This happened a few minutes ago. Tee set a lock on items behind his shop, I went and bought the lock. The lock appeared as locked in my inventory (with chains). I had tried both dropping it and using it onto items of mine, and in both cases Tee was able to take the lock back. I think I even built a lock and set it on my items, and Tee was still able to take the lock. I don’t know how lock picking is supposed to work, but I guess it’s not supposed to work this way. Maybe after I bought his lock we have become able to take the locks of each other?