7. Earnings Per Share

9 Months Ended

Sep. 30, 2011

7.EARNINGS PER SHARE

Basic earnings per share is computed by dividing net income attributable to Bio-Rad by the weighted average number of common shares outstanding for that period. Diluted earnings per share takes into account the effect of dilutive instruments, such as stock options and restricted stock, and uses the average share price for the period in determining the number of potential common shares that are to be added to the weighted average number of shares outstanding. Potential common shares are excluded from the diluted earnings per share calculation if the effect of including such securities would be anti-dilutive.

The weighted average number of common shares outstanding used to calculate basic and diluted earnings per share, and the anti-dilutive shares that are excluded from the diluted earnings per share calculation are as follows (in thousands):



	Three Months Ended		Nine Months Ended
	September 30,		September 30,
	2011	2010	2011	2010
Basic weighted average shares outstanding	28,072	27,697	27,997	27,616
Effect of potentially dilutive stock options and restricted stock awards	384	406	457	494
Diluted weighted average common shares	28,456	28,103	28,454	28,110
Anti-dilutive shares	59	132	37	117