Littleton profit shares

Hi everyone, I'm new to this sub but I'm going to keep my story short and sweet. I'm 20 and got into coin collecting with my grandfather who has sadly passed away. He left me with a bunch of coins (including a 1909 s.v.d.b.!) and along with it, a few (won't give the number for security reasons) of Littleton profit shares. This was in the collection, however, I can't find much on it. Any advice on what it's worth/ what it means/ what it is used for? Anything will be useful. Thanks friends :)