Company Announcements

NOT FOR RELEASE, PUBLICATION OR DISTRIBUTION, IN WHOLE OR IN PART, DIRECTLY OR INDIRECTLY, INTO OR WITHIN AUSTRALIA, CANADA, HONG KONG, JAPAN, SOUTH AFRICA, THE UNITED STATES OR ANY OTHER JURISDICTION IN WHICH THE DISTRIBUTION OR RELEASE WOULD BE UNLAWFUL

Oslo, Norway (10 November 2022) - Reference is made to the stock exchange announcement on 11 October 2022 regarding the completion of the recommended voluntary exchange offer by TGS ASA ("TGS" or the "Offeror", OSE: TGS), where it was informed that TGS held 204,854,978 shares in Magseis Fairfield ASA ("Magseis Fairfield", OSE: MSEIS), representing approximately 75.40% of the issued and outstanding shares in Magseis Fairfield), thereby triggered an obligation to make a mandatory offer for all the remaining shares in Magseis Fairfield pursuant to Chapter 6 of the Norwegian Securities Trading Act. In addition, TGS holds warrants to subscribe for 18,250,000 new shares of Magseis Fairfield. TGS is today launching a mandatory offer to acquire all the shares in Magseis Fairfield that are not already owned by TGS (the "Mandatory Offer" or the "Offer").

The terms and conditions of the Mandatory Offer are set out in a mandatory offer document prepared by TGS dated 10 November 2022 (the "Mandatory Offer Document"), which has been approved by the Oslo Stock Exchange in its capacity as take-over supervisory authority.

The main terms and conditions for the Mandatory Offer:

• Consideration and Offer Price: NOK 8.08 in cash per share in Magseis Fairfield
• Acceptance Period: 11 November 2022 to 21 December 2022 at 16:30 (CET)
• Settlement: Will be made promptly after expiration of the Mandatory Offer, and in any event within 14 days after expiry of the Acceptance Period.

The Mandatory Offer may only be accepted on the basis of the Mandatory Offer Document, which will be distributed to the shareholders in Magseis Fairfield as registered in the Norwegian Central Securities Depository (the "VPS", also known as Euronext Securities Oslo) as of the date of the Mandatory Offer Document, except for shareholders in jurisdictions where it may not be lawfully distributed.

The Mandatory Offer Document will be, subject to regulatory restrictions in certain jurisdictions, also available at www.abgsc.no, from 11 November 2022, the date for commencement of the acceptance period, and may be obtained free of charge during ordinary business hours at the offices of the receiving agent, ABG Sundal Collier ASA, Ruseløkkveien 26, 0251 Oslo, Norway.

Advisors:

ABG Sundal Collier ASA acts as financial advisor to TGS and receiving agent for the Mandatory Offer. Advokatfirmaet Schjødt AS acts as legal advisor to TGS. Arctic Securities AS acts as financial advisor and Advokatfirmaet Thommessen AS acts as legal advisor to Magseis Fairfield.

Contacts:

TGS: Sven Børre Larsen, CFO
Tel: +47 909 43 673
Email: investor@tgs.com

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.

Important notice:

This information is subject to the disclosure requirements pursuant to section 5-12 of the Norwegian Securities Trading Act.

It may be unlawful to distribute this announcement in certain jurisdictions. This announcement is not for distribution in Australia, Canada, the Hong Kong special administrative region of the People's Republic of China, Japan, South Africa, the United States or to any other jurisdiction where such distribution would be unlawful. The information in this announcement does not constitute an offer of securities for sale in such jurisdictions. Persons into whose possession this release comes should inform themselves about and observe any such restrictions. Any failure to comply with these restrictions may constitute a violation of the securities laws of any such jurisdiction. This announcement does not constitute an offer for sale of, or a solicitation of an offer to purchase or subscribe for, any securities in the United States.

Neither TGS, Magseis Fairfield nor any of their advisors and/or any of their affiliates or any of their respective directors, officers, employees, advisers, agents or any other person(s) accept any responsibility or liability whatsoever for, or make any representation or warranty, express or implied, as to the accuracy, completeness or fairness of the information or opinions in this announcement (or whether any information has been omitted from this announcement) or any other information relating the Mandatory Offer, TGS or Magseis Fairfield.

Mandatory Offer Restrictions

The distribution of the Mandatory Offer Document and the making of the Mandatory Offer may in certain jurisdictions ("Restricted Jurisdictions") be restricted by law. Therefore, persons obtaining the Mandatory Offer Document or into whose possession the Mandatory Offer Document otherwise comes, are required to, and should inform themselves of and observe, all such restrictions. The Offeror and the Receiving Agent do not accept or assume any responsibility or liability for any violation by any person whomsoever of any such restriction.

The Mandatory Offer Document is not directed to persons whose participation in the Mandatory Offer requires that further offer documents are issued or that registration or other measures are taken, other than those required under Norwegian law, provided, however, that the Mandatory Offer is made to Magseis Fairfield shareholders resident in the United States, see further below. No document or materials relating to the Mandatory Offer may be distributed in or into any jurisdiction where such distribution or offering requires any of the aforementioned measures to be taken or would be in conflict with any law or regulation of such a jurisdiction. In the event of such distribution or offering still being made, an Acceptance Form sent from such a country may be disregarded.

The Mandatory Offer Document does not represent an offer to acquire or obtain securities other than Magseis Fairfield shares. The Mandatory Offer is not open to any Magseis Fairfield shareholder in any jurisdiction in which it is unlawful for any person to receive or accept the Mandatory Offer. No action has been taken to permit the distribution of the Mandatory Offer in any jurisdiction where action would be required for such purposes (except Norway).

The Mandatory Offer is not being made and will not be made, directly or indirectly, in or into the Restricted Jurisdictions. The Mandatory Offer Document, and any and all materials related thereto, should not be sent or otherwise distributed in or into the Restricted Jurisdictions, and the Mandatory Offer cannot be accepted by any such use, means or instrumentality, in or from within Restricted Jurisdictions. Accordingly, copies of the Mandatory Offer Document and any related materials are not being, and must not be, sent or otherwise distributed in or into or from any Restricted Jurisdiction or, in their capacities as such, to custodians, trustees or nominees holding shares in Magseis Fairfield for persons in any Restricted Jurisdictions, and persons receiving any such documents (including custodians, nominees and trustees) must not distribute or send them in, into or from any Restricted Jurisdiction. Any purported acceptance of the Mandatory Offer resulting directly or indirectly from a violation of these restrictions will be invalid.

Notice to U.S. Investors

The Mandatory Offer is being made for securities of a Norwegian company, and Magseis Fairfield Shareholders in the United States should be aware that the Mandatory Offer Document and any other documents relating to the Mandatory Offer have been or will be prepared in accordance with Norwegian law, format and style, all of which differ from those in the United States. All financial information that is included in the Mandatory Offer Document, or any other documents relating to the Mandatory Offer, have been or will be prepared in accordance with the International Financial Reporting Standards as adopted by the EU (the "IFRS") and may not be comparable to financial statements of companies in the United States or other companies whose financial statements are prepared in accordance with U.S. generally accepted accounting principles. Neither the U.S. Securities and Exchange Commission ("SEC") nor any U.S. state securities commission has approved or disapproved the Mandatory Offer or passed any comment upon the adequacy or completeness of the Mandatory Offer Document. Any representation to the contrary is a criminal offence in the United States. Nothing in the Mandatory Offer Document shall be deemed an acknowledgement that any SEC filing is required or that an offer requiring registration under the U.S. Securities Act may ever occur in connection with the Mandatory Offer. The Mandatory Offer will be made in the United States pursuant to Section 14(e) of, and Regulation 14E under, the U.S. Securities Exchange Act of 1934, as amended (the “U.S. Exchange Act”), and otherwise in accordance with the requirements of Norwegian law. Accordingly, the Mandatory Offer will be subject to disclosure and other procedural requirements, including with respect to withdrawal rights that are different from those applicable under United States domestic tender offer procedures and law, as described elsewhere in the Mandatory Offer Document.