Gaztransport et Technigaz SA is a French engineering company specializing in cryogenic membrane containment systems for the maritime transportation and storage of liquefied natural gas (LNG). Formed in 1994 from the merger of Gaztransport and Technigaz, it holds a leading global position, designing innovative technologies like NO96 and Mark III that maintain LNG at -163°C, enabling efficient shipping and reducing volume by 600 times compared to gaseous state. The company licenses these systems to shipyards, primarily in South Korea and China, for LNG carriers, floating storage units, multigas tankers, and offshore applications. Beyond core royalties from vessel construction, Gaztransport et Technigaz SA provides engineering consultancy, training, maintenance support, digital solutions for smart shipping, and electrolysers for green hydrogen production via its Elogen subsidiary. It also develops LNG propulsion for merchant vessels and small-scale storage solutions, serving energy firms, terminal operators, and classification societies. Headquartered in Saint-Rémy-lès-Chevreuse with around 888 employees, the firm drives advancements in sustainable marine energy infrastructure and emerging markets like hydrogen and biogas.