GST regularization clarifies exemptions and subsidy treatment for rail services, SPV infrastructure, RERA, payments, reinsurance, accommodation. Clarification and regularization of GST liabilities and exemptions for specified services: Ministry of Railways public services and inter-zone supplies exempted and regularized on an as is where is basis; SPV supplies of infrastructure use exempted and regularized for the stated historical period; RERA statutory collections fall under the governmental authority exemption; incentive sharing by acquiring banks under the notified RuPay/UPI scheme treated as a subsidy and not taxable where distributed in NPCI-determined proportions; reinsurance of certain exempt insurance schemes and government-premium schemes regularized for past periods and reinsurance is clarified to include retrocession.