Not A Wax Or Gum Stain - So What Is It?

I decided to pick this card up just because of whose card it is.  It's Twitter's own John Bateman!

What's interesting to me is the back of the card.

At some point, whether in a pack or a box at some point in the next 50 years, the 1966 Tim McCarver Rub-Off was behind it.  It appears they did actually rub off.

So, what do we call this "stain?"  There have to be many more of these out there.

If you shop online and haven't signed up and used ebates yet, you're missing out.  I also use it on eBay to get money back from purchases there.  Between referrals and cash back, I've gotten over $100 in about seven months.  FREE CARDS!  If you're on Twitter, please give me a follow.  Happy collecting!

DBBD: 1972 Topps #5 John Bateman

It's not every day that I come across a John Bateman card.  When I do, I chuckle because you can follow him on Twitter.

1972 Topps #5 John Bateman