Sub-account registration requirements add client undertakings, detailed annexure, fee obligation and recognition of exchange-traded derivatives. Amendments require FIIs seeking sub-account registration to submit detailed client information and affirmative undertakings via a new Annexure B to Form A, including client identity, constitution, custodian and bank details, and authorisations from the sponsoring FII; the sponsoring FII must affirm institutional status, broad based or proprietary character, registration and authority to invest and absence of specified regulatory or criminal disqualifications. The Board may grant registration upon receipt of these undertakings and payment of the prescribed registration fee. The regime expressly permits derivatives traded on recognised stock exchanges and clarifies exceptions for takeover-related sales.