By OLIVIA RUBIN and MATT MOSK, ABC News

(WASHINGTON) — The Colorado voting machine company that fringe pro-Trump forces have targeted with dark conspiracy theories of a rigged 2020 election is demanding that conservative lawyer Sidney Powell retract the “wild, knowingly baseless, and false” allegations she has made against them.

Dominion Voting Systems made their demands in a letter to Powell, who has taken a central role in pushing the debunked theory that dark forces rigged Dominion machines to flip votes from Trump to former Vice President Joe Biden.

The company’s letter represents its most aggressive posture to date, and signals the early stages of what could become heavy and costly pushback against the lawyers who have led a post-election campaign to discredit the 2020 election results. Pro-Trump attorneys have filed more than 60 lawsuits as part of the effort, nearly all of which have been dismissed, often with sharply-worded rulings.

Despite having been repeatedly disputed by the company and disproven by federal election officials, the bogus conspiracy theory has spread fast and wide on social media and in conservative media outlets.

Powell made the claims in the pages of post-election federal lawsuits filed in four states, all of which were forcefully rejected by judges.

“While you are entitled to your own opinions, Ms. Powell, you are not entitled to your own facts,” Dominion attorney Thomas A. Clare wrote in the letter, which also asks Powell to preserve any documents and messages related to the matter.

“As a result of your false accusations, Dominion has suffered enormous harm, and its employees have been stalked, have been harassed, and have received death threats,” Clare wrote. “For the safety of Dominion’s employees and for the sake of the truth and confidence in American democracy, we demand that you immediately and publicly retract your false accusations and set the record straight.”

Dominion’s voting machines are used in 28 states across the country, some of which were won by Trump in this year’s election.

Numerous legal experts have told ABC News the legal effort to overturn results in the 2020 presidential election bordered on abusive. This week the attorney general in Pennsylvania said he was looking into sanctions against attorneys who brought nearly two dozen election lawsuits in the state.

“Attorneys who try to disenfranchise Pennsylvania voters based on frivolous allegations should be held accountable,” a spokesperson for Pennsylvania Attorney General Josh Shapiro told ABC News. “We’re continuing to explore our options and will not hesitate to take action if we conclude it is warranted.”

ABC News has not received a response from Powell about the Dominion letter.

Powell, who rose to prominence last year defending Trump’s embattled former national security adviser, retired Lt. Gen. Michael Flynn, was publicly removed from the Trump legal team earlier this month after her claims began veering into far more conspiratorial territory. But Trump has continued to embrace her legal effort on social media.

ABC News’ Ali Dukakis contributed to this report.

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