Grenoble, France – Mantle8, the deep-tech geoscience company pioneering natural hydrogen exploration, is strengthening its leadership team as it moves into its next phase of growth, appointing Sylvain Marcant as Chief Commercial Officer to support international expansion, strategic partnerships and commercial scale-up.

The appointment comes as Mantle8 transitions from exploration validation towards broader market engagement, following the successful imaging of complete hydrogen-generating systems using its proprietary HOREX technology. With interest in natural hydrogen accelerating globally, the company is now focused on building the commercial and industrial pathways needed to bring this emerging energy resource to market.

Marcant brings more than 20 years of experience in the upstream oil and gas sector, spanning field operations, technology-led services and senior commercial leadership. He has spent 13 years based in the Middle East, with responsibilities across MENA, Europe and Asia, giving him deep exposure to international energy markets, operating environments and geopolitical contexts.

He most recently served as Eastern Hemisphere Technical and Commercial Director at Varel Energy Solutions, a global provider of drilling and well construction technologies. In that role, he led international expansion, market development, and the structuring of commercial and industrial partnerships across the upstream oil and gas sector, working closely with national oil companies, international oil companies and major service providers.

Earlier in his career, Marcant worked for both an international oil company and leading service companies, combining hands-on experience in field operations, including coring and drilling, with senior responsibilities in business development, sales and commercial strategy. He also brings strong technical expertise in well logging, drill design and drilling operations, aligning closely with Mantle8’s science-first, technology-driven approach.

At Mantle8, Marcant will focus on shaping commercial strategy as the company scales, developing partnerships with energy, industrial and infrastructure players, and supporting the transition from exploration success to market-ready projects.

“Mantle8 has reached a pivotal moment,” said Emmanuel Masini, Founder and CEO of Mantle8. “We have validated our predictive exploration model and demonstrated our ability to image full hydrogen-generating systems. The priority now is scale, partnerships and execution. Sylvain brings deep industry credibility, technical understanding and international experience that will be critical as we move into this next phase.”

Commenting on his appointment, Sylvain Marcant said: “Natural hydrogen represents a major opportunity to deliver a low-cost, low-carbon and sovereign energy resource. Mantle8 has built a unique geoscience and technology platform, and I look forward to working with partners across the energy value chain to help translate this potential into scalable, commercial projects.”

Mantle8 recently produced the world’s first 3D images of an active natural hydrogen system, establishing a repeatable and cost-effective framework for exploration. The company holds multiple exploration permits close to demand centres and is positioning itself to play a role in Europe’s evolving approach to clean molecules, energy sovereignty and long-term industrial competitiveness.
With this leadership reinforcement, Mantle8 is advancing from proof to scale, laying the foundations for the next chapter in natural hydrogen development.