One of the more storied franchises of the early days of the National Football League was the Pottsville Maroons. The Maroons by all rights claimed the 1925 NFL title but were controversially suspended by the league, thus giving the Chicago Cardinals the official title.
Fast-forward a few seasons and the Maroons limped to a 2-8 finish in 1928. They were then sold to a New England-based partnership and moved to Boston. The newly christened Boston Bulldogs lasted just one season before folding, but not before issuing public stock certificates. Here is a picture of one such certificate:
After the demise of the Bulldogs there were additional attempts to establish pro football in the Boston area. None succeeded until the formation of the Boston Patriots of the AFL in 1960.