EXHIBIT 11 CLOSURE MEDICAL CORPORATION COMPUTATION OF PRO FORMA NET INCOME (LOSS) PER SHARE (Unaudited) (In thousands, except per share data) YEAR ENDED YEAR ENDED YEAR ENDED DECEMBER 31, DECEMBER 31, DECEMBER 31, 1996 1997 1998 ------- ------- ------- Weighted average common shares outstanding for the period - basic EPS 10,285 12,966 13,270 -------- ------- ------- Effect of dilutive stock options (a) - - - -------- ------- ------- Weighted average common shares outstanding for the period - diluted EPS (a) 10,285 12,966 13,270 -------- ------- ------- Net income (loss) $(16,814) $(6,829) $(4,773) ======== ======= ======= Net income (loss) per share - basic $ (1.63) $ (0.53) $ (0.36) ======== ======= ======= Net income (loss) per share - diluted $ (1.63) $ (0.53) $ (0.36) ======== ======= ======= (a) Diluted net loss per common share is computed using the weighted-average number of shares of common and common equivalent shares of stock options using the treasury stock method. Common equivalent shares consist of stock options using the treasury stock method. Common equivalent shares from stock options are excluded from the computation if their effect is antidilutive.