# Attestations, audits and proof of reserves answer different questions A financial-statement audit, an attestation over a specified reserve assertion and a proof-of-reserves exercise have different scopes. The label alone does not establish which assets, liabilities, controls or dates were examined. Proof of reserves must not be represented as a full audit or as a guarantee of solvency. Evidence: [Investor advisory on proof-of-reserve reports](https://pcaobus.org/resources/information-for-investors/investor-advisories/investor-advisory-exercise-caution-with-third-party-verification-proof-of-reserve-reports); [USDC and EURC transparency](https://www.circle.com/transparency) Canonical: https://degreesofsatoshi.com/encyclopedia/attestations-audits-proof-of-reserves/ Published: 2026-10-02 Substantively modified: 2026-10-02 Independently verified by an automated reviewer: 2026-10-02T18:26:58.075Z Data current through: 2026-10-02 AI-assisted research and drafting with a separate automated source-verification pass; no external expert or named human review is implied. ## Key facts - **Scope first:** Identify the assertion and criteria actually examined. ([USDC and EURC transparency](https://www.circle.com/transparency); [Investor advisory on proof-of-reserve reports](https://pcaobus.org/resources/information-for-investors/investor-advisories/investor-advisory-exercise-caution-with-third-party-verification-proof-of-reserve-reports)) - **Point-in-time limit:** A snapshot does not show what happens to assets afterward. ([Investor advisory on proof-of-reserve reports](https://pcaobus.org/resources/information-for-investors/investor-advisories/investor-advisory-exercise-caution-with-third-party-verification-proof-of-reserve-reports)) - **No equivalence:** PCAOB’s investor advocate cautions that proof-of-reserve reports are not audits. ([Investor advisory on proof-of-reserve reports](https://pcaobus.org/resources/information-for-investors/investor-advisories/investor-advisory-exercise-caution-with-third-party-verification-proof-of-reserve-reports)) ## Translate the label into a question Ask, “What exactly did this engagement test?” A reserve assertion might compare assets and token circulation on named dates. A broader financial-statement audit addresses a different body of information. A proof-of-reserves exercise can range from published wallet evidence to a service provider performing selected procedures. For any report, identify the preparer, independent practitioner if present, criteria, subject matter, dates, conclusion and exclusions. This is more informative than promoting “audited” or dismissing “attested” without reading the underlying work. Different engagements can be useful for different questions. Evidence: [USDC and EURC transparency](https://www.circle.com/transparency); [Investor advisory on proof-of-reserve reports](https://pcaobus.org/resources/information-for-investors/investor-advisories/investor-advisory-exercise-caution-with-third-party-verification-proof-of-reserve-reports) ## Asset existence is only one part of solvency A wallet can visibly hold an asset while obligations remain elsewhere. In an illustrative example, a custodian shows $100 million in assets and reports $80 million of customer balances. If another $30 million liability is outside the exercise, the displayed $20 million surplus does not describe the complete position. This example is arithmetic, not an allegation about a named business. Its point is to ask whether the liabilities population is complete, assets are controlled and unencumbered, and the claims being compared belong to the same entity and date. A token ledger cannot independently answer every off-chain question. Evidence: [Investor advisory on proof-of-reserve reports](https://pcaobus.org/resources/information-for-investors/investor-advisories/investor-advisory-exercise-caution-with-third-party-verification-proof-of-reserve-reports) ## Use a short evidence checklist before accepting an assurance label Identify who made the assertion, who examined it, the reporting date, the assets and liabilities included, and the conclusion actually expressed. A report about reserves at one date does not establish every later balance or every operational control. Paxos provides a concrete distinction: its portfolio composition reports released promptly after month-end are self-reported and described as not independently reviewed, while independent examination documents are separate. Preserve those labels when citing the evidence instead of calling every reserve document an audit. Evidence: [PayPal USD Transparency](https://www.paxos.com/pyusd-transparency) ## Questions ### Can an attestation be useful? Yes, when its subject matter, criteria, dates and conclusion answer the question being asked. It should be described within that scope. Evidence: [USDC and EURC transparency](https://www.circle.com/transparency); [Investor advisory on proof-of-reserve reports](https://pcaobus.org/resources/information-for-investors/investor-advisories/investor-advisory-exercise-caution-with-third-party-verification-proof-of-reserve-reports) ### Does proof of reserves prove solvency? Not on its own. Asset evidence may omit liabilities, restrictions and other conditions needed to assess whether obligations can be met. Evidence: [Investor advisory on proof-of-reserve reports](https://pcaobus.org/resources/information-for-investors/investor-advisories/investor-advisory-exercise-caution-with-third-party-verification-proof-of-reserve-reports) ## Claims and scope ### attestations-audits-proof-of-reserves-quick-answer A financial-statement audit, an attestation over a specified reserve assertion and a proof-of-reserves exercise have different scopes. The label alone does not establish which assets, liabilities, controls or dates were examined. Proof of reserves must not be represented as a full audit or as a guarantee of solvency. Scope: {"collection":"stablecoins","dataAsOf":"2026-10-02","blockHeight":null} ### attestations-audits-proof-of-reserves-fact-scope-first Scope first: Identify the assertion and criteria actually examined. Scope: {"collection":"stablecoins","dataAsOf":"2026-10-02","blockHeight":null} ### attestations-audits-proof-of-reserves-fact-point-in-time-limit Point-in-time limit: A snapshot does not show what happens to assets afterward. Scope: {"collection":"stablecoins","dataAsOf":"2026-10-02","blockHeight":null} ### attestations-audits-proof-of-reserves-fact-no-equivalence No equivalence: PCAOB’s investor advocate cautions that proof-of-reserve reports are not audits. Scope: {"collection":"stablecoins","dataAsOf":"2026-10-02","blockHeight":null} ## Sources - [Investor advisory on proof-of-reserve reports](https://pcaobus.org/resources/information-for-investors/investor-advisories/investor-advisory-exercise-caution-with-third-party-verification-proof-of-reserve-reports) — PCAOB Office of the Investor Advocate. Proof of reserves is not an audit; obligations and rights may be omitted. Locator: PoR Reports Are Not Audits; Limitations. Retrieved: 2026-10-02T14:41:32.877368+00:00. - [USDC and EURC transparency](https://www.circle.com/transparency) — Circle. Reserve categories, dated third-party reports, distinction between circulation and assets. Locator: Balances; Monthly assurance and transparency. Retrieved: 2026-10-02T14:38:29.678364+00:00. - [PayPal USD Transparency](https://www.paxos.com/pyusd-transparency) — Paxos. PYUSD issuer disclosures and dated reserve attestations. Locator: Reserve reports; Issuer disclosures. Retrieved: 2026-10-02T17:03:43.402Z. ## Revision history - 2026-10-02: First publication after primary-source research and independent automated verification. - 2026-10-02: Expanded explanation: Use a short evidence checklist before accepting an assurance label. Worked examples are illustrative; source checks and independent verification are recorded separately. ## Cite this entry Degrees of Satoshi editorial project. “Attestations, audits and proof of reserves answer different questions.” Published 2026-10-02; updated 2026-10-02. https://degreesofsatoshi.com/encyclopedia/attestations-audits-proof-of-reserves/