Personalized?

Okay this is bizarre. I've had a personalized one so I edited this earlier according to my findings. However, just now someone traded to me an axe that had Weekend on it. My axe was not tradeable but his was. What's going on here?

Perhaps it becomes personalized when it's equipped? I've heard rumors like that anyways.

That could be it... I had my secondary slot empty when I first got it so it just auto equipped. If I get another I'll test since it doesn't seem like anyone wants to buy it anyway, lol.