He had held a series of executive positions at CBS from July 1995 to September 2018. He has been on the Board of Directors at ZeniMax Media since 1999. Later, he was co-President and co-Chief Operating Officer (COO) of the original Viacom, Inc. , the legal predecessor to CBS Corporation, from 2004 until the company split in December 2005. He became Chairman of CBS in February 2016. On September 9, 2018, Les Moonves stepped down as Chairman of CBS after multiple sexual harassment claims.