Fleer Star Stickers

A couple days ago Captain Canuck had a post on these here.
He was looking for some to finish his set.I mentioned that I had one he needed but it has a strange mark on it. I'm not sure what to make of it.It was not added on to the card after printing.It may be just a spec on the plate or just on this one card but the red "C" is so precise it looks like it was done on purpose.

Does anyone have any ideas ?