The Duke of Sussex is appealing against his High Court defeat in a £50m phone-hacking case against the publishers of the Daily Mail.
Prince Harry, together with five co-claimants, has applied to the Court of Appeal for a new hearing after losing the privacy action against Associated Newspapers in July.
Sir Elton John, his husband David Furnish, Elizabeth Hurley, Sadie Frost and Baroness Lawrence are also appealing.
Simon Hughes, the former Liberal Democrat MP, is the only one of the original claimants who is not choosing to appeal.
In a statement, Callum Galbraith, their lawyer, said: “We confirm that the claimants have today filed applications with the Court of Appeal for permission to appeal the judgments of Mr Justice Nicklin in respect of his dismissal of their claims and the indemnity costs order.
“The claimants respectfully disagree with those unprecedented decisions, which they consider to be legally and factually flawed.”
The group sued Associated Newspapers Limited in relation to allegations of phone hacking, blagging private medical records and other alleged illegal information gathering.
Associated strongly denied the claims, which were heard at an 11-week trial in London earlier this year, with Justice Nicklin dismissing all 97 claims made by the original seven claimants in a judgment on July 7.
He said their entire case was based on inference rather than evidence, and accepted the journalists’ “lawful explanations” for how their stories were obtained.
In a decision in August, the judge ruled that the group had to pay £9.5m within seven days as an initial contribution to the publisher’s costs before further hearings to determine the total sum.
It will now be up to the Court of Appeal to decide whether to grant a new hearing. Prince Harry and his co-claimants will need to convince the court there are reasonable grounds to believe that Justice Nicklin’s decision was wrong.
The decision on granting a full appeal hearing will be down to a single Court of Appeal judge, basing their decision on written submissions from the claimants’ legal team. If permission to appeal was granted, a full hearing would take place in front of three judges.
The claimants are also appealing against the judge’s order that they must pay the publisher’s legal costs over and above what had been agreed before the case started.
Justice Nicklin said the case merited higher costs being paid by the losers because their claims had been “unreasonable to a high degree”. The claimants are facing a total bill of up to £34.5m for the publisher’s legal costs.
If they succeed in securing an appeal hearing, the already astronomical bill would rise even further.
‘Conspiracy against the press’
The Duke criticised the judge’s decision at the time, describing the 426-page ruling handed down by the High Court as a “complete and obvious whitewash”.
Paul Dacre, the editor-in-chief of Associated, condemned the “confused and angry” Duke for bringing the failed claim that formed part of a “conspiracy against the free press”.
He said Prince Harry had been persuaded by campaigners to launch a “trumped-up action” that should “never” have reached trial.
The Telegraph revealed last month that the law firm at the heart of the failed claim had gone bankrupt.
Mark Thomson, who founded the company in 2009 and owned 100% of the shares, served as a co-ordinating solicitor for the whole group and personally represented Frost and Sir Simon.
In total, seven lawyers from the firm worked on the case.
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