2007 Topps Baseball "No Name" Variation?

I am continuing to go thru my large stash of cards purchased off C-list, and I was going thru a large run of 2007 Topps baseball, when I ran into a chunk of 50 or so where the team name and player name are not visible on the front. I got these cards from an older collector, so I know he didn't doctor them up or anything....I don't seem to be able to find anything about cards like these on the interweb....any assistance would be appreciated...