(AFP) - King Charles III's younger son made headlines earlier this year when he flew in from California to make an unexpected in-person appearance at the High Court in London for the case.
The prince and six other high-profile figures including pop star Elton John launched the legal action last year after becoming aware of "compelling and highly distressing evidence that they have been the victims of abhorrent criminal activity and gross breaches of privacy" by Associated Newspapers Limited (ANL).
Other claimants are John's husband, David Furnish, the actors Liz Hurley and Sadie Frost, politician Simon Hughes, and Doreen Lawrence, whose son Stephen was killed in a racist murder in 1993.
Lawyers for ANL -- publishers of the Daily Mail and Mail on Sunday -- had argued the claims against them had been brought too late.
But in a written ruling, Judge Matthew Nicklin disagreed and said the case could go ahead.
The ruling is the latest chapter in Harry's turbulent relationship with the press, whom he holds responsible for the death of his mother Princess Diana in a 1997 Paris car crash as she fled paparazzi.
ANL had "not been able to deliver a 'knockout blow' to the claims of any of these claimants", the judge said in his 95-page ruling.
"In my judgment, each claimant has a real prospect of demonstrating that Associated... concealed from him/her the relevant facts upon which a worthwhile claim of unlawful information gathering could have been advanced," he wrote.
Breach of privacy
Harry and the other claimants accuse ANL of methods such as hiring private investigators, tapping phone calls and impersonating individuals to obtain medical information for articles.
The court has been told the alleged wrongdoing dates back to 1993 and continued to as late as 2018.
ANL has dismissed the allegations, arguing the case should not go to trial.
It said in response to the judge's ruling on Friday that the claims against it were "lurid".
"We look forward to establishing this in court in due course," it added.
Welcoming the ruling, Harry and the six other complainants said they were "delighted".
The judgment would allow "our claims over serious criminal activity and gross breaches of privacy by the Mail titles to proceed to trial", they said in a joint statement.
Actor Hugh Grant, a leading member of the press reform campaign group Hacked Off, called it a "significant blow to the Daily Mail and great news for anyone who wants the truth about allegations of illegal press practices to come out".
Harry, 39, and his wife Meghan, 42, quit royal duties in 2020 and relocated to California, in part blaming media attention for the move.
The prince, who is formally known as the Duke of Sussex, has vowed to make reforming the British media his life's mission.
The case is one of several legal battles he is waging with different UK newspapers over privacy concerns.