A two-day hearing to determine who will pay the estimated £50m costs of the case will be held on July 29.
The Duke and his fellow claimants were warned by the judge last year that the financial consequences of the legal battle could be substantial if they were defeated.
The seven claimants have insurance of up to £14.1m to cover their bills, the court heard previously.
In his 436-page ruling, the judge rejected the claimants’ argument that simply because the information was private and the publisher could not explain how it had been sourced, the relevant articles “must have been unlawfully sourced”.
He found that the journalists who gave evidence provided “lawful explanations” for the sourcing of each of the 50-plus disputed articles, which were accepted by the court.
Mr Justice Nicklin was also critical of the “legal research team” behind the claim, finding its evidence “inconsistent” and “unconvincing”.
‘A magnificent vindication of our journalism’
Associated Newspapers welcomed the ruling, describing it as “an overwhelming victory for The Daily Mail and its journalists, and for a free press generally”.
It added: “Mr Justice Nicklin today cleared The Daily Mail and The Mail on Sunday, and dismissed every single one of the 97 allegations made by the claimants.
“In every case, the judge accepted the honesty of our journalists’ evidence on how they sourced their stories. This is a magnificent vindication of The Daily Mail’s journalism.
“For some of the most outrageous allegations made when the case was launched in a blaze of publicity four years ago – placing bugs in people’s cars and homes, listening to calls as they were made and illicitly accessing bank accounts – no credible evidence was ever presented.”
‘ The preceding article may include information circulated by third parties ’
‘ Some details of this article were extracted from the following source www.telegraph.co.uk ’
