What is Customary Rights?

Legal Definition
Rights which are acquired by custom. They differ from prescriptive rights in this, that the former are local usages, belonging to all the inhabitants of a particular place or district - the latter are rights of individuals, independent of the place of their residence. Best on Pres. 79; Cruise, Dig. t. 31, c. 1, 7; 2 Greenl. Evi 542.
-- Bouviers Law Dictionary