BT has been given leave to revive its case against the Digital Economy Act, having been told earlier this year that they may not do so.
Late on Friday morning, the telco won permission to appeal against the outcome of a judicial review in April, when the High Court threw out almost all of BT and TalkTalk's claims that the act was incompatible with EU laws on privacy, freedom of information and the responsibilities of ISPs. The Appeals Court had said in June that such an appeal would not be allowed.
"We are pleased to have been granted permission to appeal the High Court judgment. We now expect that the hearing will take place as soon as possible," BT said in a brief statement.
A BT spokesman told ZDNet UK on Friday that a date had not yet been set for the appeal.
The Digital Economy Act, which was passed just before last year's general election, sets out a framework for cracking down on online copyright infringement. It requires ISPs to send the details of customers who are accused of infringement to rights holders, and potentially suspend the connections of those customers if they persist in sharing content without authorisation.
BT and other ISPs have argued that ISPs should not have to police their customers, and that the act's provisions could run counter to the privacy of internet users in the UK.