Rupert Murdoch is set to be questioned under oath as part of voting technology company Smartmatic's $US2.7 billion ($A4 billion) defamation lawsuit against Fox Corp over coverage of debunked vote-rigging claims involving the 2020 US presidential election.
Murdoch will be deposed in Los Angeles on Tuesday and Wednesday, according to a person familiar with the matter.
Murdoch, 92, had been the chairman of Fox Corp and News Corp before the companies announced in September that he was stepping down, becoming chairman emeritus of each company as of mid-November.
As part of the transition, his son Lachlan Murdoch became the sole chairman of News Corp and continues as the chair and chief executive officer of Fox.
Representatives for Fox News and Murdoch did not respond to requests for comment about the deposition.
A representative for Fox Corp declined to comment.
Florida-based Smartmatic is seeking damages from Fox Corp, Fox News and five individuals: Rudolph Giuliani and Sidney Powell, who were lawyers for Republican former president Donald Trump; and Fox hosts Maria Bartiromo and Jeanine Pirro, as well as former Fox host Lou Dobbs.
Smartmatic alleges in its lawsuit filed in state court in New York that the defendants knowingly spread false claims that the company's software was used to flip votes in favour of Democrat Joe Biden and against Trump.
Fox denies Smartmatic's allegations and has previously said the network had a right to report highly newsworthy allegations of vote fraud, and that airing fraud claims was covered by the US constitution's protections of a free press.
It also has called Smartmatic's damages claims outrageous and "not rooted in sound financial analysis".
Murdoch is not a named defendant in the case, but by establishing that he was involved in making decisions about Fox's coverage, Smartmatic would have a better chance of proving that Fox Corp is liable.
In order to prevail in a defamation case, Smartmatic must prove that Fox knowingly spread false information or recklessly disregarded the truth, the standard known as "actual malice".
Fox Corp and Fox News in April settled for $US787.5m another defamation lawsuit, brought by voting technology firm Dominion Voting Systems.
It was the largest-ever defamation settlement publicly announced by an American media company, according to legal experts.
Rupert Murdoch sat for a deposition in that case as well.
Australian Associated Press