EXHIBIT 11 EXHIBIT 11 BIOGEN, INC. and SUBSIDIARIES Computation of Earnings Per Share (unaudited) (in thousands, except per share amounts) Three Months Nine Months Ended Sep. 30, Ended Sep 30, 1994 1993 1994 1993 Primary earnings per share Weighted average number of shares outstanding . . . . . . . 33,021 31,983 32,660 31,893 Shares deemed outstanding from the assumed exercise of stock options and warrants . . . . . . - - 2,354 - - 2,655 -------- -------- -------- -------- Total . . . . . . . . . . . . . . 33,021 34,337 32,660 34,548 ======== ======== ======== ======== Net income (loss) . . . . . . . . $(26,421) $ 11,275 $(14,581) $ 28,179 ======== ======== ======== ======== Primary earnings (loss) per share of common stock. . . . . . $ (0.80) $ 0.33 $ (0.45) $ 0.82 ======== ======== ======== ======== Fully diluted earnings per share (a) Weighted average number of shares outstanding . . . . . . . 33,021 31,983 32,660 31,893 Shares deemed outstanding from the assumed exercise of stock options and warrants . . . . . . - - 3,090 - - 3,090 -------- -------- -------- -------- Total . . . . . . . . . . . . . . 33,021 35,073 32,660 34,983 ======== ======== ======== ======== Net income (loss) . . . . . . . . $(26,421) $ 11,275 $(14,581) $ 28,179 ======== ======== ======== ======== Fully diluted earnings (loss) per share of common stock. . . . $ (0.80) $ 0.32 $ (0.45) $ 0.81 ======== ======== ======== ======== (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%.