Electronic voting systems maker Smartmatic on Thursday sued Rupert Murdoch's Fox News cable network and Rudolph Giuliani, a lawyer for former President Donald Trump, claiming they defamed the company by falsely accusing it of helping to rig the US presidential election in favour of Joe Biden.
The suit, filed in New York County Supreme Court, also names as defendants former Trump lawyer Sidney Powell, Fox Corp and Fox hosts Lou Dobbs, Maria Bartiromo and Jeanine Pirro.
Smartmatic alleged that Fox and other defendants invented a story that the election was stolen from Trump and decided to make Smartmatic "the villain in their story".
"Fox News used the story to preserve its grip on viewers and readers and curry favours with the outgoing administration - one of their anchors was even able to get a pardon for her ex-husband," the lawsuit says, referring to Pirro.
The suit seeks more than $US2.7 billion ($A3.6 billion) in compensatory and punitive damages. Smartmatic also asks for defendants to retract "false statements and implications."
"We are proud of our 2020 election coverage and will vigorously defend this meritless lawsuit in court," a Fox News Media spokesperson said in a statement.
Florida-based Smartmatic's technology was only used in one place for the November 3 presidential election - Los Angeles County, which Biden won.
After the election, Trump and some of his supporters spread false claims of election fraud, including that Smartmatic and competitor Dominion Voting Systems manipulated the results.
Dominion Voting Systems has filed similar lawsuits against Giuliani and Powell.