Viacom Inc. (VIAB) - Get Report  briefly shot up more than 15% in Friday's last few minutes of trading after The Wrap reported that the company and its former subsidiary CBS Corp. (CBS) - Get Report are engaged in merger talks more than a decade after the two companies split.

Viacom rose as high as $35.55 on the news, although it pulled back a bit to close at $33.76, up 9.7% on the day. CBS also rallied to as high as $59.44 before ending the session at $58.55, up 1.3%.

Shari Redstone, who is vice-chairwoman of both companies, is reportedly leaning heavily towards the merger. Les Moonves, chairman of CBS, has historically been opposed to a combination of the companies, but his stance on the issue has softened, according to TheWrap's sources.

"He's having active discussions with Shari and the board on a wide variety of issues all the time -- including this one -- and those discussions continue with regard to looking to merge the two companies," TheWrap quoted an individual close to Moonves as saying.

In late 2016, Redstone sent a letter to the boards of both companies from her parent company National Amusement, where she advocated for the merger "to respond even more aggressively and effectively to the challenges of the changing entertainment and media landscape." National Amusements holds nearly 80% of the voting common stock of both Viacom and CBS.

Viacom and CBS originally merged into a single company in 1999 before Sumner Redstone, Shari's father, split the companies up in 2005. Viacom has a market cap of $12.7 billion while CBS' market cap is $23.2 billion.

The renewed merger talk comes shortly after Walt Disney Co. (DIS) - Get Report agreed to purchase certain assets from 21st Century Fox (FOXA) - Get Report for $52.4 billion.