Section 5(13) in Bureau of Indian Standards (Hallmarking) Regulations, 2018
(13)The registered jeweller shall maintain record of copies of request for hallmarking, invoice or bill issued by assaying and hallmarking centre, invoice or bill of sale of hallmarked articles and invoice or bill of purchase of hallmarked articles from jewellers, if any, for a period of five years or till the hallmarked articles are sold, whichever is longer.
