Piedmont T206 with date stamped on back...

[scottglevy]

Welcome to the board. I'm certainly not the most knowledgeable on T206s .. but I do know a bit.

This series was issued from 1909 to 1911.

Your stamp was almost certainly put there by a collector (quite likely the original collector). It was not factory issued. I have seen other time stamps - or more commonly name stamps from collectors on the back of T206s.

Having said that, some collectors actually like the nostalgia of a time-period stamp on the back of a tobacco card, so don't feel too badly about it.

I've heard rumors that cards were used as package stiffeners. But I also know for a fact that several companies considered them to be important marketing premiums - several ads from tobacco companies during that period explicitly advertise that ballplayers come in their cigarette packs (HINDU ads come to mind most readily).

Enjoy the card - it's from my favorite hobby set!

Best Regards,
Scott