Exhibit 11

Simpson Manufacturing Co., Inc. and Subsidiaries
Computation of Earnings Per Common Share

(Unaudited)

Basic Earnings per Share

		Three Months Ended September 30,						Nine Months Ended September 30,
		2003			2002			2003			2002
Weighted average number of common shares outstanding		24,677,648			24,500,445			24,621,404			24,445,550
Net income		$	18,557,490		$	16,715,142		$	47,263,999		$	41,336,683
Basic net income per share		$	0.75		$	0.68		$	1.92		$	1.69

Diluted Earnings per Share

		Three Months Ended September 30,						Nine Months Ended September 30,
		2003			2002			2003			2002
Weighted average number of common shares outstanding		24,677,648			24,500,445			24,621,404			24,445,550
Shares issuable pursuant to employee stock option plans, less shares assumed repurchased at the average fair value during the period		439,454			307,020			386,988			332,296
Shares issuable pursuant to the independent director stock option plan, less shares assumed repurchased at the average fair value during the period		6,485			3,970			5,595			4,295
Number of shares for computation of diluted net income per share		25,123,587			24,811,435			25,013,987			24,782,141
Net income		$	18,557,490		$	16,715,142		$	47,263,999		$	41,336,683
Diluted net income per share		$	0.74		$	0.67		$	1.89		$	1.67

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