Cancellation of registration: officers may cancel registrations and require payment for input tax credit or output tax on held goods. The proper officer may cancel registration on specified grounds including business discontinuance, change in constitution, cessation of liability, prescribed contraventions, prolonged non filing, non commencement after voluntary registration, or fraud, with an opportunity to be heard. Cancellation may be retrospective, does not affect liabilities for prior periods, is deemed where Central Act cancellation occurs, and requires the registrant to pay an amount equivalent to input tax credit or output tax on goods, with prescribed calculations and reductions for capital goods.