Mobärg was in fourth place for most of the final, but in the last meters he passed Swede Oliver Davies of Great Britain and was awarded third place after reviewing the finish photo.
Frenchman Youri Duplessis-Kergomard won ahead of Canadian Jared Schmidt.
David Mobärg also had a podium finish earlier this season - third place in Arosa, Switzerland.
Older brother Erik Mobärg made it to the quarterfinals.
