The BBC backed terrestrial digital TV system Freeview is now in 4.5 million homes - making it a significant competitor to Sky who, while still way ahead in the digital stakes with 7 million subscribers, are likely to be concerned that there is now another major player in the digital arena.
In his autobiography Greg Dyke, who spearheaded Freeview when he was BBC Director General, admitted his motivation for the free-to-air digital platform was the protection of the licence fee. If most viewers accessed TV via a Sky or cable style network (or ITV's now defunct subscription based digital TV platform) it would be possible to turn the BBC's output into subscription based channels. But with millions of Freeview boxes in circulation - providing digital TV without subscription - it would be hard to turn the BBC into a subscription service.