participants, or any other class of customers. (ii) Customer choice A digital commodity exchange may not require a waiver from a customer described in subparagraph (A) as a condition of doing business on the exchange. (D) Blockchain service defined In this subparagraph, the term blockchain service means any activity relating to validating transactions on a blockchain system, providing security for a blockchain system, or other similar activity required for the ongoing operation of a blockchain system. (e) Market access requirements (1) In general A digital commodity exchange shall require any person who is not an eligible contract participant to access trading on the exchange through a digital commodity broker. (2) Affiliated commodity brokers A registered digital commodity exchange may permit an affiliated digital commodity broker to facilitate access to the digital commodity exchange. (3) Direct access for eligible contract participants Nothing in this section shall prohibit a digital commodity exchange in compliance with this section from permitting direct access for eligible contract participants. (4) Additional requirements The Commission may, by rule, impose any additional requirements related to the operations and activities of the digital commodity exchange and an affiliated digital commodity broker necessary to protect market participants, promote fair and equitable trading on the digital commodity exchange, and promote responsible economic or financial innovation. (f) Designation of chief compliance officer (1) In general A digital commodity exchange shall designate an individual to serve as a chief compliance officer. (2) Duties The chief compliance officer shall— (A) report directly to the board or to the senior officer of the exchange