The man who built the app that helped Cambridge Analytica to collect the data of tens of millions of Facebook users is suing the social network, claiming that the company defamed him when it said that he had lied about what the plans were for the data.

Aleksandr Kogan, an academic and former research associate at the University of Cambridge, obtained the data of Facebook users via an app called ‘thisisyourdigitallife’ before then passing on this data to Cambridge Analytica. Facebook has always claimed that Kogan said the data would be used for academic purposes.

However, Kogan argues that his app did have a fine print that said the information could be used commercially. Nonetheless, this still would have been a breach of Facebook’s rules.

“Alex did not lie, Alex was not a fraud, Alex did not deceive them, this was not a scam,” said Steve Cohen, a lawyer for Kogan, according to The New York Times. “Facebook knew exactly what this app was doing, or should have known. Facebook desperately needed a scapegoat, and Alex was their scapegoat.”

Cambridge Analytica hired Kogan in June 2014 – the same month the company was founded by Republican donor Robert Mercer and former Donald Trump advisor Steve Bannon. The company collected data to identify the personalities of Facebook users and use that to influence their politics-related behaviour.

The scandal affected as many as 87m users and, as result, Facebook is facing investigations in various locations across Europe and North America, while Cambridge Analytica shut up shop last May.