GTT: Catherine Ronge Replaces Philippe Berterottière as Board Chair

An Independent Director Since 2021 Leading the Board

The board of directors of GTT, meeting on October 23, 2026, decided to appoint Catherine Ronge as chair of the board of directors, replacing Philippe Berterottière. The group specified that this appointment is part of the succession plan established by the board.

Catherine Ronge has served on the board as an independent director since 2021. She previously chaired the nominations and remuneration committee, a position she has held since 2023, and has been a member of the strategy and corporate social responsibility committee since 2021.

A former student of École Normale Supérieure Paris-Saclay and a doctorate holder in quantum physics, she began her career at the CEA in 1984 as a research engineer, before holding several positions at Air Liquide (1988 to 1999), then at Suez (1999 to 2006), where she notably served as Chief Executive Officer of Ondeo Industrial Solutions. She subsequently founded and chaired the consulting firm Weave Air (2006 to 2020). She has also been Chief Executive Officer of the Le Garrec & Cie group since June 2026. She is also a director of Colas since 2014 and a censor of Paprec.

In his statement, Philippe Berterottière indicated that "after seventeen years at the head of GTT", the time had come for him to step down, considering that the transition with François Michel had been successfully completed.

Eight Directors and Reconstituted Committees

Following these changes, GTT's board of directors will comprise eight members, of which seven are independent directors (88%), and 50% women. A recruitment process for an additional independent director is underway.

The board's committees are also evolving. Sandra Lagumina succeeds Catherine Ronge as chair of the nominations and remuneration committee and leaves the audit and risks committee, now chaired by Pascal Macioce. Luc Gillet joins the nominations and remuneration committee, replacing Pierre Guiollot.

François Michel for his part recalled the new organization of the group around two divisions, Energy and Marine, and indicated that he has worked with Catherine Ronge within the board and the nominations and remuneration committee in recent months.