William Hill is reported to be backing an acquisition bid for OpenBet by its fellow provider NYX Gaming Group.
According to The Telegraph, OpenBet is being auctioned and investment firm Morgan Stanley is overseeing the process.
The Telegraph reported that OpenBet could be sold for between £250m and £300m.
It is also rumoured that Playtech is interested in buying OpenBet and Playtech declined to comment when contacted by Gambling Insider.
Vitruvian Partners, a private equity company, is the current owner of OpenBet, having purchased the company from digital pay TV provider NDS for £208m in 2011.
That buyout was led by OpenBet’s then CEO David Loveday, whose management team held a minority stake in the business as per the terms of the deal.
Loveday was replaced as CEO by Jeremy Thompson-Hill in 2013.
Provider Inspired Gaming Group is also owned by Vitruvian, having been acquired in 2010 for approximately £74.4m.