VALLOUREC AND GEOSTOCK SIGN A PARTNERSHIP AGREEMENT TO ACCELERATE LARGE-SCALE STORAGE SOLUTIONS FOR THE ENERGY TRANSITION

VALLOUREC AND GEOSTOCK SIGN A PARTNERSHIP AGREEMENT TO ACCELERATE LARGE-SCALE STORAGE SOLUTIONS FOR THE ENERGY TRANSITION 

Meudon, December 18, 2025 – Vallourec, a world leader in premium seamless tubular solutions, and Geostock, a global specialist in underground storage of energy, have signed a Memorandum of Understanding (MoU) to strengthen their collaboration in developing the infrastructure required for the energy transition, particularly for hydrogen and carbon capture, utilization, and storage (CCUS). 

This collaboration focuses especially on hydrogen storage, where the companies have a complementary product and services offering. Together, Vallourec and Geostock can support the full range of storage needs of the green hydrogen value chain. Vallourec’s turnkey Delphy storage system is capable of storing up to 100 tons of hydrogen under maximum safety conditions, while Geostock’s mined lined rock caverns are ideal for larger capacities (500+ tons). 

Complementarities also extend to both companies’ industrial expertise. For example, Geostock’s deep expertise in subsurface development could be leveraged to support customers in the installation and associated civil engineering for Vallourec’s Delphy solution. 

The agreement also covers cooperation on well architecture and tubular solutions for hydrogen and CCUS applications. Vallourec and Geostock will share their expertise, R&D findings and technical solutions to design wells suited to the demanding conditions of subsurface hydrogen storage and CO₂ injection. Vallourec’s cutting-edge, extensively tested tubular solutions will support Geostock and its customers in deploying safe and high-performance underground storage infrastructures.

This collaboration is part of Vallourec’s broader strategy to partner with key experts and leading players in the New Energies sector. With this network of partners, Vallourec is capable of addressing the industrial, environmental and economic challenges of the energy transition.

Philippe Guillemot, Group Chairman and CEO of Vallourec, commented: “This partnership marks an important step in strengthening our collaboration with a leading expert in underground storage. By joining forces with Geostock, we are accelerating the development of the infrastructure essential to build a performing low-carbon energy value chain in hydrogen storage and CCUS.”

Pascal Baylocq, CEO of Geostock said: “This partnership with a global leader in premium seamless tubes enables Geostock to broaden its range of solutions for underground storage of hydrogen in hard rock. The agreement between our companies also aligns with Geostock’s goal of staying at the forefront of knowledge. Vallourec’s expertise and research capabilities in metallic materials will be leveraged by Geostock across various underground storage techniques, in salt caverns, hard rocks, and porous media.” 

About Vallourec

Vallourec is a world leader in premium tubular solutions for the energy markets and for demanding industrial applications such as oil & gas wells in harsh environments, new generation power plants, challenging architectural projects, and high-performance mechanical equipment. Vallourec’s pioneering spirit and cutting-edge R&D open new technological frontiers. With close to 13,000 dedicated and passionate employees in more than 20 countries, Vallourec works hand- in-hand with its customers to offer more than just tubes: Vallourec delivers innovative, safe, competitive and smart tubular solutions, to make every project possible.
Listed on Euronext in Paris (ISIN code: FR0013506730, Ticker VK), Vallourec is part of the CAC Mid 60, SBF 120 and Next 150 indices and is eligible for Deferred Settlement Service.
In the United States, Vallourec has established a sponsored Level 1 American Depositary Receipt (ADR) program (ISIN code: US92023R4074, Ticker: VLOWY). Parity between ADR and a Vallourec ordinary share has been set at 5:1.


About Geostock


Geostock is a world leader in energy and CO2 underground storage, including consulting, engineering, site construction management and operation of storage plants. Geostock offers various services for different underground storage techniques: salt caverns, mined caverns, and porous media. Geostock's experience covers a variety of geologies. Geostock was created more than 60 years ago. Geostock is present on all continents and has clients in more than 50 countries worldwide.

Geostock is developing a concept of lined mined rock cavern storage suitable for hydrogen storage in hard rock.

For further information, please contact:

Investor relations:

Connor Lynagh
Tel: +1 (713) 409-7842
connor.lynagh@vallourec.com

Individual shareholders:

Toll Free number (From France): 0 805 65 10 10
actionnaires@vallourec.com

Press relations: Taddeo

Romain Grière
Tel: +33 (0) 7 86 53 17 29
Tel: + 1 718 421 8374
romain.griere@taddeo.fr

Nicolas Escoulan
Tel: +33 (0)6 42 19 14 74
nicolas.escoulan@taddeo.fr

Communication manager – Geostock:

Olivier Dannenmuller
Tel: +33 (0) 6 07 80 28 58
Olivier.dannenmuller@geostock.fr

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