X0303 4 2010-02-26 0 0000072020 NICOR INC GAS 0001349585 OCONNOR GERALD P NICOR INC. 1844 FERRY ROAD NAPERVILLE IL 60563 0 1 0 0 Senior Vice President Common Stock 2010-02-26 4 S 0 2085 41.61 D 2158.609 D Common Stock 2010-02-26 4 S 0 100 41.62 D 2058.609 D Common Stock 2010-02-26 4 S 0 300 41.60 D 1758.609 D Common Stock 2010-02-26 4 S 0 15 41.70 D 1743.609 D Prior to these sales transactions the amount of securities beneficially owned was 4243.609 which included 2343 shares of common stock acquired under the Nicor Inc. Employee Stock Purchase Plan in June, September and December of 2006 and March, June, September and December 2007 through 2009 and 230.609 shares under the Dividend Reinvestment Plan in August and November 2006 and February, May, August and November 2007 through 2009 and in February 2010. Antoinette M. Lambert - Attorney-in-Fact 2010-03-01