8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (date of earliest event reported):

May 24, 2011

Cabot Microelectronics Corporation

(Exact name of registrant as specified in its charter)

Delaware	000-30205	36-4324765
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification)

870 Commons Drive, Aurora, Illinois	60504
(Address of principal executive offices)	(Zip Code)

(630) 375-6631

(Registrant’s telephone number, including area code)

Not applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o   Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o   Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o   Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o   Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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Item 8.01                     Other Events

On May 24, 2011, Cabot Microelectronics Corporation issued a press release entitled “Cabot Microelectronics Corporation to Participate in D.A. Davidson Third Annual Technology Investor Forum,” a copy of which is attached as Exhibit 99.1 and incorporated herein by reference.  Related investor materials are available in the Investor Relations section of its corporate website at www.cabotcmp.com.

This information is being furnished pursuant to Item 8.01 of Form 8-K and shall not be deemed “filed” for purposes of Section 18 of the Securities and Exchange Act of 1934, as amended (the “Exchange Act”), or incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

Item 9.01                      Financial Statements and Exhibits.

(c)	Exhibits
	The following exhibit is being furnished, not filed, herewith pursuant to  Item 8.01 of Form 8-K:
	99.1           Press release, dated May 24, 2011, entitled “Cabot Microelectronics Corporation to Participate in D.A. Davidson Third Annual Technology Investor Forum.”

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	CABOT MICROELECTRONICS CORPORATION
Date: May 24, 2011	By:	/s/ WILLIAM S. JOHNSON
		William S. Johnson
		Vice President and Chief Financial Officer
		[Principal Financial Officer]

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INDEX TO EXHIBITS

Exhibit Number	Title
99.1	Press release, dated May 24, 2011, entitled “Cabot Microelectronics Corporation to Participate in D.A. Davidson Third Annual Technology Investor Forum.”

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EX-99.1

EXHIBIT 99.1

PRESS RELEASE

 Contact:

 Trisha Tuntland

 Investor Relations Manager

 Cabot Microelectronics Corporation

 (630) 499-2600

CABOT MICROELECTRONICS CORPORATION TO PARTICIPATE IN

D.A. DAVIDSON THIRD ANNUAL TECHNOLOGY INVESTOR FORUM

AURORA, Illinois – May 24, 2011 – Cabot Microelectronics Corporation (NASDAQ: CCMP), the world's leading supplier of chemical mechanical planarization (CMP) polishing slurries and a growing CMP pad supplier to the semiconductor industry, today announced that it is scheduled to participate in the D.A. Davidson Third Annual Technology Investor Forum in New York on June 1, 2011.  For more information, or to arrange a meeting with management, please contact your D.A. Davidson representative, or Trisha Tuntland of Cabot Microelectronics at investor_relations@cabotcmp.com.

Related investor materials are available on the company’s website at www.cabotcmp.com or by clicking here.

http://phx.corporate-ir.net/External.File?item=UGFyZW50SUQ9OTUyOTN8Q2hbpGRJRD0tMXxUeXBIPTM=&t=1

ABOUT CABOT MICROELECTRONICS CORPORATION

Cabot Microelectronics Corporation, headquartered in Aurora, Illinois, is the world's leading supplier of CMP polishing slurries and growing CMP pad supplier to the semiconductor industry. The company's products play a critical role in the production of advanced semiconductor devices, enabling the manufacture of smaller, faster and more complex devices by its customers. The company's mission is to create value by developing reliable and innovative solutions, through close customer collaboration, that solve today's challenges and help enable tomorrow's technology. Since becoming an independent public company in 2000, the company has grown to approximately 975 employees on a global basis. For more information about Cabot Microelectronics Corporation, visit www.cabotcmp.com or contact Trisha Tuntland, Investor Relations Manager at 630-499-2600.