Guys, explain me ownership pls

By example if I got a stone pickaxe, 50% owned by me and 30% by a friend 1 and 20% by a friend 2, I'll gain 50% of xp and they receiving 30% and 20% ?

If It's that, a man create a lot of tools and give them to their friends and they farm so the owner of the tools win all the xp ? That's why some people have c4 and bolt 1 day after wipe ? Is the ownership working like that ???