X0304 4/A 2010-12-03 2010-12-07 false 0000090185 SIGMA ALDRICH CORP SIAL 0001472382 MILLER GEORGE LLOYD 3050 SPRUCE STREET ST. LOUIS MO 63103 false true false false Sr. VP, General Counsel & Sec. Common Stock Units 386.174 I By 401(K) Plan Common Stock 2010-12-03 4 P false 1100 65.29 A 3522 D The Common Stock Units represent interests in the SIAL stock fund in the SIAL 401(k) plan. The information in this report is based on a plan statement dated as of December 3, 2010. The amount of Common Stock Units was inadvertently ommitted from the original report. The amount of securities in column 5 is 357 shares lower than the same amount on the original report due to the withholding of SIAL Common Stock to satisfy tax withholding obligations on the vesting of Restricted Stock Units, which was not timely reported. See the reporting person's Form 4 filed March 8, 2012 with a transaction date of September 30, 2012 Due to administrative oversight, the transaction code on the original report was incorrectly reflected as an "A." Kim Reno, By Power of Attorney 2012-03-09