• by Wayne Friedman , February 3, 2016

With the backdrop of Sumner Redstone’s ongoing health concerns, Les Moonves has been named chairman of CBS Corp. Moonves has been president/CEO of the company.

Redstone has resigned as executive chairman; he will be chairman emeritus of CBS. Analysts expect that Redstone will also resign as executive chairman of Viacom. National Amusements, which Redstone controls, is the controlling shareholder of Viacom and CBS.

Moonves will also continue as president and CEO of CBS.

The announcement was made after the stock market closed. CBS’ stock was up nearly 4% in aftermarket trading.

Viacom was up 8% in aftermarket trading. Philippe Dauman is the president/CEO of Viacom.

Shari Redstone, vice chair of the CBS board, as well as vice chair of Viacom and president of National Amusements, declined to take the top CBS chairman post “in light of her other professional and personal responsibilities.”

Moonves joined CBS in 1995 from Warner Bros Television and Lorimar Television. He has held positions as president of CBS Entertainment; president/CEO of CBS Television; and chairman of CBS Television.

In 2004, he became co-president/co-chief operating officer of Viacom. After Viacom's separation with CBS in 2006, he became president/chief executive officer of CBS Corporation.