The Office of the Australian Information Commissioner (OAIC) initiated legal action against Facebook over allegedly disclosing the personal data of more than 300,000 users to a third-party application associated with Cambridge Analytica.

In a filing to the Federal Court of Australia, the regulator claimed Facebook had “seriously and/or repeatedly interfered with the privacy of approximately 311,127 Australian Facebook users” between 12 March 2014 and 1 May 2015, by sharing their personal information to the This is Your Digital Life app, which was then allegedly used by Cambridge Analytica for political profiling.

OAIC stated most of the affected users did not install the app themselves, and their data was disclosed via their friends’ use of the app.

It accused the social media giant of not taking “reasonable steps during this period to protect its users’ personal information from unauthorised disclosure.”

Australian Information Commissioner and Privacy Commissioner Angelene Falk commented the affected users’ data was “exposed to be sold and used for purposes including political profiling, well outside users’ expectations”.

She added the affected users were unable to control disclosure of their personal data due to “the design of the Facebook platform.”

The authority said the country’s Federal Court might impose a civil penalty of up to AUD1.7 million ($1.1 million) for each data breach.

Facebook was shaken by a major scandal eruption in March 2018, when reports revealed the data of 50 million users was harvested by political consulting company Cambridge Analytica ahead of the US elections in 2016.