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Multi-Asset Portfolio | Multi-Asset Portfolio

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Supplement [Text Block]

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January 29, 2013

Morgan Stanley Institutional Fund, Inc.

Supplement dated January 29, 2013 to the Morgan Stanley Institutional Fund, Inc. Prospectus dated May 23, 2012 of:

Multi-Asset Portfolio
(the "Portfolio")

Risk/Return [Heading]

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Multi-Asset Portfolio

Risk [Heading]

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The following is hereby added as the penultimate paragraph under the section of the Prospectus entitled "Portfolio Summary - Principal Risks:"

Risk Narrative [Text Block]

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•  Non-Diversified Risk. Because the Portfolio is non-diversified, it may be more susceptible to an adverse event affecting a portfolio investment than a diversified portfolio and a decline in the value of that instrument would cause the Portfolio's overall value to decline to a greater degree.

Risk Nondiversified Status [Text]

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Because the Portfolio is non-diversified, it may be more susceptible to an adverse event affecting a portfolio investment than a diversified portfolio and a decline in the value of that instrument would cause the Portfolio's overall value to decline to a greater degree.