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):

November 14, 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 November 14, 2011, Cabot Microelectronics Corporation issued a press release entitled “Cabot Microelectronics Corporation Receives Ruling From Federal Circuit Court of Appeals.”  A copy of the press release is attached hereto as Exhibit 99.1 and incorporated herein by reference.

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 November 14, 2011, entitled “Cabot Microelectronics Corporation Receives Ruling From Federal Circuit Court of Appeals.”

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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: November 14, 2011	By:	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 November 14, 2011, entitled “Cabot Microelectronics Corporation Receives Ruling From Federal Circuit Court of Appeals.”

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EX-99.1

EXHIBIT 99.1

PRESS RELEASE

 Contact:

 Trisha Tuntland

 Manager of Investor Relations

 Cabot Microelectronics Corporation

 (630) 499-2600

CABOT MICROELECTRONICS CORPORATION RECEIVES

RULING FROM FEDERAL CIRCUIT COURT OF APPEALS

AURORA, IL, November 14, 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, announced today that the validity of its tungsten patents remains upheld as the company's appeal in its patent enforcement action against DuPont Air Products NanoMaterials, LLC (“DANano") has been decided with the Federal Circuit Court of Appeals affirming proceedings at the District Court.

“We continue to be pleased that the validity of all of our CMP patents at issue in the appeal, which are core patents for tungsten CMP applications, was confirmed through this legal process.  Although we are disappointed with the affirmation of the lower court's ruling regarding infringement, we view it as a narrow one that is not likely to fundamentally affect our leadership in tungsten CMP slurries, as it relates only to one aspect of the specific DA Nano products at issue in the case, and would not extend to other product variations,” said H. Carol Bernstein, Cabot Microelectronics’ Vice President, Secretary and General Counsel.  “We remain committed to the protection of our significant investment in patent-protected research and development, which is evident in our many tungsten CMP products that are world-renowned and in continued high demand for their excellence with respect to technology, quality, supply assurance, and overall cost of ownership.”

ABOUT CABOT MICROELECTRONICS CORPORATION

Cabot Microelectronics Corporation, headquartered in Aurora, Illinois, is the world's leading supplier of CMP polishing slurries and a 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 1,000 employees on a global basis.  For more information about Cabot Microelectronics Corporation, visit www.cabotcmp.com or contact Trisha Tuntland, Manager of Investor Relations at (630) 499-2600.

SAFE HARBOR STATEMENT

This news release may include statements that constitute “forward looking statements” within the meaning of federal securities regulations.  These forward-looking statements include statements related to:  future sales and operating results; company and industry growth, contraction or trends; growth or contraction of the markets in which the company participates; international events, regulatory or legislative activity, or various economic factors; product performance; the generation, protection and acquisition of intellectual property, and litigation related to such intellectual property; new product introductions; development of new products, technologies and markets; natural disasters; the acquisition of or investment in other entities; uses and investment of the company’s cash balance; and the construction and operation of facilities by Cabot Microelectronics Corporation.  These forward-looking statements involve a number of risks, uncertainties, and other factors, including those described from time to time in Cabot Microelectronics’ filings with the Securities and Exchange Commission (SEC), that could cause actual results to differ materially from those described by these forward-looking statements.  In particular, see “Risk Factors" in the company's quarterly report on Form 10-Q for the quarter ended June 30, 2011 and in the company’s annual report on Form 10-K for the fiscal year ended September 30, 2010, both filed with the SEC.  Cabot Microelectronics assumes no obligation to update this forward-looking information.