; and (B) the failure of an entity to satisfy the requirements of section 4(a), as described in section 4(c)(1)(A), shall be deemed to be a failure to satisfy the requirements of this section. 4. Attestation requirements (a) Attestation (1) In general Not later than 30 days after the effective date of this section, and monthly thereafter, each digital exchange and each digital custodian shall obtain from an independent auditing firm an attestation that the applicable entity has proof of reserves, which shall be accompanied by appropriate evidence demonstrating proof of those reserves, as described further in subsection (b). (2) Inability to obtain services of auditing firm (A) In general A digital exchange or digital custodian may contract with, or otherwise obtain the services of, a disinterested third party to carry out the responsibilities of an independent auditing firm under paragraph (1) only if the digital exchange or digital custodian is unable to contract with, or otherwise obtain the services of, an independent auditing firm to carry out those responsibilities. (B) Applicability If a digital exchange or digital custodian contracts with, or otherwise obtains the services of, a disinterested third party as described in subparagraph (A), that third party shall be subject to the requirements of this section to the same extent as an independent auditing firm carrying out the responsibilities described in paragraph (1). (3) Industry standard (A) Solicitation of standard Not later than 90 days after the date of enactment of this Act, the Public Company Accounting Oversight Board and the American Institute of Certified Public Accountants shall jointly issue a request for public comment soliciting proposals from the digital asset industry regarding a standard for the attestations required under this section. (B) Establishment of advisory committee After the expiration of the 90-day period described in subparagraph (A), the Public Company Accounting Oversight Board and the American Institute of Certified Public