X0303 4 2010-10-13 0001408198 MSCI Inc. MSCI 0001416753 Retelny Gary MSCI INC. 88 PINE STREET NEW YORK NY 10005 0 1 0 0 Head of Strategy & Bus. Dev. Class A Common Stock 2010-10-13 4 S 0 10000 35.69 D 151451 D This transaction was executed in multiple trades at prices ranging from $35.59 to $35.72. The price reported above reflects the weighted average purchase price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or security holder of the issuer full information regarding the number of shares and prices at which each transaction was effected. /s/ Gary Retelny 2010-10-14