BSkyB did not unduly discriminate against BT by blocking its multi-mullion pound TV advertising campaign to promote rival Premier League coverage, Ofcom has ruled.
BT complained to the media regulator in February after BSkyB refused to carry advertising on Sky Sports for its new BT Sport channels. BT Sport will be a new rival to Sky's long established sports services when they go on air in August.
But Ofcom dismissed the complaint on Thursday, ruling that BSkyB was "pursuing a legitimate commercial interest" by blocking promotion of a rival's sports coverage.
The decision will be a setback for BT, which is spending millions attempting to promote its new channels to football fans before the 2013/14 Premier League season kicks off on 17 August.
BSkyB said it was "pleased" at the result and compared BT's demands to "a bit like Tesco expecting to advertise inside Sainsbury's".
It is the latest dispute in a wider regulatory and marketing battle between BT and BSkyB over highly-lucrative TV coverage of top flight Premier League games.
The rejected complaint comes 24 hours after Ofcom launched a separate investigation into whether BSkyB was abusing its market dominance by withholding Sky Sports channels from BT's rival YouView pay-TV offering. That investigation was also prompted by a complaint from BT.
Graham McWilliam, BSkyB's group director of corporate affairs, said: "We are disappointed, but not surprised, that BT has again gone down the regulatory road rather than agree a commercial deal in customers' interests.
"However, we consider its latest complaint, like those that have gone before, to be entirely without merit."
BT, which spent £738m to snatch 38 top flight Premier League matches a season last year, claimed Sky is refusing to cut a deal unless the satellite broadcaster is allowed to bundle BT Sport into its existing subscription package for football fans.
A spokeswoman for BT said: "With regulation you win some and you lose some. Whilst this decision has gone against us, we are delighted that Ofcom is going to investigate Sky over their refusal to supply us with Sky Sports on YouView.
"That is a far bigger issue for us than their refusal to show our ads so this has been a good week for BT in terms of regulation."