Sky plc (SKYAY) shares surged to the top of the FTSE 100 Friday, after reports that Comcast (CMCSA - Get Report) and Verizon (VZ - Get Report) had joined the pursuit for 21st Century Fox (FOXA) .

Sky shares gained 2.49%, changing hands at 925 pence, the stocks biggest gain since June and outpacing the 0.18% decline for the FTSE 100 Friday.

Fox owns a 39% stake in Sky and is in the midst of a proposed, and contentious, $15.3 billion bid to buy the near 60% it doesn't already own.

Comcast is reportedly interested in buying a substantial piece of 21st Century Fox, while Verizon's interest is still in the preliminary stages, The Wall Street Journal reported. The move follows discussions between Disney (DIS - Get Report) and the Rupert Murdoch-owned media conglomerate.

Fox Hunt Widens as Comcast, Verizon Reportedly Join Disney Pursuit

Fox share gained 9.17% in after-hours trading after the reports came to light.

Assets potentially for sale include Twentieth Century Fox studio, U.S. cable operations and international businesses. Fox news, the company's sports channels and Fox broadcast network haven't been included in the talks, the Journal reported.

In Friday note Liberum analysts said that Comcast would likely be interested in Fox's 39% stake in Sky, as NBC Universal has publicly stated its interest in expanding its non-U.S. assets and the UK is a key market.

Liberum analysts said the interest is a positive for Sky, as it shows that major U.S. groups are interested in the asset, "demonstrating that many media groups still see the Sky asset as a very valuable one to own."

It is unclear whether either company would be willing to go on with Fox's proposed acquisition of Sky. The contentious takeover was referred to the U.K.'s Competition and Markets Authority in September by Culture Secretary Karen Bradley.

The CMA is calling for submissions on Fox's "genuine commitment" to broadcasting standards and whether the acquisition by Fox will reduce media plurality and access to differing voices, the CMA also said it contacted Ofcom, the government's separate media regulator, to ask for information and factual and technical assistance.

More of What's Trending on TheStreet: