The BT Pension Scheme (BTPS) has seen its exemption from the Pension Protection Fund (PPF) levy confirmed as unlawful state aid.

The UK’s second-largest pension fund had been appealing a 2013 ruling by the European Court of Justice (ECJ) that found it was incompatible with the single European market to be exempt from the lifeboat scheme’s levy, and therefore amounted to state support.

It followed an investigation by the European competition authorities in 2007 that led to then-competition commissioner Neelie Kroes to order an end to the PPF levy exemption.

In its judgement, the court said the appeal was “unfounded” and would be dismissed, ordering BT and the BTPS to cover all associated costs.

In a statement, the scheme said: “We welcome the clarity the judgement provides and have proceeded to date on the basis that the levy would remain payable.”

A spokesman for BT said it accepted, but was disappointed, by the court’s decision.

The ruling is the latest in a number of court cases for BTPS, which has been seeking to clarify in front of domestic courts the extent of the Crown Guarantee – a guarantee that would require the UK government to support the formerly state-owned company’s pension fund were it to become insolvent.

A UK Court of Appeal ruling from July found that the UK government would not be required to meet the costs of a buyout were the sponsor to collapse.