France has given Mantle8 exclusive rights for five years to explore for natural hydrogen across 739 square kilometers in the Pyrenees, handing the Grenoble-based start-up a key regulatory win while stopping short of allowing it to drill.

The permit covers the Comminges region in southern France and comes after Mantle8 recently raised €31 million in Series A financing. Geophysical surveys have already begun across the area, giving the company its first extended window to test whether the site can support a commercial hydrogen project.

That matters now because the permit is not a blanket green light. Mantle8 can carry out exploration activities, but it still needs separate approval before it can begin drilling. For a company trying to turn early geological signals into a future energy asset, the distinction decides how fast the project can move and how far the French state is prepared to let it go.

Mantle8 says the case for the permit was built on work it carried out at the location last year, when it used proprietary subsurface modelling and exploration technologies. The company said the data pointed to an active hydrogen-generating source that replenishes sealed reservoirs, a finding it said supported the application now approved by the French government.

Natural hydrogen has drawn growing interest because it can be found underground without the emissions footprint of making the gas from fossil fuels. In this case, though, the practical hurdle remains the same as it was before the permit was granted: Mantle8 must first prove enough with surveys and data to persuade regulators that drilling should follow. The company has the land access. It does not yet have the right to break ground.

That leaves the next step in regulators’ hands as much as in Mantle8’s. The surveys now under way can sharpen the case for drilling, but they cannot replace the separate authorization the company will need before any well is started. For now, the award gives Mantle8 time, exclusivity and room to search — not the final permission that would turn the Pyrenees project from exploration into extraction.