Cambridge University has criticised Mark Zuckerberg's testimony before US Congress after the Facebook founder suggested "something bad" may have taken place in the way researchers used private data collected on his platform.
A spokesman said the university has been publishing research based on Facebook data for years, sometimes in collaboration with Facebook employees, and stressed the social media giant has yet to provide evidence for its claims.
The university said in a statement: "We would be surprised if Mr Zuckerberg was only now aware of research at the University of Cambridge looking at what an individual's Facebook data says about them.
"Our researchers have been publishing such research since 2013 in major peer-reviewed scientific journals, and these studies have been reported widely in international media.
"These have included one study in 2015 led by Dr Aleksandr Spectre (Kogan) and co-authored by two Facebook employees.
"We wrote to Facebook on 21 March to ask it to provide evidence to support its allegations about Dr Kogan. We have yet to receive a response."
Dr Kogan, who also uses his married named Spectre, is accused of giving the private information of tens of millions of Facebook users to controversial election consultants Cambridge Analytica (CA) after collecting it via a Facebook app in 2013.
A market research manager at Facebook, Pete Fleming, and Dr Kogan were among the co-authors of a 2015 study which used Facebook data on almost 60 billion friendships to understand issues around social class and relationships.
It used the same methodology to collect its data as Dr Kogan is alleged to have used to collect Facebook data which may have been shared with CA.
Mr Fleming is now head of research at the Facebook-owned photosharing app Instagram.
Mr Zuckerberg said he was "looking into" the prospect of taking legal action against Dr Kogan, Cambridge University and CA during questioning by the US Congress committee on energy and commerce in Washington on Wednesday (April 11).