Pippa Middleton, 33, and her fiance James Matthews, 40, blocked publication of the photos.
Pippa Middleton, younger sister of Britain's Duchess of Cambridge, won a court injunction on Wednesday banning publication of 3,000 photos allegedly hacked from her iCloud account.
No details of the photos have been made public but newspapers have speculated they include images of the Duchess, Kate Middleton, her husband Prince William and the couple's children Prince George and Princess Charlotte, who are currently touring Canada.
The injunction obtained at the High Court by Pippa Middleton, 33, and her fiance James Matthews, 40, blocks publication of the photos.
"The evidence points towards its having been a flagrant and dishonest act which has caused the claimant some considerable distress," said Middleton's lawyer, Adam Wolanski.
Neither Middleton nor Matthews were in court.
Website designer Nathan Wyatt, 35, of Wellingborough, in the county of Northamptonshire in central England, has been arrested and bailed on suspicion of a Computer Misuse Act offence in connection with the case.
He has been ordered to return to a south London police station in November.