Copy rights basicaly relate to a written work or piece of art.
Trademark relates to a symbol or brand.
Patent refers to an items design.
I don't know if you meant patent or trademark. I am not sure they could patent the round, and if they did they almost certainly could not patent the chambering. Maybe I am wrong.
I guess they could trademark the cartridges name, although I don't know of this being done.
I am not a lawyer and maybe all of that is wrong. Someone will correct me if so
