FORM 10-Q MARCH 31, 1996 EXHIBIT 11 American Power Conversion Corporation and Subsidiaries Computation of Earnings Per Share Three Months Ended March 31, 1996 1995 (Unaudited) Primary: Weighted average shares outstanding 93,419,328 92,450,296 Net effect of dilutive stock options and warrants based on the treasury stock method using the average market price 331,119 886,437 Total 93,750,447 93,336,733 Net Income $15,212,570 $18,269,813 Per share amount $0.16 $0.20 Fully Diluted: Weighted average shares outstanding 93,419,328 92,450,296 Net effect of dilutive stock options and warrants based on the treasury stock method using the period end market price 367,297 829,456 Total 93,786,625 93,279,752 Net income $15,212,570 $18,269,813 Per share amount $0.16 $0.20 15