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BACKGROUND AND BASIS OF PRESENTATION&lt;/font&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; TEXT-INDENT: 0pt"&gt;&lt;br /&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;&lt;font style="MARGIN-LEFT: 18pt"&gt;&lt;/font&gt;Cabot Microelectronics Corporation ("Cabot Microelectronics'', "the Company'', "us'', "we'' or "our'') supplies high-performance polishing slurries and pads used in the manufacture of advanced integrated circuit (IC) devices within the semiconductor industry, in a process called chemical mechanical planarization (CMP).&amp;#160;&amp;#160;CMP polishes surfaces at an atomic level, thereby enabling IC device manufacturers to produce smaller, faster and more complex IC devices with fewer defects.&amp;#160;&amp;#160;We develop, produce and sell CMP slurries for polishing many of the conducting and insulating materials used in IC devices, and also for polishing the disk substrates and magnetic heads used in hard disk drives.&amp;#160;&amp;#160;We also develop, manufacture and sell CMP polishing pads, which are used in conjunction with slurries in the CMP process.&amp;#160;&amp;#160;We also pursue other demanding surface modification applications through our Engineered Surface Finishes (ESF) business where we believe we can leverage our expertise in CMP consumables for the semiconductor industry to develop products for demanding polishing applications in other industries.&amp;#160;&amp;#160;For additional information, refer to Part 1, Item 1, &amp;#8220;Business&amp;#8221;, in our annual report on Form 10-K for the fiscal year ended September 30, 2010.&lt;/font&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; TEXT-INDENT: 0pt"&gt;&lt;br /&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;&lt;font style="MARGIN-LEFT: 18pt"&gt;&lt;/font&gt;The unaudited consolidated financial statements have been prepared by Cabot Microelectronics Corporation pursuant to the rules of the Securities and Exchange Commission (SEC) and accounting principles generally accepted in the United States of America.&amp;#160;&amp;#160;In the opinion of management, these unaudited consolidated financial statements include all normal recurring adjustments necessary for the fair presentation of Cabot Microelectronics&amp;#8217; financial position as of December 31, 2010, cash flows for the three months ended December 31, 2010, and December 31, 2009, and results of operations for the three months ended December 31, 2010, and December 31, 2009.&amp;#160;&amp;#160;The results of operations for the three months ended December 31, 2010 may not be indicative of results to be expected for future periods, including the fiscal year ending September 30, 2011.&amp;#160;&amp;#160;These unaudited consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes thereto included in Cabot Microelectronics&amp;#8217; annual report on Form 10-K for the fiscal year ended September 30, 2010.&amp;#160;&amp;#160;Certain reclassifications of prior fiscal year cash flow amounts have been made to conform to the current period presentation.&lt;/font&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; TEXT-INDENT: 0pt"&gt;&lt;br /&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;&lt;font style="MARGIN-LEFT: 18pt"&gt;&lt;/font&gt;The consolidated financial statements include the accounts of Cabot Microelectronics and its subsidiaries.&amp;#160;&amp;#160;All intercompany transactions and balances between the companies have been eliminated as of December 31, 2010.&lt;/font&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; TEXT-INDENT: 0pt"&gt;&lt;br /&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;&lt;font style="DISPLAY: inline; TEXT-DECORATION: underline"&gt;Results of Operations&lt;/font&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; TEXT-INDENT: 0pt"&gt;&lt;br /&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;&lt;font style="MARGIN-LEFT: 18pt"&gt;&lt;/font&gt;The results of operations for the quarter ended December 31, 2010 include certain adjustments to correct prior period amounts, which we have determined to be immaterial to the current period and the prior periods to which they relate.&amp;#160;&amp;#160;Collectively, these adjustments reduced net income for the first quarter of fiscal 2011 by $1,710 and diluted earnings per share by approximately $0.08.&amp;#160;&amp;#160;These adjustments relate to: (1) $1,474 ($1,014, net of tax) in employer-paid fringe benefits for required contributions to our 401(k) Plan, Supplemental Employee Retirement Plan, and non-United States statutory pension plans as a result of our annual payment pursuant to our fiscal 2010 annual incentive bonus program (AIP); (2) the reversal of a $497 deferred tax asset regarding certain share-based compensation expense which is not subject to such tax treatment; and (3) our under accrual of $290 ($199, net of tax) for payments made pursuant to the AIP as a result of the calculation of results against goals under the AIP.&lt;/font&gt;&lt;/div&gt;</NonNumbericText><NonNumericTextHeader>1. 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