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, Section 17(a) of the Public Utility Holding Company Act of 1935 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 * FULLER H LAURANCE   2. Issuer Name and Ticker or Trading Symbol CABOT MICROELECTRONICS CORP [CCMP] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) C/O CABOT MICROELECTRONICS CORPORATION, 870 COMMONS DRIVE 3. Date of Earliest Transaction (Month/Day/Year) 02/17/2012 (Street) AURORA, IL 60504 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 02/17/2012   M   15,000 A $ 45.49 32,000 D   Common Stock 02/17/2012   S(1)   13,539 D $ 50.4581 18,461 D   Common Stock 02/17/2012   M   7,500 A $ 45.49 25,961 D   Common Stock 02/17/2012   S(1)   6,770 D $ 50.4581 19,191 D   Common Stock 02/17/2012   M   7,500 A $ 38.34 26,691 D   Common Stock 02/17/2012   S(1)   5,705 D $ 50.4581 20,986 D   Common Stock 02/17/2012   M   10,000 A $ 42.44 30,986 D   Common Stock 02/17/2012   S(1)   8,421 D $ 50.4581 22,565 D   Common Stock 02/17/2012   M   10,000 A $ 32.02 32,565 D   Common Stock 02/17/2012   S(1)   6,354 D $ 50.4581 26,211 D

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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

Stock Options (Right to Buy)

$ 45.49

02/17/2012

M

15,000

06/17/2003(2)

06/17/2012

Common Stock

15,000

$ 0

0

D

Stock Options (Right to Buy)

$ 45.49

02/17/2012

M

7,500

06/17/2003

06/17/2012

Common Stock

7,500

$ 0

0

D

Stock Options (Right to Buy)

$ 38.34

02/17/2012

M

7,500

03/11/2004(3)

03/11/2013

Common Stock

7,500

$ 0

0

D

Stock Options (Right to Buy)

$ 42.44

02/17/2012

M

10,000

03/09/2005(4)(5)

03/09/2014

Common Stock

10,000

$ 0

0

D

Stock Options (Right to Buy)

$ 32.02

02/17/2012

M

10,000

03/08/2006(6)

03/08/2015

Common Stock

10,000

$ 0

0

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
FULLER H LAURANCE C/O CABOT MICROELECTRONICS CORPORATION 870 COMMONS DRIVE AURORA, IL 60504	X

Signatures

/s/ H. Carol Bernstein (Power of Attorney)		02/17/2012
**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)	Sale to cover exercise price for exercise of stock options.
(2)	Pursuant to Second Amended and Restated Equity Incentive Plan (EIP) and Compensation Committee action 9/27/04, grant agreement amended to provide that Vesting Schedule for Directors' Annual Non-Qualified Stock Option Award of 7,500 shares dated 6/17/02 is: 25% on 6/17/03 25% on 6/17/04 25% on 6/17/05 25% on 9/1/05
(3)	Pursuant to Second Amended and Restated Equity Incentive Plan (EIP) and Compensation Committee action 9/27/04, grant agreement amended to provide that Vesting Schedule is: 25% on 3/11/04 25% on 3/11/05 50% on 9/1/05
(4)	Pursuant to Second Amended and Restated Equity Incentive Plan (EIP) and Compensation Committee action 9/27/04, grant agreement amended to provide that Vesting Schedule is: 25% on 3/9/05 75% on 9/1/05
(5)	Vesting Schedule: 25% 3/9/2005 25% 3/9/2006 25% 3/9/2007 25% 3/9/2008
(6)	Directors' Annual Non-Qualified Stock Option Award Vesting dates: 25% 3/8/06, 25% 3/8/07, 25% 3/8/08, 25% 3/8/09

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