More than 100,000 former and existing Optus customers have signed on to a class action against Optus, claiming the telco breached privacy, telecommunication, and consumer laws.

The class action, launched by Slater and Gordon, says Optus “failed to protect or take reasonable steps to protect customer data from unauthorised access or disclosure, failed to destroy or de-identify former customers’ personal information, and failed to ensure legitimate access to the data.”

This resulted in the September 2022 cyber attack, in which personal information of up to 10 million Aussies was stolen, including customer names, dates of birth, phone numbers, email addresses, postal addresses, driver’s licences, Medicare cards, and passport numbers.

“Optus has also been accused in the class action of breaching contractual obligations to customers along with its duty of care to ensure customers did not suffer harm arising from the unauthorised access or disclosure of their personal information,” Slater and Gordon said.

Slater and Gordon’s Ben Hardwick said it was “an extremely serious privacy breach both in terms of the number of people affected and the nature of the information that was compromised”.

“Very real risks were created by the disclosure of this private information that Optus customers had every right to believe was securely protected by their telecommunications and internet provider.”

Hardwick told ABC News Breakfast this morning Optus should have had “much better systems” in place.

“At the time, the Minister for Cyber Security said Optus had effectively left the window open for cyber hackers to get into the window,” Hardwick said.

“Optus came out in response and said this was a sophisticated attack and we have been conducting an investigation and we have come down that this is something that should not have happened.

“Optus should have had much better systems in place. Optus is a very large company, it has data important to Australians, it should have had systems in place that prevented this type of incident from happening.”

“We have had women who have been victims of domestic violence, victims of stalking, and their stories about why their private information is so important to them are very concerning.

“Over the last six months, Australians have seen a real rise in the number of scams and attempted frauds on their accounts, so increasingly people are really worried about their information.”