Now that this auction is over, I feel safe with posting this...
http://www.ebay.com/itm/321384737738...84.m1423.l2649
Seller claims that the autograph on the card is not authentic. I own 9 Greenberg autographs, but I don't think this is a fake, although I never have seen a fake...
I emailed the seller and received this note:
"While we do not have a formal evaluation, someone very familiar with a three-letter company that specializes in authenticating signatures told us it was not a genuine Greenberg auto."
Just wanted to get thoughts on this auto.