Researcher at center of Facebook data scandal points finger at former Cambridge Analytica employee Dr. Aleksander Kogan says he is being used as a "scapegoat."

Aleksandr Kogan, the Cambridge University researcher who collected information on millions of Americans through Facebook for Cambridge Analytica, says both the social media giant and the controversial political research firm are using “revisionist history” to make him a “scapegoat.”

Kogan found himself at the center of a burgeoning scandal this week after a former employee of Cambridge Analytica, Christopher Wylie, told The New York Times that Kogan helped the firm exploit Facebook data Kogan had harvested through an app without users’ knowledge.

In an interview with ABC News, however, Kogan said it was Wylie who proposed the data-sharing agreement, assured him it was “totally legal” and even wrote the terms and conditions for the commercial version of the app.

“[He] guided us the whole way on what would be legal and appropriate,” Kogan told ABC News.

Facebook suspended Cambridge Analytica and Kogan from the social network last week pending an investigation into the breach of millions of user profiles, while Cambridge Analytica has denied any wrongdoing and blamed Kogan for violating Facebook's privacy terms.

Kogan claims both companies are treating him “unfairly.”

“Their position that they didn’t know and it was me and my company,” he told ABC News, “strikes me as entirely inconsistent with the facts.”

When asked for comment on the allegations made by Kogan, Wylie told ABC News Friday, “I have not hidden the fact that I was research director. I have not hidden the fact that I knew how the app worked."

"I’m not the one scapegoating Kogan," Wylie added. "Facebook is doing that. I’m taking my share of responsibility."

Wylie says he sounded the alarm because he was concerned about Cambridge Analytica’s role in the 2016 election. The firm was retained by the Trump campaign, but both the company and the campaign have said the Facebook data was not used as part of that work.

Democrats on the House Intelligence Committee have invited both Wylie and Kogan for interviews. Wylie has agreed to the meeting, and Kogan has yet to respond to the committee on the matter.

Kogan’s version of events differs significantly from the ones put forth by Wylie and Cambridge Analytica.

According to Kogan, Wylie approached him in 2014, about six months after Kogan's app launched. Eventually, the two would transform what Kogan says was originally intended to be an academic study for Cambridge University into a corporate market research project for SCL Group, Cambridge Analytica’s parent company.

Kogan said Wylie assured him the transaction would be legal and even offered to personally rewrite its terms and conditions to reflect its new commercial interests.

“Wylie told me it was ‘totally legal’ to share the data with them,” said Kogan. “They assured [me] that terms of service would be ones that allowed a broad license for usage, and this would be a completely commercial project.”

SCL Group purchased the data. Kogan declined to comment on the price tag but said he personally didn’t make any money at all. Ultimately, the firm received personal information from about 30 million Facebook users through the app, Kogan said.

Kogan does not appear to have explicitly alerted Facebook to the change of plans, but the app was updated and renamed. He says he wasn’t attempting to disguise its true intentions.

“It’s not like we changed [the app’s terms and conditions] somewhere [Facebook] couldn’t see. It’s on their system,” he said. “And their terms of service for developers state that ‘Hey, we will monitor your app, if we see any violations we’re going to notify you and audit you and all that stuff.’ And that never happened.”

Now Wylie, who told ABC News he left the company in late 2014, has painted a dark picture of his former employer, accusing them of “weaponizing the Internet” on behalf of their clients.

“Cambridge Analytica will try to pick at whatever mental weakness or vulnerability that we think you have and try to warp your perception of what’s real around you,” Wylie told ABC News. “If you are looking to create an information weapon, the battle space you operate in is social media. That is where the fight happens.”

Then another bombshell report appeared to bolster Wylie’s assertions.

On Tuesday, Britain’s Channel 4 News aired video of Cambridge Analytica CEO Alexander Nix appearing to court someone posing as a potential client by boasting about how the firm had sought to sway elections not only through digital micro-targeting but also bribery and entrapment. The claims in that report have not been independently verified by ABC News, but Nix was promptly suspended by the company’s board of directors.

Kogan, 31, was born in Moldova -- then a Soviet state — and immigrated to the U.S. with his family when he was seven years old. Later, he held an honorary associate professorship from the St. Petersburg State University in Russia, which he says entailed two or three trips to the university.

In an earlier interview with ABC News, Wylie said, "I think that it's really concerning that...the head psychologist that we were using, Aleksandr Kogan, was working on a Russian funded project in Russia on psychological profiling of people."

Kogan told ABC News that he is a U.S. citizen, but those ties have raised questions about whether this effort could have been connected to Russia’s broader effort to interfere in the 2016 election. Kogan says the speculation has only distracted from the real issue at hand: the privacy of personal data on the internet.

“Honestly, I think a lot of that is a sideshow,” Kogan said. “I think the Russian bit is quite ridiculous and really that’s what’s distracting us from the core issues that we really should have a conversation about, in terms of how do we use data, what do people know, what is appropriate and what does the general public feel comfortable with.”

"I was definitely part of the problem," Kogan told ABC News on Friday. "I operated in an era where what we did was normal, and I think a lot of developers thought was normal. We did not have a good pulse on how the broader public would react, and I think that's the bigger wake-up call."

He added, "Regardless of who wrote [the terms and conditions for the app]– was I misled on that end or not – I think that my responsibility personally certainly falls on not thinking well enough and not having a good enough understanding and anticipation of how the American public would react...to a product of our nature.I think that's a really broad problem that needs to be addressed by Silicon Valley, by developers and academics."

Editor's note: This story has been updated with Wylie's response to Kogan and Kogan's additional comments – both provided to ABC News Friday.