Guild Wars 2

…the orb refuses to acknowledge new ownership.

Try having one of the members from your team pick up the orb then place it back on to the alter of power or on a different alter of power in a different keep. Also if none of these work pick up the orb of power then drop it and let it reset in the cradle of power after 15 min timer. If none of these work then post back the results to confirm that there was a bug.