0001193125-06-015238 10-K/A 4 20041231 20060130 20060130 GSI GROUP INC 0001050925 3523 370856587 DE 1231 10-K/A 34 333-43089 06562960 1004 EAST ILLINOIS ST ASSUMPTION IL 62510 2172264421 1004 EAST ILLINOIS ST ASSUMPTION IL 62510 10-K/A 1 d10ka.htm AMENDMENT NO. 2 TO FORM 10-K EX-31.1 2 dex311.htm CERTIFICATION OF CHIEF EXECUTIVE OFFICER EX-31.2 3 dex312.htm CERTIFICATION OF CHIEF FINANCIAL OFFICER EX-32.1 4 dex321.htm SECTION 906 CERTIFICATION