Originally posted by Surtur
The only way it wouldn't work properly for Grindelwald is if he wasn't accepted as the true owner. It makes sense he wouldn't be when you think about it...he stole the wand right? I don't think he used magic to disarm someone of it.But whatever reason he wasn't accepted as the true owner...that would mean anyone who defeats Grindelwald wouldn't have become the true owner either. So why did Dumbledore seem to have control over it?
Okay, the Elder Wand can only be fully controlled if the previous owner of this gets defeated in duel by the current opponent.
Gellert Grindelwald stole the Elder Wand. Which cause the Elder wand to reject him.
Similarly, we saw that Voldemort couldn't use the Elder Wand, since he wasn't the wizzard who killed Albus (Remember that Severus Snape was the one who killed Albus).
So when Voldemort used the Elder Wand, it broke.
Later we see that Voldermort kills Snape, and is finally able to use the Elder Wand.
https://www.youtube.com/watch?v=8cL527bg0II
See, Voldemort himself confirms it. So Voldermort killed snape to have control over the Wand.
So that means that neither Gellert nor Tom had control over the wand. However in the end Voldemort did had control over the wand.
Remember that Albus defeated Gellert, which makes him the owner of the wand.