Apple has launched a new legal challenge in the UK against a Home Office request for access to encrypted iCloud data held by British users. The complaint is filed at the Investigatory Powers Tribunal (IPT), an independent court that examines claims about the legality of actions by UK intelligence and security services.

According to reports, the challenge follows earlier government action in this dispute. The Home Office previously agreed to drop an earlier demand, which would have applied more broadly, after tensions involving the United States. The UK then issued a new technical capability notice (TCN) intended to require Apple to provide a form of access limited to users in the UK.

TCNs are issued under the Investigatory Powers Act and can require companies to assist UK security services, including in ways related to accessing data that Apple describes as highly encrypted. Apple argues that any so-called “back door” access would weaken security for users. The court has notified privacy and legal groups, including Privacy International and Liberty, which are also involved in related litigation concerning these notices.

Neither Apple nor the Home Office discusses the details of the technical notices publicly, and the scope of the latest complaint has not been fully reported.