EXHIBIT 11 PENTAIR, INC. AND SUBSIDIARIES COMPUTATION OF EARNINGS PER COMMON AND COMMON EQUIVALENT SHARE Six Months Ended Quarter Ended June 30 June 30 1994 1993 1994 1993 INCOME ($ thousands) Net income $22,925 $19,282 11,825 $9,782 Preferred dividend requirements 2,731 3,397 1,365 1,397 Earnings available to common and common equivalent shares - Primary 20,194 15,885 10,460 8,385 Preferred dividends assuming conversion of Preferred Stock: Series 1987 - 620 - - Series 1988 511 527 255 272 Series 1990 <F1> 2,220 2,250 1,110 1,125 Tax benefit on preferred ESOP dividend eliminated due to conversion into common <F1> (527) (418) (263) (206) Tax benefit on ESOP dividend assuming con- version to common, at common dividend rate <F1> 184 139 92 68 Total <F1> $22,582 $19,003 $11,654 $9,644 Less: Effects dividends and tax benefits for anti-dilutive securities 2,109 1,056 Earnings for fully diluted computation $16,894 $8,588 SHARES (thousands) Weighted average number of shares outstanding during the period 18,181 17,234 18,194 18,076 Shares issuable on exercise of stock options less shares repurchaseable from proceeds 195 216 186 252 Common and Common Equivalent Shares - Primary 18,376 17,450 18,380 18,328 Shares issuable on conversion of: $1.50 Cumulative Convertible Preferred Stock, Series 1987 - 831 - - $7.50 Callable Cumulative Convertible Preferred Stock, Series 1988 511 525 510 521 8% Callable Cumulative Voting Convertible Preferred Stock, Series 1990 <F1> 2,117 2,130 2,113 2,128 Total <F1> 21,004 20,936 21,003 20,977 Less: Anti-dilutive securities 2,130 2,128 Common and common equivalent shares for fully dilutive computation 18,806 18,849 EARNINGS PER SHARE: Primary $1.10 $.91 $.57 $.46 Diluted $1.08 $.90 $.56 $.46 All share and per share data adjusted for 50% stock dividend in June 1993. <F1> This calculation is submitted in accordance with Regulation S-K Item 601(b)(11), although it is contrary to paragraph 40 of APB Opinion No. 15 because it produces an anti-dilutive result for the six months ended June 30, 1993.