Share Plans (Tables)

12 Months Ended

Dec. 31, 2012

Stock Option Activity

The following table summarizes stock option activity under all plans for the year ended December 31, 2012:

Options outstanding	Shares		Weighted- average exercise price		Weighted- average remaining contractual life	Aggregate intrinsic value
Beginning balance	7,837,696		$	32.50
Grants assumed in Merger	2,791,678		28.04
Granted	834,918		36.05
Exercised	(2,740,778	)	29.60
Forfeited	(83,994	)	32.64
Expired	(234,774	)	38.88
Ending balance	8,404,746		$	32.13	5.3	$	128,370,687
Options exercisable as of December 31, 2012	6,931,146		$	31.99	4.7	$	105,758,171
Options expected to vest as of December 31, 2012	1,422,898		$	32.92	8.1	$	21,763,738

Assumptions Used in Calculating Estimated Fair Value of Stock Option Award

We estimated the fair value of each stock option award on the date of grant using a Black-Scholes option pricing model, modified for dividends and using the following weighted average assumptions:

	December 31
	2012				2011		2010
	Assumed in Merger		Granted by Pentair plans		Granted by Pentair plans		Granted by Pentair plans
Risk-free interest rate	0.02 - 0.68%		0.96	%	1.51	%	2.45	%
Expected dividend yield	2.12	%	2.48	%	2.32	%	2.30	%
Expected share price volatility	33.00	%	36.50	%	35.50	%	35.00	%
Expected term (years)	0.1 - 5.1		5.7		5.5		5.5

Restricted Share and Restricted Stock Award Activity

The following table summarizes restricted share and restricted stock activity under all plans for the year ended December 31, 2012:

Restricted shares and restricted stock units outstanding	Shares		Weighted average grant date fair value
Beginning balance	1,250,082		$	30.49
Grants assumed in Merger	978,756		38.85
Granted	863,310		41.56
Vested	(1,420,511	)	33.17
Forfeited	(78,359	)	37.22
Ending balance	1,593,278		$	38.97