Definition of large taxpayer links registered premises and income tax assessee status to special regulatory treatment. Definitions set the operative terms: the Act is the Central Excise Act, 1944; assessment includes self-assessment and provisional assessment; assessee includes those liable for duty, producers, manufacturers and registered private warehouse persons and their agents; Board denotes the constituted central board; duty is payable under the Act. The Tariff Act, notification and warehouse registration under rule 9 are defined, and other terms defer to the Act. A distinct definition of large taxpayer links registered premises and income tax assessee status with PAN subject to notified conditions.