OSLO, NORWAY (20 April 2021) - The 2021 Annual General Meeting of TGS-NOPEC Geophysical Company ASA ("TGS" or the "Company") will be held on 11 May 2021 at the offices of Schjødt law firm at Ruseløkkveien 16, in Oslo at 17:00 CET.

Registration of attendees will begin at 16:30 CET.

Due to the extraordinary situation caused by the COVID-19 pandemic, and in light of the travel and meeting recommendations and restrictions currently in place, the Company has found it necessary to urge shareholders to either vote electronically in advance or submit proxy forms prior to the meeting and to not attend the meeting in person.

The notice for the annual general meeting is attached hereto (English and Norwegian), together with relevant appendices. The notice will be sent to all registered shareholders per 20 April 2021.

To register your attendance, send proxy or to cast your vote electronically in advance through VPS Investor Services, please use the electronic link here and available on tgs.com. The pin code and reference number, which are sent out with the notice, will be needed. Kindly note that shareholders that have received the notice electronically will not receive and do not need a pin code or reference number, but must submit their notice of attendance, proxy or advance votes through their online investor account services (investortjenester).

Online registration will open on 20 April 2021 at 14:00 CET.

About TGS
TGS provides scientific data and intelligence to companies active in the energy sector. In addition to a global, extensive and diverse energy data library, TGS offers specialized services such as advanced processing and analytics alongside cloud-based data applications and solutions.

Forward Looking Statement
All statements in this press release other than statements of historical fact are forward-looking statements, which are subject to a number of risks, uncertainties and assumptions that are difficult to predict, and are based upon assumptions as to future events that may not prove accurate. These factors include TGS' reliance on a cyclical industry and principal customers, TGS' ability to continue to expand markets for licensing of data, and TGS' ability to acquire and process data product at costs commensurate with profitability, as well as volatile market conditions, which have been exacerbated by the COVID-19 pandemic and the severe drop in oil prices. Actual results may differ materially from those expected or projected in the forward-looking statements. TGS undertakes no responsibility or obligation to update or alter forward-looking statements for any reason.

For more information, contact:

Fredrik Amundsen
CFO
investor@tgs.com