BT and TalkTalk will not be allowed to appeal the decision on their judicial review of the Digital Economy Act (DEA), the High Court has ruled.
The two Internet Service Providers (ISPs) won the right to a review of the controversial Act back in November, which would see alleged illegal filesharers have their internet cut off after "three strikes."
Their legal campaign was quashed when Mr Justice Kenneth Parker dismissed the case in April.
Yet, both BT and TalkTalk vowed to fight on, albeit dropping the claims against proportionality one of five issues they had with the DEA. They launched an appeal against the decision at the end of May.
However, their fighting words have been silenced yet again in the High Court this week, with Judge Sir Richard Buxton refusing to grant the appeal.
Tony Ballard, digital media specialist at law firm Harbottle & Lewis, said: "If it really marks the end of the litigation, its significance lies in Ofcom being able now to implement the procedure for discouraging peer-to-peer file sharing under the Digital Economy Act without the cloud of uncertainty as to the validity of the Act hanging over it."
"Opinion in the industry remains divided, however, as to whether the procedure is a good idea or not."
It may not be the end of the fight though, as Andrew Heaney, TalkTalk's director of strategy, told IT Pro.
"There are a number of options open to us and we are considering these," he said. "We still consider our challenge is sound."
A BT spokesperson merely added that the company was "considering our position."
The Digital Economy Act was brought in during the wash-up phase of the last Government in April 2010, drawing criticism it was rushed through without proper scrutiny.
