Geostock
Oil and GasÎle-de-france, France201-500 Employees
Geostock is an international firm based in Rueil-Malmaison, Île-de-France, specializing in underground energy storage. With around five decades of experience, it delivers services across the full lifecycle of storage facilities—from concept and design to construction management, operation and maintenance—regardless of storage method or product. Its multi-skilled staff work with salt caverns, mined caverns and porous reservoirs, and the company operates globally as a subsidiary of Vinci Construction Grands Projets. The company serves clients in the oil and gas sector by addressing technical and operational challenges throughout a storage project's life. A recent development is a January 2026 partnership with Vallourec to develop infrastructure solutions for the energy transition, underscoring its role in the evolving energy landscape.