I don't know if this is limited to the Anson card, this is where i have observed it, but some appear to have no writing on the back under the Goodwin & Co., for example:
http://www.ebay.com/itm/1888-N162-Go...item20c8f07aa7
While others have additional writing that I can't quite read, for example:
http://cgi.ebay.com/ws/eBayISAPI.dll...vip=true&rt=nc
Does anyone know the story here? Thanks.