MSME classification change: composite investment-and-turnover criteria now govern category, triggering reclassification and reporting obligations. Revisions require use of a composite criterion of investment in plant and machinery or equipment and turnover to classify enterprises; aggregation applies to all units sharing a PAN by combining GSTIN-linked figures. Investment calculation is linked to prior Income Tax Returns, with self-declaration permitted for new enterprises until first ITR, excluding GST and specified exempt items; turnover excludes exports and must be linked to tax and GST data, with temporary self-declaration allowed for entities without PAN until a specified date. Transitional rules preserve existing status for defined post-change periods and the circular supersedes earlier guidance except delayed-payment provisions.