Registration requirement for excisable goods: mandates registration for producers, traders, warehouses and certain importers unless exempted. Rule 9 requires registration for persons producing, manufacturing, trading in, holding private store rooms or warehouses for, or otherwise using excisable goods, and for importers issuing invoices enabling CENVAT credit; prior registrations under rule 9 of the Central Excise Rules, 2002 are deemed valid, while the Board may exempt classes of persons and prescribe registration conditions, safeguards and procedure by notification.