Restrictions on unlisted debt investments tighten mutual funds' exposure, mandating listed instruments, limits, and disclosure obligations. Revision tightens mutual fund investments in debt and money market instruments: unlisted debt is largely prohibited except defined exceptions, unlisted NCDs allowed only within capped percentages and subject to simple-structure, rating, security and monthly coupon requirements; timelines phase down exposure with grandfathering of existing holdings. Unrated non-government instruments face a net-assets exposure ceiling and board approvals. Structured obligations and credit-enhanced instruments have specified portfolio and group limits, equity-backed cover requirements, and mandatory distinctive disclosure. AMCs must maintain internal credit assessment systems with early warning mechanisms.