My grandfather had a self earned shop and house.
My grandfather has 2 sons, my father and his elder brother.
Around 20-25 years back, my father having a job refused his share in the shop and wrote the same in a stamp paper that he doesn't want any share from the shop.
(For clarity:He didn't mention that he has got his share)
Can my father/me claim our share in the shop now? My uncle has also changed the name of the shop.