A newly-released settlement from 2009 shows his accuser agreed not to sue any “potential defendant”.
The Duke of York’s lawyers will argue in a US court later that a civil sexual assault lawsuit should be dismissed.
Virginia Giuffre is suing him for allegedly sexually assaulting her 20 years ago, when she was a teenager.
A document made public on Monday showed convicted sex offender Jeffrey Epstein paid her $500,000 (£371,000) to end her claim against him – and agree not to sue any other “potential defendant”.
Prince Andrew has consistently denied the allegations.
While the settlement with Epstein does not mention the prince by name, his lawyers say the deal means she cannot sue him.
The interpretation of the 2009 document, disclosed by a New York court, will form a central plank of the argument in the civil case involving Prince Andrew.
Ms Giuffre alleges she was trafficked to the prince by Epstein and Ghislaine Maxwell – who was last week convicted of recruiting and trafficking young girls to be abused by the late financier.
Financier Epstein died in prison in 2019.
Ms Giuffre’s legal team say the terms of the Florida settlement are irrelevant to her case against the prince – which alleges sexual abuse by the royal in New York, London and the US Virgin Islands.
In her 2009 claim against Epstein, lawyers for Ms Giuffre said she was lured into a world of sexual abuse at his Florida home when she was a teenager.
They added: “In addition to being continually exploited to satisfy defendant’s [Epstein] every sexual whim, [Ms Giuffre] was also required to be sexually exploited by defendant’s adult male peers, including royalty, politicians, academicians, businessmen and or other professional and personal acquaintances.”
That case never went to trial because on 17 November 2009, Epstein agreed to pay her $500,000 to stop it in its tracks. That deal had been confidential but has now been made public because of its potential importance to the Prince Andrew case.
In the document, Ms Giuffre, also referred to by her unmarried name Roberts, agreed to “release, acquit, satisfy, and forever discharge” Epstein and “any other person or entity who could have been included as a potential defendant”.
The settlement’s wording says she discharges the potential defendants from any US legal action, including damages claims dating “from the beginning of the world”.
The precise meaning of that wording is expected to be the subject of intense legal arguments in New York on Tuesday.
In filings to the New York court last month, Andrew B. Brettler, the prince’s lead lawyer, said of the settlement: “Epstein negotiated for this broad release, insisting that it cover any and all persons who Giuffre identified as potential targets of future lawsuits, regardless of the merit – or lack thereof – to any such claims.
“Giuffre’s baseless claims against Prince Andrew… must be dismissed at this stage.”
In a statement, one of Ms Giuffre’s lawyers, David Boies, said the settlement was not relevant to her claim and “does not mention Prince Andrew”.
“He did not even know about it,” he added.
In a previous court filing, her lawyers said that the Epstein deal was “outside the four corners” of her action against Prince Andrew because it does not cover her claims against him.
Judge Lewis A Kaplan, who is presiding over the civil case, will hold a video teleconference later.