1 EXHIBIT 11.1 ALTERA CORPORATION COMPUTATION OF EARNINGS PER SHARE (In thousands, except per share amounts) THREE MONTHS ENDED NINE MONTHS ENDED ------------------ ----------------- Sept. 30, Sept. 30, Sept. 30, Sept. 30, 1996 1995 1996 1995 --------- --------- --------- --------- PRIMARY: Weighted average shares outstanding 43,654 43,429 43,660 43,271 Net effect of dilutive stock options 1,921 2,423 2,134 2,256 ------- ------- ------- ------- Total 45,575 45,852 45,794 45,527 ======= ======= ======= ======= Net income $24,118 $23,729 $79,823 $58,458 ======= ======= ======= ======= Income per share $ 0.53 $ 0.52 $ 1.74 $ 1.28 ======= ======= ======= ======= FULLY DILUTED: Weighted average shares outstanding 43,654 43,430 43,660 43,271 Net effect of dilutive stock options 2,156 2,463 2,148 2,515 Assumed conversion of convertible subordinated 4,495 4,495 4,495 1,515 ------- ------- ------- ------- notes Total 50,305 50,388 50,303 47,301 ------- ------- ------- ------- Net income $24,118 $23,729 $79,823 $58,458 Add: Convertible subordinated notes interest, net 1,842 2,083 5,658 2,314 ------- ------- ------- ------- of income taxes Adjusted net income $25,960 $25,812 $85,481 $60,772 ======= ======= ======= ======= Income per share $ 0.52 $ 0.51 $ 1.70 $ 1.29 ======= ======= ======= =======