SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) : August 15, 2003 SPARTECH CORPORATION (Exact name of registrant as specified in its charter) DELAWARE (State or other jurisdiction of incorporation) 1-5911 43-0761773 (Commission File Number) (IRS Employer Identification No.) 120 South Central Avenue, Suite 1700, Clayton, Missouri 63105 (Address of principal executive offices) (Zip Code) (314) 721-4242 (Registrant's Telephone Number, Including Area Code) SPARTECH CORPORATION FORM 8-K Item 9. Regulation FD Disclosure The registrant's press release dated August 15, 2003 regarding its Lean Process Initiative and estimate of resulting annual savings is furnished with this Current Report on Form 8-K as Exhibit 99.1. Item 12. Results of Operations and Financial Condition The registrant's press release dated August 15, 2003 providing guidance for fiscal 2003 third quarter financial results and announcement of a conference call/webcast to discuss Spartech Corporation's fiscal 2003 third quarter earnings is furnished with this Current Report on Form 8-K as Exhibit 99.1. 2 SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. SPARTECH CORPORATION Date August 15, 2003 By /s/ Randy C. Martin Randy C. Martin Executive Vice President and Chief Financial Officer 3 EXHIBIT INDEX Exhibit Number Description 99.1 Press release of Spartech Corporation dated August 15, 2003. 4