I have a portal where this happened:
Player A conquered the portal, placed one resonator. Player A was listed as owner.
Player B, C and D placed more resonators. B is listed as owner.
Currently there's still the one resonator from A, two resonators are from C, five resonators are from D. And two mods from B and one mod from C.
So how is portal ownership (for the Guardian badge) decided? Is the owner the player who initially conquered the portal and still has one resonator in it or can it change?