A critical topic: in the digital world, possession is law. While traditional bank accounts have the bank as guarantor, on the Web the responsibility for custody falls entirely on the owner.
Disclaimer: This guide is for informational purposes only. Managing complex digital assets requires specific analysis integrating cybersecurity, tax law, and succession law expertise.
From a legal perspective, the MiCA Regulation and the 2024 succession reform clarify that the exclusive control power exercised through private keys defines asset ownership. There are two main custody modalities:
The holder retains private keys (e.g., Ledger, Trezor, MetaMask). Legally, this equates the wallet to a "private safe."
Keys are held by an intermediary (e.g., Exchange like Binance or Coinbase). Legally, the holder has a credit right against the intermediary.
Physical devices not connected to the internet.
Immune to remote hacker attacks.
Considered tangible movable property containing intangible property. In case of succession, physical possession of the device and "seed phrase" (12/24 recovery words) is the only way to transfer ownership.
Applications on smartphones or PCs.
Speed of use for frequent transactions.
Vulnerable to malware and phishing. Recommended only for small "cash register" amounts.
The Seed Phrase is the mnemonic representation of the private key. Whoever possesses it has total control of the assets.
A configuration that requires n signatures out of m total (e.g., 2 out of 3) to authorize a transaction.
2-of-3 Multi-Sig Example:
Key 1: Trustee (Lawyer/Fiduciary)
Key 2: Family Member
Key 3: Personal Backup
Ideal solution for businesses or complex inheritance planning.
The real challenge is not just "hiding" keys, but making them accessible to heirs in a legal and secure manner.
If the holder passes away without transmitting the keys, assets are technically "burned" (unrecoverable). However, legally, the value of those assets still contributes to the estate assets if the Tax Authority is aware of them (e.g., through fiscal monitoring - RW form).
As mentioned in the 2024 reform, the Trust allows you to:
Appoint a Trustee (a professional custodian) who holds or supervises the keys.
Guarantee asset segregation from potential creditors.
Plan the passage to beneficiaries without risks related to "manual" key delivery (which could be stolen or lost).
Ensure continuity of wallet custody even in case of incapacity.
Census all wallets and distinguish between custodial (exchange) and non-custodial. Document all addresses and access credentials.
Use hardware wallets for 90% of your assets. Reserve hot wallets only for small daily amounts.
Establish a procedure (e.g., through a notary or fiduciary) so
that heirs can find the keys without exposing them to third
parties during the holder's lifetime. Consider:
Safe Deposit Box
Digital Vault
Trustee
Ensure custody is consistent with tax returns (RW Form) to avoid penalties during succession. Crypto assets held abroad must be declared.
Get expert legal advice on cryptocurrency custody, succession planning, and MiCA compliance. Schedule a consultation to protect your digital assets.