareholder Service (12b-1) Fee |  | 0.25% | 1.00% |  |
| Other Expenses | 12.93% | 19.64% | 20.08% | 19.80% |
| Total Annual Fund Operating Expenses<sup>1</sup> | 13.68% | 20.64% | 21.83% | 20.55% |
| Fee Waiver and/or Expense Reimbursement<sup>1</sup> | 12.73% | 19.34% | 19.78% | 19.65% |
| Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement<sup>1</sup> | 0.95% | 1.30% | 2.05% | 0.90% |

---

---

| | |
|:---|:---|
| 1 | The Fund's "Adviser" and "Administrator," Morgan Stanley Investment Management Inc., has agreed to waive all or a portion of its advisory fee and/or reimburse the Fund so that Total Annual Fund Operating Expenses, excluding acquired fund fees and expenses (as applicable), certain investment related expenses, taxes, interest and other extraordinary expenses (including litigation), will not exceed 0.95% for Class I, 1.30% for Class A, 2.05% for Class C and 0.90% for Class R6. The fee waivers and/or expense reimbursements will continue for at least one year from the date of this Prospectus or until such time as the Board of Directors of Morgan Stanley Institutional Fund, Inc. (the "Company") acts to discontinue all or a portion of such waivers and/or reimbursements when it deems such action is appropriate. |

---

**Example**

The example below is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.

The example assumes that you invest $10,000 in the Fund, your investment has a 5% return each year and the Fund's operating expenses remain the same (except that the example incorporates the fee waiver and/or expense reimbursement arrangement for only the first year). After eight years, Class C shares of the Fund generally will convert automatically to Class A shares of the Fund. The example for Class C shares reflects the conversion to Class A shares after eight years. Please refer to the section of the Prospectus entitled "Shareholder Information—Conversion Features" for more information. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

---

| | | | | |
|:---|:---|:---|:---|:---|
| **If You SOLD Your Shares** | **If You SOLD Your Shares** | **If You SOLD Your Shares** | **If You SOLD Your Shares** | **If You SOLD Your Shares** |
|  | **1 Year** | **3 Years** | **5 Years** | **10 Years** |
| Class I | $97 | $2702 | $4874 | $8855 |
| Class A | $650 | $4097 | $6550 | $10017 |
| Class C | $308 | $3978 | $6586 | $10065 |
| Class R6 | $92 | $3731 | $6326 | $10008 |

---

---

| | | | | |
|:---|:---|:---|:---|:---|
| **If You HELD Your Shares** | **If You HELD Your Shares** | **If You HELD Your Shares** | **If You HELD Your Shares** | **If You HELD Your Shares** |
|  | **1 Year** | **3 Years** | **5 Years** | **10 Years** |
| Class I | $97 | $2702 | $4874 | $8855 |
| Class A | $650 | $4097 | $6550 | $10017 |
| Class C | $208 | $3978 | $6586 | $10065 |
| Class R6 | $92 | $3731 | $6326 | $10008 |

---

**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 Total Annual Fund Operating Expenses or in the Example, affect the

**2**

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Morgan Stanley Institutional Fund, Inc. Prospectus \| **Fund Summary**

Vitality Portfolio (Con't)

Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 27% of the average value of its portfolio.

**Principal Investment Strategies**

Under normal market conditions, the Adviser seeks to achieve the Fund's investment objective by investing primarily in securities of companies located in the United States that are principally engaged in the discovery, development, production, or distribution of products or services related to advances in healthcare. These companies include, but are not limited to, biotechnology, pharmaceuticals, medical equipment and supplies, healthcare technology, healthcare providers and services, and life sciences tools and services. The Fund may also allocate to industries related to the healthcare industry, but are not primarily engaged in the scientific advancement of healthcare. The allocation among these areas will vary depending on the relative potential the Adviser sees within each area and the outlook for the overall healthcare sector.

The Adviser emphasizes a bottom-up stock selection process, seeking attractive investments on an individual company basis. In selecting securities for investment, the Adviser typically invests in unique companies it believes have sustainable competitive advantages, strong research and development and productive new product flow, financial strength, and an attractive risk/reward profile. The Fund generally seeks investments in companies that are developing new and effective medicines, enabling novel and more efficient research and development efforts, as well as companies whose business models reduce costs or improve quality in healthcare systems. The Adviser typically focuses a significant portion of the Fund's investments in a limited number of issuers, which may be in the same industry, sector or geographic region.

The Adviser actively integrates sustainability into the investment process by using environmental, social and governance ("ESG") factors as a lens for additional fundamental research, which can contribute to investment decision-making. The Adviser seeks to understand how environmental and social initiatives within companies can create value by strengthening durable competitive advantages, creating growth opportunities, driving profitability and/or aligning with secular growth trends. The Adviser generally engages with company management teams to discuss their ESG practices, with the aim of identifying how sustainability themes present opportunities and risks that can be material to the value of the security over the long-term. Other aspects of the investment process include a proprietary, systematic evaluation of governance policies, specifically focusing on compensation alignment on long-term value creation. Although consideration of ESG factors is incorporated into the investment process, it is only one of many tools the Adviser utilizes to make investment decisions.

The Fund has a fundamental policy (i.e., one that cannot be changed without shareholder approval) of investing 25% or more of its total assets in the group of industries comprising the healthcare sector. Companies in the healthcare sector include biotechnology companies, pharmaceutical companies, medical equipment and supplies, healthcare technology, healthcare providers and services, and life sciences tools and services. Because the Fund is concentrated in the healthcare sector, it is less diversified than stock funds that invest in a broader range of industries and, therefore, the Fund could experience significant volatility.

The Fund will invest primarily in equity securities. The Fund may also invest in privately placed and restricted securities and special purpose acquisition companies ("SPACs").

The Adviser may invest up to 25% of the Fund's total assets in foreign securities, including emerging market securities and securities classified as American Depositary Receipts ("ADRs"), Global Depositary Receipts ("GDRs"), American Depositary Shares ("ADSs") or Global Depositary Shares ("GDSs"), foreign U.S. dollar-denominated securities that are traded on a U.S. exchange or local shares of non-U.S. issuers.

The equity securities in which the Fund primarily invests include common and preferred stocks, convertible securities and equity-linked securities, rights, warrants, depositary receipts, limited partnership interests, exchange-traded funds ("ETFs") and open-end and closed-end investment companies (including those which may be managed by the Adviser or its affiliates) and initial public offerings ("IPOs").

The Fund may use certain derivatives for the purposes of hedging, risk management, portfolio management or to earn income.

**Principal Risks**

There is no assurance that the Fund will achieve its investment objective, and you can lose money investing in this Fund. Investments in the Fund involve risks and you should not rely on the Fund as a complete investment program. The relative significance of each risk factor summarized below may change over time and you should review each risk factor carefully because any one or more of these risks may result in losses to the Fund. The principal risks of investing in the Fund include:

• **Equity Securities.** In
 general, prices of equity securities are more volatile than those of fixed-income securities. U.S. and foreign
 stock markets, and equity securities of individual issuers, have experienced periods of substantial price volatility in

**3**

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Morgan Stanley Institutional Fund, Inc. Prospectus \| **Fund Summary**

Vitality Portfolio (Con't)

the past and it is possible that they will do so again in the future. The prices of equity securities fluctuate, sometimes rapidly or widely, in response to activities specific to the issuer of the security as well as factors unrelated to the fundamental condition of the issuer, including general market, economic, political and public health conditions. During periods when equity securities experience heightened volatility, such as during periods of market, economic or financial uncertainty or distress, the Fund's investments in equity securities are subject to heightened risks.

The value of equity securities and related instruments decline in response to perceived or actual adverse changes in the economy, economic outlook or financial markets; deterioration in investor sentiment; inflation, interest rate, currency, and commodity price fluctuations; adverse geopolitical, social or environmental developments; issuer- and sector-specific considerations; unexpected trading activity among retail investors; and other factors. Market conditions affect certain types of equity securities to a greater extent than other types of equity securities. If the stock market declines, the value of the Fund's equity securities will also likely decline, which will result in a decrease in the value of your investment in the Fund. Although prices can rebound, there is no assurance that prices of the Fund's equity securities will return to previous levels.

• **Convertible Securities.** A
 convertible security is a bond, debenture, note, preferred stock, right, warrant or other security that
 may be converted into or exchanged for a prescribed amount of common stock or other security of the same or a different
 issuer or into cash within a particular period of time at a specified price or formula. To the extent that the Fund invests
 in convertible securities, and the convertible security's investment value is greater than its conversion value, its price will
 be likely to increase when interest rates fall and decrease when interest rates rise. If the conversion value exceeds the investment
 value, the price of the convertible security will tend to fluctuate directly with the price of the underlying security.

• **Private Placements and Restricted Securities.** The Fund's investments may include privately placed and restricted securities,
 which are generally subject to resale or transfer restrictions or prohibitions. Private placements and restricted securities
 may not be listed on an exchange and may have no active trading market. The Fund may be unable to dispose of privately
 placed and restricted securities promptly or may be able to sell privately placed and restricted securities only at disadvantageous
 times or prices, especially under adverse market or economic conditions or in the event of adverse changes
 in the financial condition of the issuer. There is no assurance that a liquid market will exist for privately placed and restricted
 securities and these securities could have the effect of increasing the level of Fund illiquidity. In addition, the market
 for certain investments deemed liquid at the time of purchase may become illiquid under adverse market or economic
 conditions. Restricted securities, including privately placed securities, may be difficult to value and may experience
 significant price volatility, and there is typically less information available about issuers of private placements and
 restricted securities and there is no assurance that the information obtained by the Adviser is reliable. Private placements
 and restricted securities may involve a high degree of business and financial risk and may result in substantial losses
 to the Fund.

• **Preferred Securities.** Preferred
 securities have many of the characteristics of and are subject to many of the risks associated
 with both fixed-income securities and equity securities. Preferred securities may pay fixed or adjustable rates of return.
 As with fixed-income securities, the market value of preferred securities is sensitive to changes in interest rates. Preferred
 securities generally decrease in value if interest rates rise and increase in value if interest rates fall. In addition, preferred
 securities are also subject to risks applicable generally to equity securities, such as issuer-specific and market risks.
 A company's preferred securities generally pay dividends only after the company makes required payments to holders
 of its bonds and other debt, so the value of preferred securities will usually react more strongly than bonds and other
 debt to actual or perceived changes in the company's financial condition or prospects.

• **ETFs.** Shares of ETFs have many of the same risks as direct investments in common stocks or bonds and their market value may
 differ from their NAV because the supply and demand in the market for ETF shares at any point in time is not always identical
 to the supply and demand in the market for the underlying securities. As a shareholder in an ETF, the Fund would bear
 its ratable share of that entity's expenses while continuing to pay its own investment management fees and other expenses.
 As a result, the Fund and its shareholders will, in effect, be absorbing fees at two levels. Furthermore, disruptions in
 the markets for the securities underlying ETFs purchased or sold by the Fund could result in losses on the Fund's investment
 in ETFs.

• **Healthcare Concentration Risk**.
 The Fund will concentrate its investments in the group of industries comprising the healthcare
 sector and, from time to time, may concentrate its investments in one or more individual industries in the group of
 industries comprising the healthcare sector. By concentrating its investments in the group of industries comprising the healthcare
 sector, the Fund has greater exposure to the potential adverse economic, regulatory, political and other changes affecting
 companies operating within such sector. The profitability of companies in the healthcare sector may be adversely affected
 by, among other things, extensive government regulation, restrictions on government reimbursement for medical expenses,
 rising costs of medical products and services, pricing pressure, costs associated with obtaining and protecting patents,
 product liability and other claims, an increased emphasis on outpatient services, changes in the demand for medical
 products and services, a limited number of products, industry innovation, changes in technologies and other market,
 economic and public health developments. To the extent that the Fund concentrates its investments in one or more

**4**

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Morgan Stanley Institutional Fund, Inc. Prospectus \| **Fund Summary**

Vitality Portfolio (Con't)

individual industries comprising the healthcare sector (such as, but not limited to, biotechnology, pharmaceuticals, medical equipment and supplies, healthcare technology, healthcare providers and services, and life sciences tools and services companies), the Fund will be particularly susceptible to the risks associated with such industry or industries.

Biotechnology, healthcare technology, pharmaceutical and life sciences tools and services companies are heavily dependent on patents and intellectual property rights and the loss or impairment of such rights will negatively impact a company's profitability. In addition, these companies are subject to the risk of new technologies and competition, large expenditures on research and development of products and services that may not prove commercially successful, regulations and restrictions imposed by the Food and Drug Administration, the Environmental Protection Agency, state and local governments and foreign regulatory authorities, and thin capitalization. Medical equipment and supply companies are heavily dependent on patent protection and may be subject to extensive litigation based on product liability and similar claims. In addition, medical equipment companies are subject to the risk that products can become obsolete due to industry innovation, changes in technology or other market developments, and may not receive necessary regulatory approvals to become commercially viable. Healthcare providers and services companies are particularly subject to certain risks, including restrictions on government reimbursement for medical expenses, an increased emphasis on outpatient services, rising costs of medical products and public health conditions.

• **IPOs.** The Fund may purchase shares issued as part of, or a short period after, a company's IPO, and may at times dispose of
 those shares shortly after their acquisition. The Fund's purchase of shares issued in IPOs exposes it to the risks associated with
 companies that have little operating history as public companies. The market for IPO issuers may be volatile, and share prices
 of newly-public companies have fluctuated significantly over short periods of time. IPOs may produce high, double- digit
 returns. Such returns are highly unusual and may not be sustainable.

• **SPACs.** A SPAC  is a publicly traded company that raises investment capital for the purpose of acquiring or merging with an existing
 company. An investment in a SPAC is subject to the risks that any proposed acquisition or merger may not obtain the
 requisite approval of SPAC shareholders, may require governmental or other approvals that it fails to obtain or that an acquisition
 or merger, once effected, may prove unsuccessful and lose value. In addition, among other conflicts of interest, the
 economic interests of the management, directors, officers and related parties of a SPAC can differ from the economic interests
 of public shareholders, which may lead to conflicts as they evaluate, negotiate and recommend business combination
 transactions to shareholders. An investment in a SPAC is also subject to the risk that a significant portion of the funds
 raised by the SPAC may be expended during the search for a target acquisition or merger.

• **Foreign and Emerging Market Securities.** Investments in foreign markets entail special risks, such as currency, political (including
 geopolitical), economic and market risks and heightened risks, that may result in losses to the Fund. There also may
 be greater market volatility, less reliable financial information, less stringent investor protections and disclosure standards,
 higher transaction and custody costs and risks, decreased market liquidity and less government and exchange regulation
 associated with investments in foreign markets. In addition, investments in certain foreign markets that have historically
 been considered stable may become more volatile and subject to increased risk due to developments and changing
 conditions in such markets. Moreover, the growing  interconnectivity of global economies and financial markets has
 increased the probability that adverse developments and conditions in one country or region will affect the stability of economies
 and financial markets in other countries or regions. Certain foreign markets may rely heavily on particular industries
 or foreign capital and are more vulnerable to diplomatic developments (including regional and global, military or other
 conflicts), the imposition of economic sanctions against a particular country or countries, organizations, companies, entities
 and/or individuals, changes in international trading patterns, trade barriers (including tariffs) and other protectionist or
 retaliatory measures. Investments in foreign markets may also be adversely affected by governmental interventions or other
 actions, such as the imposition of capital controls, nationalization of companies or industries, expropriation of assets or
 the imposition of punitive taxes. The governments of certain countries may prohibit or impose substantial restrictions on foreign
 investing in their capital markets or in certain sectors or industries. In addition, a foreign government may limit or cause
 delay in the convertibility or repatriation of its currency which would adversely affect the  U.S. dollar value and/or liquidity
 of investments denominated in that currency. Certain foreign investments may become less liquid and decline in value
 in response to market developments or adverse investor perceptions, or become illiquid after purchase by the Fund, particularly
 during periods of market, economic, political and social turmoil. When the Fund holds illiquid investments, its portfolio
 may be harder to value. The risks of investing in emerging market countries are greater than the risks associated with
 investments in foreign developed countries. Certain emerging market countries may be subject to less stringent requirements
 regarding accounting, auditing, financial reporting and record keeping and therefore, material information related
 to an investment may not be available or reliable. Certain
 emerging market or developing countries are among the largest
 debtors to commercial banks and foreign governments. The issuer or governmental authority that controls the repayment
 of sovereign debt may not be willing or able to repay the principal and/or pay interest when due in accordance with
 the terms of such obligations. In addition, foreign governments may default on their debt securities, which may require holders
 of such securities to participate in debt rescheduling or additional lending to defaulting governments. Moreover, there
 is no bankruptcy proceeding by which defaulted sovereign debt may be collected in whole or in part. In addition, the

**5**

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Morgan Stanley Institutional Fund, Inc. Prospectus \| **Fund Summary**

Vitality Portfolio (Con't)

Fund is limited in its ability to exercise its legal rights or enforce a counterparty's legal obligations in certain jurisdictions outside of the United States, in particular, in emerging market countries. In addition, the Fund's investments in foreign issuers may be denominated in foreign currencies and therefore, to the extent unhedged, the value of those investments will fluctuate with U.S. dollar exchange rates. Economic sanctions or other similar measures may be, and have been, imposed against certain countries, organizations, companies, entities and/or individuals. Economic sanctions and other similar measures could, among other things, effectively restrict or eliminate the Fund's ability to purchase or sell securities (in the sanctioned country and other markets), negatively impact the value or liquidity of the Fund's investments, significantly delay or prevent the settlement of the Fund's securities transactions, force the Fund to sell or otherwise dispose of investments at inopportune times or prices, or impair the Fund's ability to meet its investment objective or invest in accordance with its investment strategies.

• **Foreign Currency Forward Exchange Contracts.** To the extent the Fund seeks to hedge its foreign currency exposure by the
 use of foreign currency forward exchange contracts, the precise matching of the foreign currency forward exchange contract
 amounts and the value of the securities involved will not generally be possible because the future value of such securities
 in foreign currencies will change as a consequence of market movements in the value of those securities between the
 date on which the contract is entered into and the date it matures. There is additional risk that such transactions may reduce
 or preclude the opportunity for gain if the value of the currency should move in the direction opposite to the position taken
 and that foreign currency forward exchange contracts create exposure to currencies in which the Fund's securities are
 not denominated. The use of foreign currency forward exchange contracts involves the risks associated with derivatives and
 the risk of loss from the insolvency or bankruptcy of the counterparty to the contract or the failure of the counterparty to
 make payments or otherwise comply with the terms of the contract.

• **Derivatives.** Derivatives and other similar instruments that create synthetic exposure often are subject to risks similar to those
 of the underlying asset or instrument, including market risk, and may be subject to additional risks, including imperfect correlation
 between the value of the derivative and the underlying asset, risks of default by the counterparty to certain transactions,
 magnification of losses incurred due to changes in the market value of the securities, instruments, indices or interest
 rates to which the derivative instrument relates, risks that the transactions may not be liquid, risks arising from margin
 and payment requirements, risks arising from mispricing or valuation complexity and operational and legal risks. Certain
 derivative transactions may give rise to a form of leverage. Leverage magnifies the potential for gain and the risk of loss.

• **Small and Mid Cap Companies.** Investments in small and mid cap companies may involve greater risks than investments in larger,
 more established companies. The securities issued by small and mid cap companies may be less liquid and such companies
 may have more limited markets, financial resources and product lines, and may lack the depth of management of
 larger companies.

• **Liquidity.** The Fund may make investments that are less liquid, illiquid or restricted or that may become illiquid or less liquid in
 response to overall economic conditions or adverse investor perceptions, and which may entail greater risk than investments
 in other types of securities. These investments may be more difficult to value or sell, particularly in times of market
 turmoil, and there may be little trading in the secondary market available for particular securities.  If the Fund is forced
 to sell an illiquid or restricted security to fund redemptions or for other cash needs, it may be forced to sell the security
 at a loss or for less than its fair value and may be unable to sell the security at all.

• **Focused Investing.** Although
 the Fund is a diversified investment company under the Investment Company Act of 1940 (the "1940
 Act"), the Fund typically invests a significant portion of its portfolio in a limited number of issuers, which may be in the same
 industry, sector or geographic region. As a result, the Fund will be more susceptible to risks associated with, and negative
 events affecting those issuers, industries, sectors or geographic regions, and a decline in the value of a particular instrument
 may cause the Fund's overall value to be more volatile and decline to a greater degree than if the Fund were invested
 more widely.

• **Market and Geopolitical Risk.** The value of your investment in the Fund is based on the values of the Fund's investments, which
 change due to economic, geopolitical and other events that affect the U.S. and global markets generally, as well as those
 that affect or are perceived or expected to affect particular regions, countries, industries, companies, issuers, sectors, asset
 classes or governments. These types of events may be sudden and unexpected, and could adversely affect the value (or
 income generated by) and liquidity of the Fund's investments, which may in turn impact the Fund's ability to sell securities
 and/or its ability to meet redemptions. The risks associated with these developments may be magnified if certain social,
 political, economic and other conditions and events (such as war, natural disasters or events, epidemics and pandemics,
 terrorism, conflicts, social unrest, recessions, inflation, interest rate changes, supply chain disruptions and the threat
 and/or actual imposition of tariffs, trade barriers and other protectionist or retaliatory measures)  adversely interrupt or
 otherwise affect the global economy and financial markets. It is difficult to predict when events affecting the  U.S. or global
 financial markets or economies may occur, the effects that such events may have and the duration of those effects (which
 may last for extended periods). These types of events may negatively impact broad segments of businesses and populations
 and have a significant and rapid negative impact on the performance or value of the Fund's investments,

**6**

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Morgan Stanley Institutional Fund, Inc. Prospectus \| **Fund Summary**

Vitality Portfolio (Con't)

adversely affect and increase the volatility of the Fund's share price and exacerbate pre-existing risks to the Fund. The frequency and magnitude of resulting changes in the value of the Fund's investments cannot be predicted.

• **Active Management Risk.** In pursuing the Fund's investment objective, the Adviser has considerable leeway in deciding which
 investments to buy, hold or sell on a day-to-day basis, and which trading strategies to use. For example, the Adviser, in
 its discretion, may determine to use some permitted trading strategies while not using others. The success or failure of such
 decisions will affect the Fund's performance.

Please see "Additional Information About Fund Investment Strategies and Related Risks" in the Fund's prospectus for a more detailed description of risks of investing in the Fund. Shares of the Fund are not bank deposits and are not guaranteed or insured by the Federal Deposit Insurance Corporation or any other government agency.

**Performance Information**

The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund's Class I shares' performance from year-to-year and by showing how the Fund's average annual returns for the past one year period and since inception compare with those of a broad measure of market performance and one or more additional indexes. The additional index(es) in the table provides a means to compare the Fund's average annual total returns to a benchmark that the Adviser believes is representative of the Fund's investment universe. The performance of the other classes, which is shown in the table below, will differ because the classes have different ongoing fees. The Fund's returns in the table include the maximum applicable sales charge for Class A and Class C and assume you sold your shares at the end of each period (unless otherwise noted). 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 online at www.morganstanley.com/im or by calling toll-free 1-800-869-6397.

**Annual Total Returns—Calendar Years**

![](sp17318img001.jpg)

During the periods shown in the bar chart above:

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| | | |
|:---|:---|:---|
| **High Quarter** | 12/31/25 | 15.10% |
| **Low Quarter** | 06/30/22 | -24.06% |

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**Average Annual Total Returns**<br> (for the calendar periods ended December 31, 2025)

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| | | |
|:---|:---|:---|
|  | **Past**<br>**One Year** | **Since**<br>**Inception** |
| **Class I** (commenced operations on 12/31/2021) |  |  |
| Return Before Taxes | 15.10% | -8.88% |
| Return After Taxes on Distributions<sup>1</sup> | 14.45% | -9.28% |
| Return After Taxes on Distributions and Sale of Fund Shares | 8.99% | -6.68% |
| **Class A** (commenced operations on 12/31/2021) |  |  |
| Return Before Taxes | 8.66% | -10.39% |
| **Class C** (commenced operations on 12/31/2021) |  |  |
| Return Before Taxes | 12.63% | -9.89% |
| **Class R6** (commenced operations on 12/31/2021) |  |  |
| Return Before Taxes | 14.95% | -8.84% |
| Russell 3000® Index (reflects no deduction for fees, expenses or taxes)<sup>2</sup> | 17.15% | 10.22%<sup>3</sup> |
| Russell 3000® Health Care Net Index (reflects no deduction for fees, expenses or taxes)<sup>4</sup> | 14.02% | 2.98%<sup>3</sup> |

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**7**

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Morgan Stanley Institutional Fund, Inc. Prospectus \| **Fund Summary**

Vitality Portfolio (Con't)

1 These returns do not reflect any tax consequences from a sale of your shares at the end of each period.

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| | |
|:---|:---|
| 2 | The Russell 3000® Index measures the performance of the largest 3,000 U.S. companies designed to represent approximately 98% of the investable U.S. equity market. The Russell 3000® Index is constructed to provide a comprehensive, unbiased and stable barometer of the broad market and is completely reconstituted annually to ensure new and growing equities are included. It is not possible to invest directly in an index. |

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3 Since Inception reflects the inception date of the Fund.

4 The Russell 3000® Health Care Net Index is a capitalization-weighted index of companies involved in medical services or health care. It is not possible to invest directly in an index.

The after-tax returns shown in the table above are calculated using the historical highest individual federal marginal income tax rates during the period shown and do not reflect the impact of state and local taxes. After-tax returns for the Fund's other classes will vary from Class I shares' returns. Actual after-tax returns depend on the investor's tax situation and may differ from those shown, and after-tax returns are not relevant to investors who hold their Fund shares through tax deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns may be higher than before-tax returns due to an assumed benefit from capital losses that would have been realized had Fund shares been sold at the end of the relevant periods, as applicable.

**Fund Management**

**Adviser.** Morgan Stanley Investment Management Inc.

**Portfolio Managers.** The Fund is managed by members of Counterpoint Global. Information about the members jointly and primarily responsible for the day-to-day management of the Fund is shown below:

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| | | |
|:---|:---|:---|
| **Name** | **Title with Adviser** | **Date Began Managing Fund** |
| Anne Edelstein | Executive Director | December 2021 |
| Jenny Leeds, Ph.D. | Vice President | December 2021 |

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**Purchase and Sale of Fund Shares**

The minimum initial investment generally is $1 million for Class I shares and $1,000 for each of Class A and Class C shares of the Fund. To purchase Class R6 shares, an investor must meet a minimum initial investment of $5 million or be a defined contribution, defined benefit or other employer sponsored employee benefit plan, in each case provided that the plan trades through an intermediary that combines its clients' assets in a single omnibus account, whether or not such plan is qualified under the Internal Revenue Code of 1986, as amended (the "Code"), and in each case subject to the discretion of the Adviser. The minimum initial investment may be waived for certain investments. For more information, please refer to the section of the Prospectus entitled "Shareholder Information—Minimum Investment Amounts."

Shares of the Fund may be purchased or sold on any day the New York Stock Exchange ("NYSE") is open for business directly from the Fund by mail (c/o SS&C Global Investor and Distribution Solutions, Inc., P.O. Box 219804, Kansas City, MO 64121-9804), by telephone (1-800-869-6397) or by contacting an authorized third-party, such as a broker-dealer or other financial intermediary that has entered into a selling agreement with the Fund's "Distributor," Morgan Stanley Distribution, Inc. (each, a "Financial Intermediary"). In addition, you can sell Fund shares at any time by enrolling in a systematic withdrawal plan. If you sell Class A shares or Class C shares, your net sale proceeds are reduced by the amount of any applicable CDSC. For more information, please refer to the sections of the Prospectus entitled "Shareholder Information—How To Purchase Fund Shares" and "—How To Redeem Fund Shares."

**Tax Information**

The Fund intends to make distributions that may be taxed as ordinary income or capital gains, unless you are investing through a tax-deferred arrangement, such as a 401(k) plan or an individual retirement account.

**Payments to Broker-Dealers and Other Financial Intermediaries**

If you purchase shares of the Fund through a Financial Intermediary (such as a bank), the Adviser and/or the Distributor may pay the Financial Intermediary for the sale of Fund shares and related services. These payments, which may be significant in amount, may create a conflict of interest by influencing the Financial Intermediary and your salesperson to recommend the Fund over another investment. Ask your salesperson or visit your Financial Intermediary's web site for more information.

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