I would just like to add that those blue backed Old Mill reprints were made over 20 years ago. The guy who has this Cobb says he's had the reprint for 25 years.
There's no factory number on the Cobb either.
http://www.ebay.com/itm/1909-1911-T-...item337b105e20
HOWEVER, there IS a factory number on this
Cy Young Blue Old Mill reprint. Reprint on the left, authentic on the right. The cards also seem to have the same darker than usual font on the front.
