Historical Rules · 13 July 2018
Rule 702.16m
Official source text from the 13 July 2018 Rules release
Some Auras both give the enchanted creature protection and say “this effect doesn’t remove” either that specific Aura or all Auras. This means that the specified Auras can legally enchant that creature and aren’t put into their owners’ graveyards as a state-based action. If the creature has other instances of protection from the same quality, those instances affect Auras as normal.