<SEC-DOCUMENT>0000866609-20-000036-index.html : 20200513 <SEC-HEADER>0000866609-20-000036.hdr.sgml : 20200513 <ACCEPTANCE-DATETIME>20200513080053 ACCESSION NUMBER: 0000866609-20-000036 CONFORMED SUBMISSION TYPE: DEFA14A PUBLIC DOCUMENT COUNT: 1 FILED AS OF DATE: 20200513 DATE AS OF CHANGE: 20200513 EFFECTIVENESS DATE: 20200513 FILER: COMPANY DATA: COMPANY CONFORMED NAME: ION GEOPHYSICAL CORP CENTRAL INDEX KEY: 0000866609 STANDARD INDUSTRIAL CLASSIFICATION: OIL AND GAS FIELD EXPLORATION SERVICES [1382] IRS NUMBER: 222286646 STATE OF INCORPORATION: DE FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: DEFA14A SEC ACT: 1934 Act SEC FILE NUMBER: 001-12691 FILM NUMBER: 20871101 BUSINESS ADDRESS: STREET 1: 2105 CITYWEST BLVD STREET 2: SUITE 100 CITY: HOUSTON STATE: TX ZIP: 770422855 BUSINESS PHONE: 2819333339 MAIL ADDRESS: STREET 1: 2105 CITYWEST BLVD STREET 2: SUITE 100 CITY: HOUSTON STATE: TX ZIP: 770422855 FORMER COMPANY: FORMER CONFORMED NAME: INPUT OUTPUT INC DATE OF NAME CHANGE: 19930328 </SEC-HEADER> <DOCUMENT> <TYPE>DEFA14A <SEQUENCE>1 <FILENAME>a2020annualmeetingaddition.htm <DESCRIPTION>DEFA14A ADDITIONAL MATERIALS <TEXT> Document 1 - file: a2020annualmeetingaddition.htm
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