X0304 4 2011-12-05 0000804212 AIRGAS INC ARG 0001237784 MCLAUGHLIN ROBERT M C/O AIRGAS, INC. 259 N. RADNOR-CHESTER ROAD, SUITE 100 RADNOR PA 19087 0 1 0 0 Senior VP and CFO Common Stock 2011-12-05 4 M 0 10300 19.22 A 22406 D Common Stock 2011-12-05 4 M 0 5000 21.15 A 27406 D Common Stock 2011-12-05 4 S 0 12000 77.02 D 15406 D Common Stock 379 I By 401(k) Plan Stock Option (Right to Buy) 19.22 2011-12-05 4 M 0 10300 D 2013-05-12 Common Stock 10300 0 D Stock Option (Right to Buy) 21.15 2011-12-05 4 M 0 5000 D 2014-05-25 Common Stock 5000 5000 D Includes 8,106 shares of Airgas, Inc. common stock acquired pursuant to Airgas, Inc.'s Employee Stock Purchase Plan ("ESPP") as of 12/5/2011, the date of the latest available statement of the reporting person's ESPP holdings. Since 6/7/2011, the date of the statement relied upon for the amount reported on the reporting person's 6/9/2011 Form 4, a total of 168 ESPP shares have been acquired in transactions exempt from Section 16(b). This price represents the average selling price (within a range of $76.91-$77.05) of the shares of common stock of Airgas, Inc. sold by the reporting person, as provided by the reporting person's broker. The information presented is as of 12/5/2011, the date of the latest available statement of the reporting person's holdings of Airgas, Inc. common stock in his 401(k) plan. Since 6/7/2011, the date of the statement relied upon for the amount reported on the reporting person's 6/9/2011 Form 4, a total of 35 shares have been acquired in transactions exempt from Section 16(b). These options became exercisable in 25% equal increments on each of 5/12/2004, 5/12/2005, 5/12/2006 and 5/12/2007. Not Applicable. These options became exercisable in 25% equal increments on each of 5/25/2005, 5/25/2006, 5/25/2007 and 5/25/2008. Robert H. Young, Jr., Attorney-In-Fact for Robert M. McLaughlin 2011-12-07