Its offer of £17.28 per share values the company at more than £30.45 billion. Fox offered £15.67 per share.
It came in a three-round auction was orchestrated by the Takeover Panel, which saw no movement in the battle to takeover the broadcaster.
However, the Murdoch Family Trust, which is in the process of selling the majority of 21st Century Fox to Disney, still owns 39 per cent of Sky. The Murdochs would then hold 5% in Disney.
Rupert Murdoch had been hoping that he would be able to take full control of the broadcaster he had established as a single channel European cable service in the 1980s, before commencing a four-channel satellite service from the Astra satellite in 1989.
A statement issued by 21st Century Fox read: “We note the increased cash offer for the fully diluted share capital of Sky by Comcast, and that it has been recommended by the Independent Committee of Sky. 21CF is considering its options regarding its own 39 percent shareholding in Sky and will make a further announcement in due course. Sky is a remarkable story and we are proud to have played such a significant role in building the incredible value reflected today in Comcast’s offer.”
Comcast had previously bid £14.75 per share, but had received relatively few acceptances, despite being ahead of the £14 per share bid by Fox.