Glossary
Definitions of key terms used in reserve attestation reports. Each entry cites the relevant professional standard.
An engagement in which a practitioner issues a written communication expressing a conclusion about the reliability of a written assertion made by another party. The practitioner does not prepare the subject matter — they evaluate someone else's claim about it. Attestation is the umbrella category; examination, review, and agreed-upon procedures are the three types. Cite: AICPA AT-C Section 105, Concepts Common to All Attestation Engagements.
Standard: AT-C 105
The highest level of assurance available in U.S. attestation standards. The practitioner obtains sufficient appropriate evidence to express an opinion on whether the subject matter is presented in accordance with the applicable criteria, in all material respects. An examination opinion is an affirmative statement: 'In our opinion, management's assertion... is fairly stated, in all material respects.' This is the engagement type the GENIUS Act is expected to require for monthly reserve disclosures. Cite: AICPA AT-C Section 205, Examination Engagements.
Standard: AT-C 205
A limited assurance engagement. The practitioner performs inquiry and analytical procedures — substantially less than an examination — and expresses a conclusion in the negative form: 'Nothing came to our attention that caused us to believe the assertion is materially misstated.' A review provides less assurance than an examination but more than no assurance. Cite: AICPA AT-C Section 210, Review Engagements.
Standard: AT-C 210
An engagement in which the practitioner performs specific procedures agreed to by the engaging party and reports the factual findings without expressing an opinion or conclusion. The usefulness of AUP reports depends entirely on the scope of the agreed procedures. Two AUP reports with different scopes are not comparable. Cite: AICPA AT-C Section 215, Agreed-Upon Procedures Engagements.
Standard: AT-C 215
The international equivalent of U.S. attestation standards, issued by the International Auditing and Assurance Standards Board (IAASB). ISAE 3000 covers assurance engagements on subject matters other than historical financial information. It distinguishes between reasonable assurance (comparable to a U.S. examination) and limited assurance (comparable to a U.S. review). Non-U.S. issuers typically engage under ISAE 3000 rather than AT-C standards. Cite: IAASB ISAE 3000 (Revised), Assurance Engagements Other than Audits or Reviews of Historical Financial Information.
Standard: ISAE 3000 (Revised)
An audit of historical financial statements under Generally Accepted Auditing Standards (GAAS) or PCAOB standards. This is a distinct engagement type from an attestation. Some issuers disclose reserve information within audited financial statements rather than through a standalone attestation report. When this happens, the reserve data carries audit-level assurance, but the engagement scope, opinion scope, and applicable standards differ from a dedicated AT-C 205 examination. Cite: AICPA AU-C Sections; PCAOB Auditing Standards.
Standard: GAAS / PCAOB
Reserve disclosures published by the issuer without any independent practitioner engagement. No assurance is provided. The data reflects only the issuer's own assertion, unexamined.
Standard: N/A
Registration with the Public Company Accounting Oversight Board. PCAOB registration does not by itself mean the firm performs PCAOB-supervised work; it means the firm has submitted to PCAOB oversight. Post-GENIUS Act, PCAOB registration of the examining practitioner is expected to be a statutory requirement for permitted payment stablecoin issuers. Cite: PCAOB Rule 2100, Registration Requirements for Public Accounting Firms.
Standard: PCAOB Rule 2100
An opinion with no exceptions. The practitioner concluded that the subject matter is presented in accordance with the applicable criteria, in all material respects. Informally called a 'clean opinion.'
Standard: AT-C 205
An opinion with exceptions. The practitioner concluded that, except for the effects of the matter(s) described in the report, the subject matter is presented in accordance with the applicable criteria. A qualification identifies a specific deficiency.
Standard: AT-C 205
Stablecoin issuers and media outlets frequently describe reserve reports as 'audits.' In almost every case, the engagement is an attestation examination (AT-C 205) or a review (AT-C 210) — not an audit of financial statements. An audit examines financial statements in their entirety under GAAS or PCAOB standards. An attestation examination evaluates a specific assertion (e.g., 'reserves equal or exceed circulating supply as of this date'). The scopes are different, the standards are different, and the conclusions mean different things. Calling an attestation an 'audit' overstates the scope of the engagement and confuses the assurance level provided.
Standard: AT-C 105; AU-C 200
This registry is a personal project. It is informational only and does not constitute professional advice, an attestation, an opinion, or an assurance engagement. It is not affiliated with or endorsed by any employer or firm.