As filed with the Securities and Exchange Commission on December 18, 2006 Registration Statement No. 333-38246 SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-3 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 ------------------------ SPARTECH CORPORATION (Exact name of registrant as specified in its charter) DELAWARE 43-0761773 (State or other jurisdiction of (IRS Employer Identification No.) incorporation or organization) 120 SOUTH CENTRAL AVENUE, SUITE 1700 CLAYTON, MISSOURI 63105 (314) 721-4242 (Address, including zip code, and telephone number, including area code, of registrant's principal executive offices) ------------------------ JEFFREY D. FISHER SENIOR VICE PRESIDENT AND GENERAL COUNSEL SPARTECH CORPORATION 120 SOUTH CENTRAL AVENUE, SUITE 1700 CLAYTON, MISSOURI 63105 (314) 721-4242 (Name, address, including zip code, and telephone number, including area code, of agent for service) EXPLANATORY NOTE In accordance with an Undertaking made as provided in Item 17(a)(3) of the registration statement, this Post-Effective Amendment No. 1 is being filed with respect to a currently effective Registration Statement on Form S-3 as filed on May 31, 2000, Registration No. 333-38246, solely to deregister the 1,636,700 shares of common stock, par value $0.75 per share, of Spartech Corporation which were registered and reserved for issuance under the Registration Statement, but which have not been issued and are currently not outstanding. The 1,636,700 shares of common stock subject to the registration statement are the shares that were formerly subject to issuance upon the conversion of an aggregate of 1,000,000 6.50% Convertible Preferred Securities (liquidation preference $50 per Convertible Preferred Security) of Spartech Capital Trust, a Delaware business trust. The Convertible Preferred Securities were issued in March, 1999. The registered shares were registered for secondary sale by the holders of the Convertible Preferred Securities following conversion; however, the convertible securities were never converted and were redeemed and cancelled by the registrant; and thus the registered shares cannot be issued or resold. Accordingly, the registrant hereby deregisters all 1,636,700 shares of common stock subject to the registration statement. SIGNATURES Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all the requirements for filing on Form S-8 and has duly caused this post-effective amendment to the registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Clayton, State of Missouri, on December 15, 2006. SPARTECH CORPORATION By: /s/ George A. Abd ------------------------------------- George A. Abd President and Chief Executive Officer Pursuant to the requirements of the Securities Act of 1933, this post-effective amendment to the registration statement has been signed by the following persons in the capacities and on the dates indicated. Signature Title Date Signed - --------- ----- ----------- /s/ George A. Abd President and Chief Executive Officer December 15, 2006 - ------------------------------- and Director (Principal Executive Officer) George A. Abd /s/ Randy C. Martin Executive Vice President and Chief Financial December 15, 2006 - ------------------------------- Officer (Principal Financial and Accounting Officer) Randy C. Martin /s/ Ralph B. Andy Director December 15, 2006 - ------------------------------- Ralph B. Andy /s/ Lloyd E. Campbell Director December 15, 2006 - ------------------------------- Lloyd E. Campbell /s/ Edward J. Dineen Director December 15, 2006 - ------------------------------- Edward J. Dineen /s/ Victoria M. Holt Director December 15, 2006 - ------------------------------- Victoria M. Holt /s/ Walter J. Klein Director December 15, 2006 - ------------------------------- Walter J. Klein /s/ Pamela F. Lenehan Director December 15, 2006 - ------------------------------- Pamela F. Lenehan /s/ Jackson W. Robinson Director December 15, 2006 - ------------------------------- Jackson W. Robinson /s/ Craig A. Wolfanger Director December 15, 2006 - ------------------------------- Craig A. Wolfanger