MiCA and Crypto Treasury Custody: Self-Custody vs the CASP Line

The first MiCA-custody question a treasury asks is usually the wrong one. It is not "how do we comply with the custody rules" — it is "do the custody rules even apply to us?" Self-custodying your own treasury and custodying crypto for clients are different sides of a line. This guide is that line.

TL;DR

• MiCA custody-and-administration obligations bind a CASP custodying on behalf of clients — safekeeping assets / means of access (keys) / control for clients.
• A company self-custodying its own treasury is generally on the other side of that line (not a client-custody service) — fact-specific, counsel-confirmed.
• CASP custody duties: segregate client assets (physically + legally, separate DLT storage), individual position register, custody policy + agreement, ≥ quarterly statements.
• Custody is an authorised CASP class with own-funds/insurance set by its authorisation (tier-dependent — not one universal figure).
• Transitional: CASP authorisation from early 2025; member-state grandfathering up to ~18 months (broadly to mid-2026) — jurisdiction-specific.
• MiCA governs the custody service; it does not replace the treasury's own accounting/reconciliation.

The question that comes first

MiCA is Regulation (EU) 2023/1114. Its custody and administration of crypto-assets on behalf of clients means safekeeping crypto-assets, or the means of access (private keys), or exercising control over them — for clients. The decisive treasury question is therefore scope:

• self-custodying your own treasury → holding your own assets, generally not a client-custody service;
• holding/controlling crypto for third parties → potentially a CASP custody service.

Treating an internal treasury as if it triggered full CASP client-asset rules over-applies the regime; missing that your structure does hold for others under-applies it. Characterisation first, with counsel — before any operational design.

What a CASP custodian must do

If the activity is a CASP custody service, MiCA requires (among other things):

The own-funds requirement is class-dependent — do not assume a single universal figure; it follows the CASP's authorisation tier.

The transitional timing

MiCA's CASP regime applies with member-state transitional arrangements: CASP authorisation processes from early 2025, with a grandfathering period of up to ~18 months for existing providers depending on the member state (broadly up to around mid-2026). Exact dates are member-state-specific (consistent with the French PSAN→CASP transition and the MiCA stablecoin timeline). If your activity is or becomes a CASP custody service, the authorisation and window are jurisdiction-specific and counsel-confirmed.

Custody arrangement vs accounting

Whether self-custodied or with a regulated custodian, the treasury still accounts:

• self-custody → existence evidence is key control;
• third-party custody → existence evidence is the custody relationship + confirmations (see auditing crypto existence).

MiCA governs the custody service; it does not replace the treasury's own classify / value / reconcile / audit-trail obligations (see multisig treasury reconciliation).

Practical guidance

1. Characterise first — self-custody of own treasury vs custody for clients — with counsel.
2. Do not over-apply CASP client-asset rules to an internal treasury.
3. If a CASP custody service, design for segregation, the position register, policy/agreement, statements.
4. Treat own-funds as class-dependent — confirm the figure for your authorisation.
5. Track the member-state transitional window if authorisation applies.
6. Account and reconcile regardless — MiCA custody ≠ treasury accounting.

How vendor tools relate to MiCA custody

Cryptio and Bitwave sit on the accounting/reconciliation layer — relevant whether the treasury is self-custodied or with a CASP. Confirm the tool keeps a per-account/position register and audit trail that supports either custody model — it is the accounting evidence, not the MiCA authorisation itself.

How Wag3s helps

Wag3s Ledger maintains the per-position register, reconciliation, and audit trail a treasury needs independently of whether it self-custodies or uses a regulated custodian — supporting the accounting side while the MiCA custody characterisation stays a counsel-confirmed legal question. See the Ledger product page and the Wag3s for accountants page.

Further reading

• Safe Treasury Setup Best Practices
• Multisig Treasury Reconciliation (Safe)
• Auditing Crypto Existence and Ownership
• MiCA Stablecoins (ART/EMT)
• Crypto Audit Trail and Piste d'Audit Fiable
• DAO Treasury

Sources

• MiCA — Regulation (EU) 2023/1114: custody and administration of crypto-assets on behalf of clients = safekeeping assets / means of access (private keys) / control for clients
• CASP custody obligations: physical + legal client-asset segregation (incl. separate DLT storage), individual position register (operations recorded without undue delay), custody policy + client agreement, position statements at least quarterly and on request; custody is an authorised CASP service with class-dependent own-funds/insurance
• MiCA CASP transitional arrangements (authorisation from early 2025; member-state grandfathering up to ~18 months, broadly to mid-2026) — jurisdiction-specific; self-custody of own treasury vs client-custody service is a fact-specific, counsel-confirmed distinction