Registration requirement for suppliers requires registration when aggregate turnover exceeds prescribed threshold, including transfers and amalgamations. Suppliers are required to register under the Act when their aggregate turnover in a financial year exceeds the prescribed threshold, with a lower threshold for specified special category States. Persons registered or licensed under prior law on the day before the appointed day must register from the appointed day. Transferees or successors of businesses carried on as going concerns must register from the date of transfer, and transferees in sanctioned amalgamations must register from the date the Registrar of Companies issues the incorporation certificate. Aggregate turnover includes supplies made on behalf of principals; job worker supplies after job work are treated as supplies by the principal.