Item Weight Issue

[Mordicil]

I play a necromancer and I gave my pet a sword. When I did, I noticed that the weight in my inventory did not go down. Even though my pet was holding the sword, the game treated as though I was still holding it. After dismissing the pet the weight disappeared from my inventory. Is it supposed to do that or is it a glitch? Thank you for your help and sorry if someone else already posted a thread about this issue.