Ownership Submission
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 *
Naman Ananth
   2. Issuer Name and Ticker or Trading Symbol
CABOT MICROELECTRONICS CORP [CCMP] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
VP & Chief Technology Officer
(Last)
(First)
(Middle)
C/O CABOT MICROELECTRONICS CORPORATION, 870 COMMONS DRIVE		 3. Date of Earliest Transaction (Month/Day/Year)
12/10/2018
(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 12/10/2018   S   1,500 D $ 97.0367 13,230.3808 D  
Common Stock 12/10/2018   M   4,450 A $ 44.1 17,680.3808 D  
Common Stock 12/10/2018   S(1)   4,450 D $ 97.0881 13,230.3808 D  
Common Stock 12/10/2018   M   1,589 A $ 46.45 14,819.3808 D  
Common Stock 12/10/2018   S(1)   1,589 D $ 97.0881 13,230.3808 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) $ 44.1 12/10/2018   M     4,450 12/03/2014(2) 12/03/2023 Common Stock 4,450 $ 0 0 D  
Stock Options (Right to Buy) $ 46.45 12/10/2018   M     1,589 12/03/2015(3) 12/03/2024 Common Stock 1,589 $ 0 6,411 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Naman Ananth
C/O CABOT MICROELECTRONICS CORPORATION
870 COMMONS DRIVE
AURORA, IL 60504		       VP & Chief Technology Officer  

Signatures

 /s/ H. Carol Bernstein (Power of Attorney)   12/10/2018
**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 of, and taxes related to, cashless exercise of stock options.
(2) 2013 (FY14) Non-Qualified Stock Option Grant Vesting Schedule: 25% 12/03/2014, 25% 12/03/2015, 25% 12/03/2016, 25% 12/03/2017.
(3) 2014 (FY15) Non-Qualified Stock Option Grant Vesting Schedule: 25% 12/03/2015, 25% 12/03/2016, 25% 12/03/2017, 25% 12/03/2018.

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