In a surprise twist, opposition research firm Fusion GPS says that it did not give its dossier of infamous anti-Trump research to BuzzFeed News prior to the outlet’s Jan. 10 publication of the salacious document.

That revelation, made in court papers filed by Fusion GPS’ lawyers in a Washington, D.C., federal court Tuesday, re-opens the issue of who provided the dossier to BuzzFeed.

Tracking down BuzzFeed’s source could prove crucial to several lawsuits that have been filed over the dossier.

Fusion GPS made the disclosure in a motion to quash a request for discovery made by Aleksej Gubarev, a Russian tech executive who is suing BuzzFeed for defamation. Gubarev was identified in a Dec. 13 memo contained in the dossier, which was written by former British spy Christopher Steele.

Gubarev’s lawyers have pressed Fusion GPS to provide details about its work on the dossier. A Hillary Clinton ally hired the firm last June to investigate Donald Trump’s activities in Russia. Fusion GPS then hired Steele to conduct the investigation.

In his Dec. 13 memo, Steele cites an unnamed source who claimed that Gubarev planted viruses and malware to hack into the Democratic National Committee’s computers. Gubarev has denied the allegation and says that BuzzFeed was careless in publishing the dossier without fully vetting Steele’s allegations.

It was widely believed that Fusion GPS was BuzzFeed’s source for the dossier.

The firm has acknowledged briefing reporters from outlets like The New York Times, The Washington Post, Yahoo! News and Mother Jones on the dossier. The existence of the dossier was an open secret in Washington, D.C., journalism circles. And last month, Fusion agreed to provide any communications it had with BuzzFeed regarding the dossier.

But Fusion now says that while BuzzFeed reached out to request the dossier, the firm did not provide the document to the news outlet.

“Fusion did not create or author the December Memo, and did not give it to Buzzfeed,” reads its latest court filing.

The filing also quotes from a deposition given in late September by Gubarev attorney Evan Fray-Witzer.

“We have not yet been able to depose Fusion. We’re making that attempt. Fusion’s fighting it. But the one thing that they have told us is Buzzfeed didn’t get the dossier from them. Buzzfeed went to them and tried to get the dossier from them and they refused to give it to Buzzfeed,” Fray-Witzer said in the deposition.

Fusion’s denial that it gave the dossier to BuzzFeed leaves a few possibilities for who disseminated the controversial document, which is now being investigated by Special Counsel Robert Mueller.

Steele has insisted that he is not BuzzFeed’s source.

The former MI6 agent disclosed earlier this year in a London court, where he is being sued by Gubarev, that he did not provide the dossier to BuzzFeed or any other media outlets. He claims that he has only provided the complete dossier to Fusion, British intelligence services and to David Kramer, an associate of Arizona Sen. John McCain.

During a meeting in London on Nov. 28, Steele gave the dossier to Kramer. McCain then gave the dossier to then-FBI Director James Comey during a Dec. 9 meeting. Fusion later instructed Steele to provide the final Dec. 13 memo to McCain and Kramer through an encrypted email channel.

Whether McCain or Kramer provided the dossier to BuzzFeed remains an open question.

Fusion GPS court filing by Chuck Ross on Scribd

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