================================================================================ FORM 10-K/A-1 SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 -------------------- [X] ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 [FEE REQUIRED] FOR THE FISCAL YEAR ENDED MAY 31, 1999 OR [ ]TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 [NO FEE REQUIRED] FOR THE TRANSITION PERIOD FROM ______ TO ______ COMMISSION FILE NUMBER 1-13402 INPUT/OUTPUT, INC. (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER) DELAWARE 22-2286646 (STATE OR OTHER JURISDICTION OF (I.R.S. EMPLOYER INCORPORATION OR ORGANIZATION) IDENTIFICATION NO.) 11104 WEST AIRPORT BLVD., STAFFORD, TEXAS 77477 (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES) (ZIP CODE) REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: (281) 933-3339 SECURITIES REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT: COMMON STOCK, $0.01 PAR VALUE NEW YORK STOCK EXCHANGE PREFERRED STOCK PURCHASE RIGHTS NEW YORK STOCK EXCHANGE (TITLE OF CLASS) (NAME OF EACH EXCHANGE ON WHICH REGISTERED) SECURITIES REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT: NONE Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes: [X] No: [ ] Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. [ ] Aggregate market value of the voting and non-voting common equity held by non-affiliates of the registrant at June 30, 1999 (for purposes of the below-stated amount only, all directors, officers and 5% or more stockholders are presumed to be affiliates): $287,235,000 Indicate the number of shares outstanding of the registrant's classes of Common Stock, as of the latest practicable date. TITLE OF EACH CLASS NUMBER OF SHARES OUTSTANDING OF COMMON STOCK AT JUNE 30, 1999 --------------- ---------------- COMMON STOCK, $0.01 PAR VALUE 50,663,858 DOCUMENTS INCORPORATED BY REFERENCE Portions of the definitive Proxy Statement for the Registrant's 1999 Annual Meeting of Stockholders are incorporated by reference into Part III hereof. ================================================================================ PART IV ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K: (3) Exhibits: 23.1 - Consent of KPMG LLP 99.1 - Information, Financial Statements and Exhibits required by Form 11-K for the Input/Output, Inc. Employee Stock Purchase Plan SIGNATURES The undersigned registrant hereby amends the following items, financial statements and exhibits of its Annual Report for its fiscal year ended May 31, 1999 on Form 10-K as set forth in the pages attached hereto: To file as Exhibit 99.1 the Information, Financial Statements and Exhibits required by Form 11-K for the Input/Output, Inc. Employee Stock Purchase Plan. Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this Form 10-K/A-1 report to be signed on its behalf by the undersigned, thereunto duly authorized in the city of Stafford, State of Texas, on October 28, 1999. Input/Output, Inc. /s/ Sam K. Smith --------------------------------- Director and Chief Executive Officer 2