Can I sell ancestral property without telling my relatives

i am inheritor of ancestral property (location- Dwarahat, Almora, Uttarakhand)of my late Grandfather. Khatauni has details of all inheritors including me. All 4 sons of my grandfather r not alive. we r 12 grandsons (6+3+1+2). the property consists of different plots scattered in different place within same Tehsil. My share in property is 12.5%. Family partition was mutually done by 4 sons & allocation was made but partition was not registered. one cousin whose share is 4.2% started selling (without consent of others) land at prime locality citing the reason that it is within his share. He sold 2 pieces of land assigned to my father in family partition. i objected to the mutation but nothing happened, as Tehsildar informed that any shareholder can sell land without calling for no objection from other shareholders as long the land sold is within his share. whether it is legal and how can i protect my share of land from further sale? can not i register my share of plots in my own name?