FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
WALLACE RICHARD P
   2. Issuer Name and Ticker or Trading Symbol
KLA TENCOR CORP [KLAC] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
President and CEO
(Last)
(First)
(Middle)
C/O KLA-TENCOR CORPORATION, ONE TECHNOLOGY DRIVE		 3. Date of Earliest Transaction (Month/Day/Year)
02/17/2011
(Street)

MILPITAS, CA 95035		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 02/17/2011   M   16,500 A $ 45.25 72,234 D  
Common Stock 02/17/2011   S(1)   30,643 D $ 49.75 41,591 D  
Common Stock 02/17/2011   A   37,500 A (2) 79,091 D  
Common Stock 02/17/2011   F   16,330 (3) D $ 49.53 62,761 D  
Common Stock - Restricted Stock Units (4)               280,445 (5) D  

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Non-Qualified Stock Option (Right to Buy) $ 45.25 02/17/2011   M     16,500   (6) 10/02/2011 Common Stock 16,500 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
WALLACE RICHARD P
C/O KLA-TENCOR CORPORATION
ONE TECHNOLOGY DRIVE
MILPITAS, CA 95035		   X     President and CEO  

Signatures

 Brian M. Martin as Attorney-in-Fact for Richard P. Wallace   02/18/2011
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) These sales were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 15, 2009, as modified on December 14, 2010.
(2) On February 17, 2006, Mr. Wallace received a grant of restricted stock units ("RSUs") covering 75,000 shares of KLA-Tencor common stock. On February 17, 2011, Mr. Wallace vested in fifty percent (50%) of such RSUs.
(3) Pursuant to the terms of the February 17, 2006 RSU grant, 16,330 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.
(4) Each RSU represents a contingent right to receive one share of KLA-Tencor common stock.
(5) 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.
(6) Represents a stock option granted on October 2, 2001, granting the Reporting Person the right to purchase up to 16,500 shares of KLA-Tencor common stock. One forty-eighth (1/48) of the 16,500 shares subject to this stock option vested on the 13-month anniversary of the grant date and each monthly anniversary thereafter until October 2, 2006.

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