The Australian Communications and Media Authority (ACMA) has found Telstra in breach of its carrier licence conditions on over 163,000 occasions after disclosing unlisted phone numbers of customers publicly.

The breaches occurred when the details of more than 140,000 Telstra customers who had requested unlisted numbers were made available to the public. The ASX-listed telco published 24,005 unlisted numbers, sometimes referred to as 'silent numbers', with corresponding customer names and addresses in the White Pages. ACMA said the company also included 139,402 unlisted numbers with customer details in its directory assistance database. Most of these incidents took place between 2021 and 2022, with some customers having their unlisted numbers and details included in both the White Pages and the directory assistance database.

"While we are not aware of any harm to people as a result of these breaches, Telstra failing to safeguard customer information, putting people's privacy and safety at risk, is a serious matter," said Samantha Yorke, ACMA member and consumer lead.

In response to the breaches, the ACMA has issued a remedial direction requiring Telstra to take actions to support compliance with obligations not to disclose or use information related to unlisted numbers. The company has been directed to reconcile its customer data with its White Pages and directory assistance database listings every six months, implement a training program for staff, and have its systems and compliance procedures independently audited.

"Telstra is entrusted with personal details of millions of Australians and those people have the right to expect that Telstra has robust systems and processes in place to ensure their information is being protected," Yorke added.

If Telstra breaches the direction, the ACMA may commence civil penalty proceedings in the Federal Court where Telstra could face pecuniary penalties of up to $10 million per contravention.