"of Puncturing"

[LavCat]

Does anyone know the detailed mechanics of the suffix "of Puncturing"? Is "of Puncturing" the same property as the reduction in defense per hit of the Malice runeword? Does the punctured target ever regain its lost defense? Can punctured defense ever go below zero? Does actual damage have to be inflicted in order to puncture? Does puncturing work with a ranged attack (such as Blade Fury)?

Thanks for any help!