ISIN allocation limits for debt securities establish issuance caps and mandatory semi annual reporting and disclosure obligations effective immediately. An ISIN allocation framework limits private placement ISINs to seventeen maturing per financial year plus twelve additional ISINs for section 54EC capital gains tax debt; within the seventeen, up to twelve ISINs are for plain vanilla debt and up to five for structured/market linked debt, with original maturity determining ISIN grouping for instruments with embedded options. Specified regulatory capital instruments are exempt. Issuers must amend their Articles of Association within six months and comply with detailed semi annual reporting to exchanges and depositories, which will upload and reconcile data and report violations to SEBI.