Sgt Knox Debuff "Will not Fail"

Hey folks! Just started up an alt as a GF and ran my first demo, and poof, out comes an epic Sgt Sgt, bound to account. So here's my question, does anybody know if the 30% damage reduction only applies to the companion or does it look while so to the Summoner? Not sure if this is been tested on Act, but any links would be much appreciated. Thanks!