Singtel's (SGX:Z74) Australian unit, Optus, was informed by the Australian Communications and Media Authority about proceedings in the Federal Court of Australia against it over an alleged breach by Optus Mobile over several provisions of the Telecommunications Determination 2019.

The proceedings have reported 1,005 breaches, which happened on Sept. 18, 2025, according to a Thursday filing with the Singapore Exchange.

The unit is reviewing the pleadings and will respond in due course.

Additionally, the company is unable to determine the scale of potential penalties at this stage.