A flaw in the ice-class calculation methodology used under FuelEU Maritime has left compliant shipping operators facing potential penalties running into tens of millions of euros – through no fault of their own. The error, which was embedded in the European Maritime Safety Agency’s (EMSA) Thetis compliance system and widely adopted by third-party verifiers, affected how energy is allocated to voyages with partial EU regulatory exposure. It went undetected through the individual vessel verification deadline of March 31 2026, meaning numerous ice-class vessels received approved compliance balances based on incorrect data before the pooling period even began. Risto-Juhani Kariranta, CEO of Ahti Climate – which manages hundreds of vessels for owners including Van Weelde Group, Bore, Spliethoff, Stenersen, BBC Chartering and Neste, and administers more than €100m of FuelEU Maritime emissions exposure – says the consequences could be severe. “Individual cases may involve exposures in the order of several million euros,” he warned. EMSA corrected the formula on April 16, updating compliance balances in Thetis. DNV, one of the largest verifiers, began notifying affected customers on April 21, recommending they delay pooling decisions until the corrected figures were reflected. But for pools already finalised and verified before the correction, the damage may be done. Those pools are now locked in the system with no mechanism to reopen or revise them. Kariranta illustrated the scale of the problem with a concrete example. One pool Ahti organised – already approved using the incorrect values – involved a transfer of approximately 16,000 tCO₂e with a market value of just over €3m. Under the corrected methodology, that pool could be rendered non-compliant, with penalty consequences potentially exceeding €10m. “This creates a situation where operators may face significant financial consequences due to an error that was outside their control and could not reasonably have been anticipated,” he said. With the pool finalisation deadline falling on April 30, Kariranta is calling for urgent intervention. Ahti has requested guidance from DG MOVE and EMSA on whether affected pools can be reopened and adjusted to avoid unintended non-compliance. googletag.cmd.push(function() { googletag.display('div-gpt-ad-1_95_0_1_2'); });