# Reserve attestation

An independent accountant's opinion on an issuer's reserve figures at specific dates; standards and frequency differ by issuer and law.

Canonical: https://achivx.org/glossary/reserve-attestation/
Updated: 2026-11-01

A reserve attestation is a report by an independent accountant giving an opinion on an issuer's statement about its reserves at stated dates. Circle's USDC report is an examination under AICPA attestation standards; Tether's is a reasonable assurance report under ISAE 3000R by BDO. The GENIUS Act requires a registered public accounting firm to examine the issuer's monthly reserve report each month. MiCA instead requires asset-referenced token issuers to mandate an independent audit of the reserve every six months.

## What the sources say

| Source | Quote | Link |
|---|---|---|
| Circle USDC examination report, September 2026 | "Our examination was conducted in accordance with attestation standards established by the American Institute of Certified Public Accountants (AICPA)." | [6778953.fs1.hubspotusercontent-na1.net](https://6778953.fs1.hubspotusercontent-na1.net/hubfs/6778953/USDCAttestationReports/2026/2026%20USDC_Examination%20Report%20September%2026.pdf) |
| Tether ISAE 3000R assurance report by BDO, as at 30 September 2026 | "We have been engaged by Tether Global Investments Fund SICAF SA to perform a reasonable assurance engagement on the Financials Figures and Reserves Report of Tether International, S.A. de C.V." | [assets.ctfassets.net](https://assets.ctfassets.net/vyse88cgwfbl/7nQYtcoP9GxIUFSyro2dGK/8d0521470b9e99c8c0831019cabea4ee/ISAE_3000R_-_Opinion_Tether_International_Financial_Figure_30-09-2026.pdf) |
| GENIUS Act, sec. 4(a)(3): monthly examination | "A permitted payment stablecoin issuer shall, each month, have the information disclosed in the previous month-end report required under paragraph (1)(D) examined by a registered public accounting firm." | [govinfo.gov](https://www.govinfo.gov/content/pkg/PLAW-119publ27/html/PLAW-119publ27.htm) |
| MiCA Art 36(9): six-monthly independent audit of the reserve (ARTs) | "issuers of asset-referenced tokens shall mandate an independent audit of the reserve of assets every six months" | [publications.europa.eu](https://publications.europa.eu/resource/cellar/01d55833-0660-11ee-b12e-01aa75ed71a1.0006.03/DOC_1) |

## Where the sources differ

The sources set different rules. The GENIUS Act requires a monthly examination by a registered public accounting firm. MiCA requires an independent audit every six months for asset-referenced tokens. Issuers' reports use different standards (AICPA examination, ISAE 3000R).

## Related terms

- [Reserve / reserve assets](/glossary/reserve-assets/)
- [Proof of reserves](/glossary/proof-of-reserves/)
- [Fiat-backed stablecoin](/glossary/fiat-backed-stablecoin/)
- [Issuer](/glossary/issuer/)

## See also

- Explainer: [What is a reserve attestation — and why is it not an audit?](https://achivx.com/academy/issuers/what-is-a-reserve-attestation.html)
- Review: [revain.org/coins/usdc/](https://revain.org/coins/usdc/)
- Review: [revain.org/coins/usde/](https://revain.org/coins/usde/)
- Review: [revain.org/coins/usdtb/](https://revain.org/coins/usdtb/)

Checked against the sources on 2026-11-01.

## revain.org
- https://revain.org/coins/usdc/
- https://revain.org/coins/usde/
- https://revain.org/coins/usdtb/

## Sources
- https://6778953.fs1.hubspotusercontent-na1.net/hubfs/6778953/USDCAttestationReports/2026/2026%20USDC_Examination%20Report%20September%2026.pdf
- https://assets.ctfassets.net/vyse88cgwfbl/7nQYtcoP9GxIUFSyro2dGK/8d0521470b9e99c8c0831019cabea4ee/ISAE_3000R_-_Opinion_Tether_International_Financial_Figure_30-09-2026.pdf
- https://www.govinfo.gov/content/pkg/PLAW-119publ27/html/PLAW-119publ27.htm
- https://publications.europa.eu/resource/cellar/01d55833-0660-11ee-b12e-01aa75ed71a1.0006.03/DOC_1