X0306 4 2015-06-02 0 0000811596 KAISER ALUMINUM CORP KALU 0001213324 OSBORNE ALFRED E JR C/O KAISER ALUMINUM CORP. 27422 PORTOLA PARKWAY SUITE 200 FOOTHILL RANCH CA 92610 1 0 0 0 Common Stock, par value $0.01 per share 2015-06-02 4 A 0 1158 0.00 A 12894 D Common Stock, par value $0.01 per share 2015-06-02 4 A 0 731 81.98 A 13625 D Common Stock, par value $0.01 per share 3500 I By Keogh Plan Common Stock, par value $0.01 per share 200 I By son Common Stock, par value $0.01 per share 500 I By the Rahnasto/Osborne Revocable Trust U/A DTD 11/07/1999 Grant to the reporting person of restricted stock under the Kaiser Aluminum Corporation Amended and Restated 2006 Equity and Performance Incentive Plan. All restrictions will lapse on June 2, 2016. Stock received by the reporting person under the Kaiser Aluminum Corporation Amended and Restated 2006 Equity and Performance Incentive Plan at such person's election in lieu of all or a portion of the reporting person's annual cash retainer for serving as a member of the Board of Directors of Kaiser Aluminum Corporation, lead independent director or chair of a committee of the Board of Directors. Equal to the average of the closing prices of the Issuer's common stock as reported by the Nasdaq Stock Market, LLC for the twenty trading days prior to June 2, 2015. /s/ Cherrie I. Tsai, with power of attorney for Alfred E. Osborne, Jr. 2015-06-04