1 Exhibit 11.1 ISOCOR STATEMENT OF COMPUTATION OF SHARES USED IN PER SHARE COMPUTATION (IN THOUSANDS) Three months ended Nine months ended ---------------------------- ------------------------------- September 30, September 30, September 30, September 30, 1996 1995 1996 1995 ------------- ------------- ------------- ------------- Computation of shares used in net income (loss) per share: Weighted average common shares outstanding . . . 9,271 1,651 6,789 1,664 Common equivalent shares attributable to stock options (treasury stock method) . . . . 1,181 485 1,158 173 Common equivalent shares attributable to redeemable preferred stock . . . . . . . . - 5,182 - 813 ------ ----- ----- ----- Shares used in per share calculation . . . . . . . . 10,452 7,318 7,947 2,650 ====== ===== ===== =====