UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

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¨ Preliminary Proxy Statement

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¨ Definitive Proxy Statement

x Definitive Additional Materials

¨ Soliciting Material Pursuant to Section 240.14a-12

MSCI Inc.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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(1) Amount Previously Paid:

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(4) Date Filed:

You are receiving this communication because you hold

shares in the above named company.

This is not a ballot. You cannot use this notice to vote

these shares. This communication presents only an

overview of the more complete proxy materials that are

available to you on the Internet. You may view the proxy

materials online at www.proxyvote.com or easily request a

paper copy (see reverse side).

We encourage you to access and review all of the

important information contained in the proxy materials

before voting.

*** Exercise Your Right to Vote ***

IMPORTANT NOTICE Regarding the Availability of Proxy Materials

See the reverse side of this notice to obtain

proxy materials and voting instructions.

Meeting Information

Meeting Type:

For holders as of:

Date: Time:

Location:

0000041845_1 R2.09.05.010

MSCI INC.

MSCI INC.

ATTN: CECILIA AZA

WALL STREET PLAZA

88 PINE STREET

NEW YORK, NY 10005

Annual Meeting

February 11, 2010

April 08, 2010 2:30 PM EDT

Davis Polk & Wardwell LLP

450 Lexington Avenue, 8th fl

New York, NY 10017

How To Vote

Please Choose One of The Following Voting Methods

Vote In Person: Many shareholder meetings have attendance requirements including, but not limited to, the possession

of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special

requirements for meeting attendance. At the Meeting you will need to request a ballot to vote these shares.

Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the 12 Digit Control Number available

and follow the instructions.

Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card.

Before You Vote

How to Access the Proxy Materials

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advisor. To facilitate timely delivery please make the request as instructed above on or before

Proxy Materials Available to VIEW or RECEIVE:

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How to Request and Receive a PAPER or E-MAIL Copy:

If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for

requesting a copy. Please choose one of the following methods to make your request:

1) BY INTERNET: www.proxyvote.com

2) BY TELEPHONE: 1-800-579-1639

3) BY E-MAIL*: sendmaterial@proxyvote.com

* If requesting materials by e-mail, please send a blank e-mail with the 12-Digit Control Number (located on the

following page) in the subject line.

0000041845_2 R2.09.05.010

1. Annual Report 2. Notice & Proxy Statement

Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment

advisor. Please make the request as instructed above on or before March 25, 2010 to facilitate timely delivery.

Voting items

0000041845_3 R2.09.05.010

The Board of Directors recommends you

vote FOR the following proposal(s):

1. Election of Directors

Nominees

01 Benjamin F. duPont

02 Henry A. Fernandez

03 Alice W. Handy

04 Catherine R. Kinney

05 Linda H. Riefler

06 George W. Siguler

07 Scott M. Sipprelle

08 Rodolphe M. Vallee

The Board of Directors recommends you

vote FOR the following proposal(s):

2 To ratify the appointment of Deloitte &

Touche LLP as independent auditor

NOTE: Such other business as may properly

come before the meeting or any adjournment

thereof.