Dec 11 (Reuters) - The Icahn Group has reduced its holdings in FirstEnergy below 1.5%, which forced billionaire investor Carl Icahn's firm to give up a board seat under an agreement between the companies, according to a regulatory filing.

Andrew Teno, a member of the board, has tendered his resignation, the filing added. (Reporting by Jaiveer Singh Shekhawat in Bengaluru; Editing by Krishna Chandra Eluri)