J.K. Rowling revealed Albus Dumbledore as the owner of the Elder Wand before his death.
The Elder Wand is one of the three Deathly Hallows and is described as the most powerful wand in existence. Dumbledore defeats Gellert Grindelwald in 1945 and takes possession of the wand, later using it during his long career as a wizard and Hogwarts headmaster.
Dumbledore’s ownership becomes central to Harry Potter and the Half-Blood Prince and Harry Potter and the Deathly Hallows. Dumbledore arranges for Severus Snape to kill him on the Astronomy Tower, but because the death is planned, Snape does not truly win the wand’s allegiance through that act. Draco Malfoy has already disarmed Dumbledore, making Draco the wand’s master.
Harry later disarms Draco at Malfoy Manor, so the Elder Wand’s allegiance passes to Harry. Voldemort misunderstands this chain of ownership when he takes the wand from Dumbledore’s tomb. The wand’s physical possession and its magical allegiance are therefore not always the same thing.