BSkyB may have to sell some or all of its stake in ITV at a loss after the Competition Commission found that its 17.9 per cent holding in the commercial broadcaster was “against the public interest”.

The commission said that it may force BSkyB — 39.1 per cent owned by News Corporation, parent company of Times Online — to sell some or all of its stake, in the light of a further round of consultation.

“Sky has got 17.9 per cent, and we’ve found that causes problems,” Peter Freeman, the chairman of the Commission, said.

“Divestment looks to be the remedy and we are discussing the level.”

The watchdog is looking at levels just below 10 per cent and 15 per cent as alternatives to a full sale.

The satellite broadcaster seized the stake in ITV for £940 million, or 135p a share, in November last year, when NTL, its pay-TV rival, was trying to mount a takeover.

If it were forced to sell at yesterday’s 105p, it would recoup £730 million, crystallising a loss of more than £200 million.

Mr Freeman made clear that he did not expect to revisit the in-principle findings in the final ruling, which is due in December, although the remedies were up for grabs.

He said that the regulator would take into account only new information: “We don’t publish these arguments for people to take a cockshy at.”

The final decision on remedies rests with John Hutton, the Business Secretary.

However, he is bound to accept the commission’s findings in principle and it would be a big political step if he were to reject the regulator’s proposed solution.

The commission concluded that Sky’s stake was enough to give it “a material influence” over ITV.

It said that Sky would “have an incentive to reduce ITV’s investment in content in order to reduce the competitive constraint” of free-to-air broadcasting and that the satellite broadcaster could “influence the course of any future transactions” — that is, mergers or takeovers.

The regulator accepted the concerns raised by Michael Grade, the executive chairman of ITV, that Sky could block shareholder resolutions requiring 75 per cent support because not all shareholders vote.

Many deals need a 75 per cent vote at some point, because they require the issue of many new shares or, in the case of takeover, by means of a scheme of arrangement.

It is rare for British competition authorities to conclude that there is “material influence” at such a low level of shareholding.

However, Becket McGrath, a competition lawyer at Berwin Leighton Paisner, said: “It’s certainly a grey area, in the zone, but at the low end.

"However, in the end, maybe Sky got what they wanted, blocking Virgin Media at the cost of £200 million.”

Sky took comfort from the fact that the commission dismissed other objections.

It said that the shareholding had no anticompetitive impact on the existing market for television advertising, the bidding for sports rights, or plurality in television news — the last of which had been the source of public interest concerns raised by Ofcom.

A spokesman for Sky said that it welcomed “the commission’s provisional findings that a minority investment in ITV does not raise public interest concerns with respect to plurality” and added that it would engage further.

ITV said that it was looking forward to working with the commission “so that issues arising from BSkyB’s stake can be addressed”.

Its shares rose 3.8p to reach 105p.

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