X0303 4 2010-05-05 0 0000319201 KLA TENCOR CORP KLAC 0001430600 Kirloskar Virendra A C/O KLA-TENCOR CORPORATION ONE TECHNOLOGY DRIVE MILPITAS CA 95035 0 1 0 0 SVP & Chief Accounting Officer Common Stock 2010-05-05 4 A 0 4000 A 11431 D Common Stock 2010-05-05 4 F 0 1489 33.04 D 9942 D Common Stock - Restricted Stock Units 38350 D On May 5, 2008, Mr. Kirloskar received a grant of restricted stock units ("RSUs") covering 8,000 shares of KLA-Tencor common stock. On May 5, 2010, Mr. Kirloskar vested in fifty percent (50%) of such RSUs. Pursuant to the terms of the May 5, 2008 RSU grant, 1,489 shares of KLA-Tencor common stock were automatically withheld at vesting to cover required tax withholding. The fair market value of KLA-Tencor common stock used for purposes of calculating the number of shares to be withheld was the closing price of KLA-Tencor common stock as reported on the NASDAQ Stock Market on such vesting date. Each RSU represents a contingent right to receive one share of KLA-Tencor common stock. Does not include performance-based RSUs, if any, held by the Reporting Person for which an assessment has not yet been made regarding the achievement of the applicable performance goals. Any such holdings will be reported on Form 4 within two business days of the date such assessment is made. Brian M. Martin as Attorney-in-Fact for Virendra A. Kirloskar 2010-05-06