0001193125-08-162399 10-Q 10 20080630 20080731 20080731 SEI INVESTMENTS CO 0000350894 6211 231707341 PA 1231 10-Q 34 000-10200 08981313 1 FREEDOM VALLEY DRIVE OAKS PA 19456-1100 6106761000 1 FREEDOM VALLEY DRIVE OAKS PA 19456-1100 SEI INVESTMENT CO 20040806 SEI CORP 19920703 10-Q 1 d10q.htm SEI INVESTMENTS COMPANY - FORM 10-Q EX-3.2.3 2 dex323.htm AMENDED AND RESTATED BY-LAWS EX-10.5.1 3 dex1051.htm EMPLOYEE STOCK PURCHASE PLAN EX-10.29.8 4 dex10298.htm SLAT PO AMENDMENT NO. 8 EX-10.29.9 5 dex10299.htm SLAT PO AMENDMENT NO. 9 EX-10.29.10 6 dex102910.htm SLAT PO AMENDMENT NO. 10 EX-10.29.11 7 dex102911.htm SLAT PO AMENDMENT NO. 11 EX-31.1 8 dex311.htm SECTION 302 CERTIFICATION OF CHIEF EXECUTIVE OFFICER EX-31.2 9 dex312.htm SECTION 302 CERTIFICATION OF CHIEF FINANCIAL OFFICER EX-32 10 dex32.htm SECTION 906 CERTIFICATIONS OF CEO AND CFO