X0306 4 2021-05-11 0 0000866609 ION GEOPHYSICAL CORP IO 0001799422 LAMBERT DALE J 2105 CITYWEST BLVD., SUITE 100 HOUSTON TX 77042 0 1 0 0 EVP, E&P Technology & Services Common Stock 2021-05-11 4 A 0 61500 0.00 A 102316 D Restricted Stock award issued pursuant to the ION Geophysical Corporation Fourth Amended and Restated 2013 Long Term Incentive Plan ("2013 LTIP"). The shares of restricted stock will vest in three equal annual installments beginning on May 11, 2022. /s/ Rebecca F. Sacco, attorney-in-fact 2021-05-13