Permitted investments define eligible securities and operational conditions for foreign portfolio investment, including delivery and dematerialisation requirements. Regulation 20 sets the permissible investment universe for foreign portfolio investors, including listed equity, mutual fund and CIS units, exchange traded derivatives, REITs/InvITs, IDRs and RBI permitted debt, and other Board specified instruments. It requires primarily delivery based secondary market transactions except enumerated exceptions, mandates dealing through Board registered stock brokers subject to listed exemptions, requires dematerialised holding with limited grandfathering, prescribes registration in the name of the beneficial owner unless approved otherwise, imposes an investment concentration limit with mandatory divestment and reclassification consequences for breaches, and subjects debt investment to RBI/Board directions.