Andrew Mountbatten-Windsor has won his legal case over police raids on his homes, the High Court has ruled.
A judge found the search warrants had not been lawfully issued when granted by an Old Bailey judge in February and therefore should be quashed.
Mr Justice Hilliard said Thames Valley Police had accepted the warrants had not been correctly granted when they were issued the day before the former Duke was arrested.
On Tuesday, The Telegraph revealed Mr Mountbatten-Windsor launched the legal case after accusing officers of seizing personal items during the raids.
He instructed lawyers after discovering detectives had allegedly removed private and confidential material unconnected to the criminal investigation.
The judge said his ruling does not mean material taken from Mr Mountbatten-Windsor’s properties has to be returned immediately as it is still the subject of an ongoing criminal investigation.