Vesting of 2015 Long Term Incentive Plan

ASKER, NORWAY (5 August 2018) - In accordance with the measures approved by the Shareholders of TGS at the Annual General Meeting on 6 May 2015, the Board of Directors of TGS NOPEC Geophysical Company ASA granted PSUs (Performance Stock Units) and RSUs (Restricted Stock Units) under the 2015 Long Term Incentive Plan to 91 key employees of the company on 5 August 2015. Each RSU represented the right to receive one share, while each PSU represented the right to receive a maximum of one share depending on performance versus target metrics measured through the period 1 January 2015 to 31 December 2017. The granted PSUs and RSUs were secured by free-standing warrants and vested on the third anniversary of the date of the grant.

The Board of Directors has concluded that none of the 2015 PSUs will be converted into TGS shares as the minimum performance thresholds were not achieved.

On 5 August 2018 the RSUs vested, and 67 RSU holders subscribed for a total of 98,800 TGS shares at par value NOK 0.25.

The following primary insiders have subscribed for TGS shares related to the vesting of the RSUs:

Fredrik Amundsen has subscribed for 2,500 shares

William Ashby has subscribed for 1,800 shares

Victor Marchon has subscribed for 2,500 shares

Amund Soia has subscribed for 1,480 shares

Attached is the list of primary insiders subscribing for TGS shares in relation to the vesting of the RSUs.

Also attached is the list of primary insiders with free-standing warrants related to PSUs and RSUs, with the balance of warrants reduced following vesting of the 2015 Long Term Incentive Plan.

Company Summary

TGS-NOPEC Geophysical Company (TGS) provides multi-client geoscience data to oil and gas Exploration and Production companies worldwide.  In addition to extensive global geophysical and geological data libraries that include multi-client seismic data, magnetic and gravity data, digital well logs, production data and directional surveys, TGS also offers advanced processing and imaging services, interpretation products, and data integration solutions.

For more information visit TGS online at www.tgs.com.

Forward-looking statements and contact information

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 principle customers, TGS' ability to continue to expand markets for licensing of data, and TGS' ability to acquire and process data products at costs commensurate with profitability. 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.

TGS-NOPEC Geophysical Company ASA is listed on the Oslo Stock Exchange (OSLO:TGS).

TGS sponsored American Depositary Shares trade on the U.S. over-the-counter market under the symbol "TGSGY".

For additional information about this press release please contact:

Sven Børre Larsen
Chief Financial Officer
Tel: +47 90 94 36 73
Email: sven.larsen@tgs.com

Will Ashby
SVP Investor Relations, HR & Communication
Tel: +1 713 860 2184 
Email: will.ashby@tgs.com