1 EXHIBIT 11 BIOGEN, INC AND SUBSIDIARIES Computation of Earnings Per Share (in thousands, except per share amounts) 1996 1995 1994 ------- ------- ------- Primary earnings(loss) per share Weighted average number of shares outstanding ............ 71,595 67,950 65,548 Shares deemed outstanding from the assumed exercise of stock options and warrants .......... 1,626 4,940 -- ------- ------- ------- Total .......................... 73,221 72,890 65,548 ======= ======= ======= Net income (loss) .............. $40,530 $ 5,660 $(4,897) ======= ======= ======= Primary earnings (loss) per Share of common stock ......... $ 0.55 $ 0.08 $ (0.07) ======= ======= ======= Fully diluted earnings (loss) per share (a) Weighted average number of shares ........................ 71,595 67,950 65,548 Shares deemed outstanding from the assumed exercise of stock options and warrants .......... 1,998 5,569 -- ------- ------- ------- Total .......................... 73,593 73,519 65,548 ======= ======= ======= Net income (loss) .............. $40,530 $ 5,660 $(4,897) ======= ======= ======= Fully diluted earnings(loss) per share of common stock ...... $ 0.55 $ 0.08 $ (0.07) ======= ======= ======= (a) This calculation is submitted in accordance with Regulation S-K item 601(b)(11) although not required by Footnote 2 to Paragraph 14 of APB Opinion No. 15 because it results in dilution of less than 3%.