Representatives for the opposition research firm behind the so-called Trump dossier are scheduled to appear for a deposition in Washington, D.C. on Wednesday as part of a defamation lawsuit against BuzzFeed News.

But Fusion GPS, the firm that compiled the salacious and uncorroborated document, is not going to the deposition without a fight. Last week, its lawyers filed a petition asking a federal judge in Washington, D.C. to quash a subpoena that had been issued for a deposition as well as for records about the dossier.

In lieu of blocking the subpoena, Fusion asked the judge, Tanya Chutkan, for a protective order limiting what questions can be asked of the firm. Chutkan had not weighed in on the request as of early Wednesday morning.

The subpoena against Fusion was obtained last month by Aleksej Gubarev, a Russian tech executive suing BuzzFeed for publishing the dossier.

The 35-page document, which BuzzFeed published on Jan. 10, contains 17 separate memos dated from June 20, 2016, and Dec. 13, 2016. The final memo alleges that Gubarev and his tech companies used computer viruses and bots to hack into the Democratic National Committee’s email systems.

Gubarev, who has vehemently denied the allegations, filed his lawsuit against BuzzFeed in February. He has also filed suit in England against Christopher Steele, the former British spy who authored the dossier. Steele had been hired by Fusion GPS last June. The firm was working on behalf of a political ally of Hillary Clinton’s after having first been hired to investigate Trump’s background in September 2015 by a Republican donor.

Numerous questions about the dossier remain unanswered, including the identities of Fusion’s political clients, the identities of Steele’s sources, and how exactly BuzzFeed obtained the dossier.

In its latest filings, Fusion GPS provides a hint that it gave the dossier to BuzzFeed. The firm states in the court documents that it is willing to provide “pre-publication communications with BuzzFeed” concerning the dossier.

The idea that Fusion GPS gave BuzzFeed the dossier would not be a major surprise. But so far, neither company has disclosed how the dossier was transferred to BuzzFeed.

Fusion remained tight-lipped about the identities of its clients and of Steele’s sources.

The firm has repeatedly declined to identify its clients, most recently during an interview that the firm’s co-founder, Glenn Simpson, gave to the Senate Judiciary Committee. Simpson, a former Wall Street Journal reporter, was interviewed by the committee last month for 10 hours.

Fusion GPS asserts in the filing that identifying its clients would “undermine, deter, and chill” its “rights to engage in political activity and political speech, to speak anonymously, to associate freely with others, and to petition the government.”

Fusion also asserts that identifying its clients “would expose those clients to significant harassment.”

To help bolster its argument, Fusion provided a declaration from a former client — a national attorney writing anonymously as “John Doe” — attesting that he would not have hired the firm without assurances that his identity would be protected.

“Had I known that my affiliation with Fusion GPS would not be kept confidential, I would not have worked with them,” stated Doe.

Fusion also declined in the court filings to disclose the identity of sources for the dossier, arguing that doing so “could put those individuals in grave and life-threatening danger.”

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