sethm said:
No- definetely an ink stain.
I was just curious if this happens during manufacturing process and shipping.
If it is in a sealed box, it isn't going to happen during shipping. If it was there when you opened the box, then it happened before the box was sealed. Many bad things can happen in a factory, though, obviously, they are interested in minimizing the occurrence of such problems.
Do you have any small children by any chance? People have been known to be sloppy with ink and other substances, and they do not always confess to their mistakes. Since you did not notice it right away, it is possible that someone put it there while in your possession.
Anyway, you were wise to get suggestions from LG for how to deal with this.