Registration requirement for service providers triggers when taxable receipts exceed the prescribed threshold; file registration within thirty days. Registration requires application to the jurisdictional Superintendent of Central Excise in the prescribed form: input service distributors must apply within thirty days of commencing business or of the specified reference date; providers of taxable services must apply within thirty days of exceeding the prescribed aggregate taxable service threshold in a financial year. Procedural provisions of sub rules (2) to (8) of rule 4 of the Service Tax Rules, 1994 apply to such applicants, subject to Board prescribed modifications.