LONDON – Signaling a face-off between big state and big business in France, Gaul’s Council of State has overturned anti-trust approval of Canal Plus’ purchase of DTT channels D8 and D17 from the Bollore Group.

Put through in September 2012, the two-channel buy-up gave giant French paybox Canal Plus a valuable foothold in Gaul’s free-to-air broadcast sector. Canal Plus ownership has also helped turn D8 into an evermore frequent destination for U.S. series in France.

Ruling Monday, France’s Council of State dictated far more severe anti-trust limits on the number of French films Canal Plus’ – currently capped at 20 – can acquire for free-to-air channels D8 and D17, a youth channel, and its pay TV platforms.

Slamming the Council of State’s decision, Canal Plus said Monday night it had merely committed “an error of appreciation” in acquisition of French films for second and third-windows on its new free-to-air channels.

Canal Plus will now have to buckle under and work with France’s anti-trust authorities on stricter guidelines, to be up-and-running by July 2014.

Canal Plus’s purchase of D8 and D17 put the fear of God up its established commercial broadcaster rivals TF1, M6 and France Televisions. They feared that Europe’s second largest paybox would muscle in on key free-to-air program acquisitions, such as TF1’s top-rating U.S. series.

That was not paranoia. Canal Plus’ own ambitions for D8 are to make it a mid-size channel larger than the average Gallic DTT feed but not up to the scale of historic rivals.

D8 has, however, rapidly grown market share, thanks in part to Banijay H20’s “Ne Pas a Mon Poste,” an early evening talk show, securing a first half 2013 3.2% market share.

It also moved aggressively into U.S. series broadcast this fall, skedding free-to-air seasons of “Game of Thrones” and “Homeland” after their pay-TV bow on Canal Plus, and tying down runs to “Longmire,” “Cracked,” “Call the Midwife,” Chicago Fire” and “Ripper Street.”

Elsa Kesslasy contributed to this report