{"release":{"id":"2d86bd12ba77a288053b34ea2517324b92d03c8039b7f5d156fa4002421384a1","published":"2026-11-10T16:06:46Z","pinned":false},"limits":{"coverage":{"history":"full","held_since":"2023-06-09","gaps":[],"covered":["MiCA L1"],"not_covered":["national guidance","court decisions"]},"freshness":{"release_id":"2d86bd12ba77a288053b34ea2517324b92d03c8039b7f5d156fa4002421384a1","release_published":"2026-11-10T16:06:46Z","checked_at":"2026-11-09","checked_against":"EUR-Lex"},"truncation":null,"failures":[],"incomplete":[]},"page":{"path":"/mica/articles/66","url":"https://www.headlesslaw.com/mica/articles/66","title":"Article 66 — Obligation to act honestly, fairly and professionally in the best interests of clients","family":"l1_hand","work_id":"mica","status":"in_force","force_status":"in_force","date_state":"current","requested_date":null,"as_of":"2026-11-11","applies_from":"2024-12-30","application":{"state":"applicable","next":null,"dates":[{"at":"2023-06-29","note":"Article 149(4)"},{"at":"2024-12-30","note":"Article 149(2)"}]},"version_label":"Consolidated version of 9 January 2024","check":{"against":"EUR-Lex","on":"2026-11-09"},"check_result":"matched","official_url":"https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:02023R1114-20240109","valid_from":"2024-01-09","valid_until":null,"revision":1,"content_id":"d5dadc56eeb1a64f","change_date":null,"nearest_versions":["2023-06-09","2024-01-09"],"first_text_date":"2023-05-31","correction_applies":false,"versions":["2023-06-09","2024-01-09"],"version_url":"https://www.headlesslaw.com/mica/articles/66/versions/2024-01-09","revision_url":"https://www.headlesslaw.com/mica/articles/66/versions/2024-01-09/rev/d5dadc56eeb1a64f","versions_url":"https://www.headlesslaw.com/mica/articles/66/versions","relations_url":"https://www.headlesslaw.com/mica/articles/66/relations","source_line":null,"attribution":null},"provenance":{"official_url":"https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:02023R1114-20240109","check":{"result":"matched","checked_at":"2026-11-09","against":"EUR-Lex"},"repo_path":null,"body_sha256":"87e444badba09bfef382978a47b1d5305d976a11f4b746f11d797a89b7d6a331","markdown_sha256":"d20250f6716e9515ca0a91a8fb2decccbbaf1387ba68c3a5dfc8a1a518c74b73"},"units":[{"locator":"mica/art/66","kind":"article","status":"in_force","label":null,"heading":"Obligation to act honestly, fairly and professionally in the best interests of clients","text":"","marks":[],"revision":1,"text_hash":"e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855","reason":null},{"locator":"mica/art/66/para/1","kind":"paragraph","status":"in_force","label":"1.","heading":null,"text":"Crypto-asset service providers shall act honestly, fairly and professionally in accordance with the best interests of their clients and prospective clients.","marks":[],"revision":1,"text_hash":"12cbb3a6e8bcb3da7583c9b6a42548f74976b68df927ca3019e861922061eec6","reason":null},{"locator":"mica/art/66/para/2","kind":"paragraph","status":"in_force","label":"2.","heading":null,"text":"Crypto-asset service providers shall provide their clients with information that is fair, clear and not misleading, including in marketing communications, which shall be identified as such. Crypto-asset service providers shall not, deliberately or negligently, mislead a client in relation to the real or perceived advantages of any crypto-assets.","marks":[],"revision":1,"text_hash":"21a0490f63af8df7e776b0ed371ff82699ef1b92028c2789a327ac7ee3f6f127","reason":null},{"locator":"mica/art/66/para/3","kind":"paragraph","status":"in_force","label":"3.","heading":null,"text":"Crypto-asset service providers shall warn clients of the risks associated with transactions in crypto-assets.","marks":[],"revision":1,"text_hash":"f8da11c8e0b6807c47afee14f5a86918fa13a0e2637ea8862b6dd48f5e2c500d","reason":null},{"locator":"mica/art/66/para/3/cont/1","kind":"continuation","status":"in_force","label":null,"heading":null,"text":"When operating a trading platform for crypto-assets, exchanging crypto-assets for funds or other crypto-assets, providing advice on crypto-assets or providing portfolio management on crypto-assets, crypto-asset service providers shall provide their clients with hyperlinks to any crypto-asset white papers for the crypto-assets in relation to which they are providing those services.","marks":[],"revision":1,"text_hash":"a4da81a4c35007d0be51f62676d4c6c6a5db49725aa5564eb1d31437ecf0ed55","reason":null},{"locator":"mica/art/66/para/4","kind":"paragraph","status":"in_force","label":"4.","heading":null,"text":"Crypto-asset service providers shall make their policies on pricing, costs and fees publicly available, in a prominent place on their website.","marks":[],"revision":1,"text_hash":"fc25e9a20bef2d15f5bcaf8317067f1e0363aa92c48b2e5c087671399e8224c7","reason":null},{"locator":"mica/art/66/para/5","kind":"paragraph","status":"in_force","label":"5.","heading":null,"text":"Crypto-asset service providers shall make publicly available, in a prominent place on their website, information related to the principal adverse impacts on the climate and other environment-related adverse impacts of the consensus mechanism used to issue each crypto-asset in relation to which they provide services. That information may be obtained from the crypto-asset white papers.","marks":[],"revision":1,"text_hash":"53aef4c728d02e0156426134a46098ee2229e0e33ae24523700ba008a3ac9a76","reason":null},{"locator":"mica/art/66/para/6","kind":"paragraph","status":"in_force","label":"6.","heading":null,"text":"ESMA, in cooperation with EBA, shall develop draft regulatory technical standards on the content, methodologies and presentation of information referred to in paragraph 5 in respect of the sustainability indicators in relation to adverse impacts on the climate and other environment‐related adverse impacts.","marks":[],"revision":1,"text_hash":"a81c38dfeb890722f65c4676103dabed38dc552453d033e2dece1bb988698aea","reason":null},{"locator":"mica/art/66/para/6/cont/1","kind":"continuation","status":"in_force","label":null,"heading":null,"text":"When developing the draft regulatory technical standards referred to in the first subparagraph, ESMA shall consider the various types of consensus mechanisms used to validate crypto-asset transactions, their incentive structures and the use of energy, renewable energy and natural resources, the production of waste and greenhouse gas emissions. ESMA shall update the regulatory technical standards in the light of regulatory and technological developments.","marks":[],"revision":1,"text_hash":"9ad1cfb3db8f79e0dfca9a50c21c2791a69c3241f53ec3a1a67dc36e19d91416","reason":null},{"locator":"mica/art/66/para/6/cont/2","kind":"continuation","status":"in_force","label":null,"heading":null,"text":"ESMA shall submit the draft regulatory technical standards referred to in the first subparagraph to the Commission by 30 June 2024.","marks":[],"revision":1,"text_hash":"68b976bc5a2accfd859cd79c0853a58f637d640a933b988d93355e7acc9f136f","reason":null},{"locator":"mica/art/66/para/6/cont/3","kind":"continuation","status":"in_force","label":null,"heading":null,"text":"Power is delegated to the Commission to supplement this Regulation by adopting the regulatory technical standards referred to in the first subparagraph of this paragraph in accordance with Articles 10 to 14 of Regulation (EU) No 1095/2010.","marks":[],"revision":1,"text_hash":"6b77dab89a34da6ab8ea8ce7f5ee5cf35c48e3641fbb59d7fd6722d334e1d95a","reason":null}],"markdown":"*In force · Consolidated version of 9 January 2024 · Verified 9 Nov 2026 · [Official source](https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:02023R1114-20240109)*\n\n1. <a id=\"p-1\"></a>[Crypto-asset service providers](https://www.headlesslaw.com/definitions/mica/crypto-asset-service-provider) shall act honestly, fairly and professionally in accordance with the best interests of their [clients](https://www.headlesslaw.com/definitions/mica/client) and prospective clients.\n2. <a id=\"p-2\"></a>[Crypto-asset service providers](https://www.headlesslaw.com/definitions/mica/crypto-asset-service-provider) shall provide their [clients](https://www.headlesslaw.com/definitions/mica/client) with information that is fair, clear and not misleading, including in marketing communications, which shall be identified as such. [Crypto-asset service providers](https://www.headlesslaw.com/definitions/mica/crypto-asset-service-provider) shall not, deliberately or negligently, mislead a client in relation to the real or perceived advantages of any crypto-assets.\n3. <a id=\"p-3\"></a>[Crypto-asset service providers](https://www.headlesslaw.com/definitions/mica/crypto-asset-service-provider) shall warn clients of the risks associated with transactions in crypto-assets.\n\n    When operating a trading platform for [crypto-assets](https://www.headlesslaw.com/definitions/mica/crypto-asset), exchanging crypto-assets for [funds](https://www.headlesslaw.com/definitions/mica/funds) or other crypto-assets, [providing advice on crypto-assets](https://www.headlesslaw.com/definitions/mica/providing-advice-on-crypto-assets) or providing portfolio management on crypto-assets, [crypto-asset service providers](https://www.headlesslaw.com/definitions/mica/crypto-asset-service-provider) shall provide their clients with hyperlinks to any crypto-asset white papers for the crypto-assets in relation to which they are providing those services.\n4. <a id=\"p-4\"></a>[Crypto-asset service providers](https://www.headlesslaw.com/definitions/mica/crypto-asset-service-provider) shall make their policies on pricing, costs and fees publicly available, in a prominent place on their website.\n5. <a id=\"p-5\"></a>[Crypto-asset service providers](https://www.headlesslaw.com/definitions/mica/crypto-asset-service-provider) shall make publicly available, in a prominent place on their website, information related to the principal adverse impacts on the climate and other environment-related adverse impacts of the [consensus mechanism](https://www.headlesslaw.com/definitions/mica/consensus-mechanism) used to issue each crypto-asset in relation to which they provide services. That information may be obtained from the crypto-asset white papers.\n6. <a id=\"p-6\"></a>ESMA, in cooperation with EBA, shall develop draft regulatory technical standards on the content, methodologies and presentation of information referred to in paragraph 5 in respect of the sustainability indicators in relation to adverse impacts on the climate and other environment‐related adverse impacts.\n\n    When developing the draft regulatory technical standards referred to in the first subparagraph, ESMA shall consider the various types of [consensus mechanisms](https://www.headlesslaw.com/definitions/mica/consensus-mechanism) used to validate [crypto-asset](https://www.headlesslaw.com/definitions/mica/crypto-asset) transactions, their incentive structures and the use of energy, renewable energy and natural resources, the production of waste and greenhouse gas emissions. ESMA shall update the regulatory technical standards in the light of regulatory and technological developments.\n\n    ESMA shall submit the draft regulatory technical standards referred to in the first subparagraph to the Commission by 30 June 2024.\n\n    Power is delegated to the Commission to supplement this Regulation by adopting the regulatory technical standards referred to in the first subparagraph of this paragraph in accordance with Articles 10 to 14 of Regulation (EU) No 1095/2010.\n\n***\n\n### Related\n\n* [providing advice on crypto-assets](https://www.headlesslaw.com/definitions/mica/providing-advice-on-crypto-assets) — definition used in this article\n* [crypto-asset service](https://www.headlesslaw.com/definitions/mica/crypto-asset-service) — definition used in this article\n* [consensus mechanism](https://www.headlesslaw.com/definitions/mica/consensus-mechanism) — definition used in this article\n* [crypto-asset](https://www.headlesslaw.com/definitions/mica/crypto-asset) — definition used in this article\n* [client](https://www.headlesslaw.com/definitions/mica/client) — definition used in this article\n* [funds](https://www.headlesslaw.com/definitions/mica/funds) — definition used in this article\n\n## Related Level 2 and Level 3\n\n### Binding measures\n\n- [2025/422 — RTS — Sustainability Indicators \\[in force\\]](../level-2/rts/regulatory-technical-standards-sustainability-indicators-adverse-climate-environment-impacts.md)\n\n### Guidance and Q&A\n\n- [ESMA Q&A 2552 — Q&A — Application of Title II requirements to CASPs \\[Published Answer Updated\\]](../level-3/q-and-a/esma/esma-qa-2552-application-title-ii-requirements-casps-operating-trading.md)\n- [ESMA Q&A 2607 — Q&A — Staking on own account \\[Answer Published\\]](../level-3/q-and-a/esma/esma-qa-2607-staking-own-account.md)\n- [ESMA Q&A 2883 — Q&A — Crypto-asset lending services under MiCA \\[Answer Published\\]](../level-3/q-and-a/esma/esma-qa-2883-crypto-asset-lending-services.md)\n- [ESMA75-113276571-1742 — Opinion — Non-MiCA-compliant ARTs and EMTs \\[published\\]](../level-3/opinions/esma75-113276571-1742-opinion-on-non-mica-compliant-arts-and-emts.md)\n\n### Process documents\n\n- [ESMA75-453128700-1229 — Report — Second Technical Standards Package \\[final draft submitted\\]](../process/final-report-on-the-technical-standards-specifying-certain-requirements-of-mica-2nd-package.md)\n\n***\n\n[Title V — Authorisation and operating conditions for crypto-asset service providers](../titles/v.md) › Chapter 2 — Obligations for all crypto-asset service providers · [← Article 65](65.md) · [Article 67 →](67.md)\n"}