When you place the shroud of protection over an adjacent dying creature, [effect]. This effect lasts until the creature regains consciousness or dies, or until the shroud is removed (a standard action), whichever comes first.
Shroud of Protection/Revival, Adventurer's vault pg.177
Usually magic items need to indicate which parts interact with allies or enemies. However, it seems just too logical that everyone should be able to remove it with a standard action - thereby severely limiting it's usefulness.
Can the item be removed by someone who didn't activate the effect?