The Kassen Kompany
The Kassen Kompany was originally formed by an adventuring group (consisting of Gagak, Caleb, Adaltrude, Owaddry, Diomedes, Continh - with a few NPCs holding a few shares in the company) in a game run by my first Pathfinder GM. I finished up running a few sessions, although with different characters, which helped develop some of the background material.
By the time the group broke up, Kassen Kompany owned a small fleet of merchant ships, a river barge service, an animal training centre, a library, and shares in a mine. We were also associated with a Military Training School, set up by Diomedes, and some cottages in Skids Landing owned by Gagak.
When the group split, many of the assets were hived off. The ships and barges still run under the Kassen Kompany name, run by some of the NPC members, and pay a regular dividend to the original shareholders. Gagak got the Animal Training Center as part of his share, while other assets went to compensate different shareholders.
The Kassen Kompany still exists as a barge and local shipping service, each of the original shareholders is financially secure, and even the minor shareholders have some sort of financial security. It was a good investment!