X0202 3 2005-03-14 0 0000813347 KOMAG INC /DE/ KOMG 0001230572 HAMMACK WILLIAM 1710 AUTOMATION PARKWAY SAN JOSE CA 95131 0 1 0 0 VP, HUMAN RESOURCES Common Stock 4980 D Non-Qualified Stock Option (right to buy) 6.48 2003-10-07 2013-03-17 Common Stock 4375 D Non-Qualified Stock Option (right to buy) 13.16 2003-10-07 2013-07-25 Common Stock 2187 D Non-Qualified Stock Option (right to buy) 18.85 2005-03-15 2014-03-15 Common Stock 3750 D On 03/17/03, the Reporting Person was granted a 10,000 share option under the Issuer's Amended and Restated 2002 Qualified Stock Plan (the "2002 Plan"), of which one-fourth (1/4) of the shares vest on 10/07/03 and of which 1/36 of the remaining shares subject to such option vest on the 7th of each month thereafter, subject to the Reporting Person continuing to be a participant under the 2002 Plan on such dates. On 01/12/05, the Reporting Person commenced providing consulting services to the Issuer upon his termination of employment with the Issuer and continued as a participant under the 2002 Plan. On 03/14/05, the Reporting Person was re-hired as Vice President, Human Resources of the Issuer. On February 10, 2005, while not subject to the reporting requirements of Section 16 of the Securities Exchange Act of 1934, as amended ("Section 16"), the Reporting person exercised and sold 5,625 shares subject to this option. On 07/25/03, the Reporting Person was granted a 5,000 share option under the 2002 Plan, of which one-fourth (1/4) of the shares vest on 10/07/03 and of which 1/36 of the remaining shares subject to such option vest on the 7th of each month thereafter, subject to the Reporting Person continuing to be a participant under the 2002 Plan on such dates. On February 10, 2005, while not subject to the reporting requirements of Section 16 the Reporting person exercised and sold 2,813 shares subject to this option. On 03/15/04, the Reporting Person was granted a 3,750 share option under the 2002 Plan, of which one-fourth (1/4) of the shares vest on 03/15/05 and of which 1/36 of the remaining shares subject to such option vest on the 15th of each month thereafter, subject to the Reporting Person continuing to be a participant under the 2002 Plan on such dates. /s/ Jan Schwartz, Attorney-in-fact for William Hammack 2005-03-16