X0206 3 2013-02-12 0 0000913077 AFFYMETRIX INC AFFX 0001323221 Weber David A C/O AFFYMETRIX, INC. 3420 CENTRAL EXPRESSWAY SANTA CLARA CA 95051 0 1 0 0 EVP, Commercial Operations Common Stock 55750 D Option to Purchase Common Stock 3.86 2018-12-15 Common Stock 90000 D Option to Purchase Common Stock 3.84 2020-02-14 Common Stock 50000 D This Form 3 does not include 50,000 performance-based restricted stock untits granted on February 14, 2013. These shares will be reported on subsequent Form 4s if and when the performance criteria are met. Includes (1) 25,000 restricted stock units granted on December 15, 2011 and 30,000 restricted stock units granted on February 14, 2013 (each restricted stock unit grant vests in equal annual installments over four years from the grant date) and (2) 750 shares purchased through the Employee Stock Purchase Plan of Affymetrix, Inc. on November 14, 2012. Stock option becomes exercisable in equal annual installments over four years from the grant date of December 15, 2011. Stock option becomes exercisable in equal annual installments over four years from the grant date of February 14, 2013. /s/ Siang H. Chin, Attorney-in-Fact for David Weber 2013-02-19