Selin Sinem Erciyas A recent ruling from a Turkish IP court breaks new ground in the ongoing battle for the European Patent Convention (EPC, 138/3) to be applied to patents in Turkey. The Turkish IP Law prohibits amendments or limitations of claims or patent documents after a patent has been granted. The only exception to this is changes made by the patentee during the national post-grant opposition phase, which was introduced in 2017. In line with the introduction of a post-grant opposition procedure, the IP Law prohibits any ruling to be made in a revocation action against a national patent while the post-grant opposition phase is ongoing before the Turkish Patent and Trademark Office. However, the law allows revocation actions to be heard and ruled against the validation of European patents while post-grant oppositions or appeal phases are ongoing before the EPO. Likewise, local courts are not obliged to deem EPO proceedings to be a prejudicial matter – this is entirely at the discretion of the judge.