EXHIBIT 11 PENTAIR, INC. AND SUBSIDIARIES COMPUTATION OF EARNINGS PER COMMON AND COMMON EQUIVALENT SHARE Nine Months Quarter Ended September 30 September 30 1996 1995 1996 1995 INCOME ($ thousands) Net income $52,187 $59,200 $18,578 $15,300 Preferred dividend requirements 3,816 3,981 1,268 1,324 Earnings available to common and common equivalent shares - Primary 48,371 55,219 17,310 13,976 Preferred dividends assuming conversion of Preferred Stock: Series 1988 711 741 233 244 Series 1990 3,105 3,240 1,035 1,080 Tax benefit on preferred ESOP dividend eliminated due to conversion into common (1,010) (947) (327) (301) Tax benefit on ESOP dividend assuming con- version to common, at common dividend rate 488 366 158 116 Earnings available for common and common equivalent shares - Diluted $51,665 $58,619 $18,409 $15,115 SHARES (thousands) Weighted average number of shares outstanding during the period 37,433 36,754 37,573 36,902 Shares issuable on exercise of stock options less shares repurchaseable from proceeds 482 484 464 476 Common and Common Equivalent Shares - Primary 37,915 37,238 38,037 37,378 Shares issuable on conversion of: $7.50 Callable Cumulative Convertible Preferred Stock, Series 1988 948 988 931 976 8% Callable Cumulative Voting Convertible Preferred Stock, Series 1990 3,882 4,120 3,825 4,044 Common and Common Equivalent Shares - Diluted 42,745 42,346 42,793 42,398 Earnings per Share: Primary Income from continuing operations $1.28 $1.04 $.46 $.38 Income from discontinued operations .00 .45 .00 .00 Net income $1.28 $1.49 $.46 $.38 Diluted Income from continuing operations $1.21 $.99 $.43 $.36 Income from discontinued operations .00 .40 .00 .00 Net income $1.21 $1.39 $.43 $.36