Pangaea, a 33-metre-long aluminum ketch, was immobilized in La Ciotat, east of Marseille, after boat designer Olivier Petit launched legal action against Horn, the French regional newspaper La Provence reported on Thursday.
Petit, who claims the boat is an exact copy of his design, is claiming 300,000 euros (375,00 francs) from Horn for the plans he drew up.
According to La Provence, Petit alleges that Horn asked him to draw up plans for a boat in 2007 but the two could not reach an agreement on the price.
Horn then commissioned a Brazilian boat builder Thierry Stump to build the two-mast sailboat, which Petit claims uses his design.
Contacted by 20Minutes.ch, the Swiss French-language online news site, Mike Horn’s wife Cathy Horn disputed versions of the facts that have appeared in French media.
“Mike Horn is in the middle of a dispute between two architects,” she said.
“His job is neither to make plans for or to build boats,” she said.
“He’s an explorer who works with young people to save the planet.”
Horn said the dispute was between the naval architects Stump and Petit.
Petit “thinks Mike stole the plans, which is ridiculous,” she said.
There is “no reason to implicate Mike in this dispute”.
Horn, born in South Africa, officially resides in Château d’Oex, a municipality in the Vaud Alps.
But he spends most of his time travelling around the world, using his experiences to motivate sportsmen and young people while campaigning for protection of the environment.
His boat was undergoing repairs in La Ciotat prior to a planned trip to Greenland.