WD Extends Tender Offer for Komag Shares

LAKE FOREST, Calif.- Western Digital Corp. (NYSE: WDC) today announced that it is extending its previously announced tender offer for all outstanding shares of Komag, Incorporated (NASDAQ: KOMG), until 7:00 a.m., New York City time, on Wed., Sept. 5, 2007. The tender offer is being extended because the required waiting period under the antitrust laws of the People’s Republic of China is not expected to expire until the close of business, Beijing time, on Wed., Sept. 5, 2007. WD expects to complete the tender offer promptly following the expiration of this waiting period. WD filed the required notification with the Chinese authorities on July 25, 2007. As previously announced, the waiting period under the U.S. antitrust laws has already expired.

On July 11, 2007, WD, through its indirect wholly-owned subsidiary, State M Corporation, commenced a tender offer for all outstanding shares of common stock of Komag at a price of $32.25 per share net to the seller in cash without interest, less any required withholding taxes, upon the terms and subject to the conditions set forth in the Offer to Purchase dated July 11, 2007, as amended, and in the related Letter of Transmittal.

According to information provided by the depositary for the offer, as of 5:00 p.m., New York City time, on Thu., Aug. 2, 2007, an aggregate of approximately 2.6 million shares of Komag common stock, had been tendered into, and not withdrawn from, the offer.