Wallet Portability and Migration

Tatum Smart Wallet provides a planned exit path that lets you reconstruct and move a wallet’s underlying private key outside Tatum’s MPC infrastructure.

Overview

Tatum Smart Wallet normally uses multiparty computation (MPC), a signing model in which parties collaborate to authorize a transaction without reconstructing the complete private key. Normal signing requires participation from the client side and Tatum’s MPC infrastructure. The complete blockchain private key does not need to exist during this flow.

Tatum cannot independently reconstruct a customer’s complete private key. It does not possess the client share and does not have direct access to the MPC share held in the secure enclave.

Key ejection is different from normal signing. It is an authorized, exceptional workflow that combines the required backup shares to reconstruct the wallet’s underlying blockchain private key. You can then move that key outside Tatum and manage it independently.

This gives organizations a defined migration and exit mechanism: Tatum Smart Wallet does not lock you into Tatum’s MPC infrastructure.

Why eject a wallet?

Organizations typically use key ejection when they need to change how they operate or custody existing wallets without abandoning the associated blockchain accounts and assets.

Migrate to another wallet or custody provider

Move an existing wallet to another wallet, custody, or signing provider while retaining the underlying blockchain key. This can avoid creating new blockchain addresses and transferring assets solely because you change infrastructure.

Terminate a Tatum account or commercial relationship

Plan key ejection as part of your offboarding procedure when you intend to stop using Tatum services and still require independent control of existing wallets.

For custodial deployments, your organization operates the Tatum integration on behalf of users. If that integration and the required Tatum service are no longer available, normal MPC wallet access and signing cannot continue.

For self-custody deployments, users who control the required client and recovery material can use the supported ejection process to obtain their private key and migrate independently, subject to the configured ejection flow. Terminating an account does not automatically eject, delete, or transfer private keys.

Meet business-continuity and vendor-exit requirements

Regulated institutions may need a documented provider-exit mechanism for vendor-risk management, operational resilience, or internal compliance. Key ejection lets you plan a transition away from Tatum’s MPC infrastructure without requiring entirely new wallets solely because your provider changes.

Move to internally managed custody

Transition from Tatum Smart Wallet to your own custody or key-management infrastructure. For example, you may decide to use an internal signing environment, an HSM (hardware security module), another MPC provider, or direct private-key custody.

Prepare for infrastructure or service availability changes

If you plan to stop relying on Tatum’s MPC service, eject keys before that change so future signing can occur independently. This is proactive continuity planning, not a guarantee that you can start ejection after Tatum infrastructure has already become permanently unavailable.

Satisfy regulatory or compliance requirements

Demonstrate that you have a custody-portability or direct-key-control option as part of your governance, audit, or compliance program.

What happens during key ejection?

During normal operation, MPC signs transactions without reconstructing the complete private key:

Client share + Tatum MPC participation
                ↓
           MPC signing
                ↓
Transaction signed without reconstructing the complete private key

During ejection, authorized backup material reconstructs the underlying key:

Client backup share + Tatum custodian backup share
                         ↓
             Authorized key-ejection process
                         ↓
      Complete blockchain private key reconstructed locally
                         ↓
          Key can be managed outside Tatum

A custodian enables ejection through enableEject() and defines an ejectableUntil time window. Tatum’s custodian backup share is available for ejection only during that configured window. The client backup share and Tatum custodian backup share are then used to reconstruct the private key locally.

For authorization requirements, backup retrieval, local reconstruction, and finalization, follow the canonical Eject keys implementation guide.

What you can do with the ejected private key

A successful ejection produces the wallet’s underlying blockchain private key, not another Tatum-specific wallet credential or MPC share. You can import or store it in compatible external systems, including:

• Wallet software
• Custody platforms
• Signing infrastructure
• HSM or key-management systems
• Another wallet provider
• Internally operated custody infrastructure

Compatibility depends on the destination supporting the relevant blockchain, cryptographic curve and key type, and expected private-key encoding or import format. Verify those requirements with the destination system before you begin a production migration.

Once you control the ejected key, you can sign blockchain transactions without Tatum’s MPC signing infrastructure. Treat the key as highly sensitive material: import or store it immediately using an appropriate secure custody mechanism, and do not log or transmit the private key or plaintext backup shares.

Important: plan your exit before you need it

Normal MPC signing depends on participation from Tatum’s infrastructure. The Tatum-side backup share is also available only during the custodian-configured ejectableUntil window. Do not assume you can contact Tatum or call an API to begin ejection after Tatum’s infrastructure has become permanently inaccessible.

Review the Eject keys guide with your security, custody, and continuity teams before defining your production exit procedure.

FAQ

If Tatum becomes unavailable, can we still recover or use the wallet without Tatum’s infrastructure?

For normal MPC signing, no. Normal signing requires participation from both the client side and Tatum’s MPC infrastructure.

Key ejection removes that dependency by reconstructing the complete private key. After successful ejection, you can manage and use the private key independently of Tatum. Plan and perform ejection as part of a proactive exit strategy; the documentation does not establish that ejection can be initiated after Tatum’s infrastructure has already become permanently unavailable.

Can Tatum reconstruct the complete private key on its own?

No. Tatum does not possess the client share and does not have direct access to the MPC share held within the secure enclave. Tatum provides the service and infrastructure that facilitates the MPC process, but it cannot independently combine the required key material to reconstruct a customer’s complete private key.

How does key ejection/export work?

A custodian authorizes ejection for a limited window, and the required backup shares are retrieved and combined locally to reconstruct the underlying blockchain private key. The client then completes the irreversible ejection process.

For the exact SDK workflow, see Eject keys.

During key ejection, which shares are required and who can trigger it?

The custodian enables ejection through enableEject(). Reconstruction requires the client backup share and Tatum’s custodian backup share, and access to the Tatum-side share is restricted to the configured ejectableUntil window.

See Eject keys for the exact authorization and retrieval workflow.

Does key ejection produce a standard blockchain private key that can be imported into another wallet?

Yes. Ejection reconstructs the wallet’s blockchain private key, rather than producing another Tatum-specific MPC share. You can use it with external wallet, custody, or signing software that supports the corresponding blockchain, cryptographic key type, and key encoding.

Do not assume every wallet application supports every key format or blockchain. Confirm the destination’s import requirements before migration.

What happens to existing wallets if we terminate our Tatum account?

If you operate custodial wallets whose signing depends on your Tatum Smart Wallet integration, normal MPC signing cannot continue when the required integration or Tatum service is no longer available. Include wallet migration and key ejection in your offboarding procedure whenever independent control of those wallets is required.

For self-custody deployments, users who control the required client and recovery material can use the supported ejection mechanism to take control of the underlying private key, subject to the configured ejection process. Account termination does not automatically export, delete, or transfer private keys.

Does ejecting a key change the blockchain address?

No. Reconstructing and exporting the existing wallet’s private key does not inherently create a new wallet. The key corresponds to the existing blockchain account or address, allowing you to migrate the existing wallet instead of moving assets to a newly generated address, where applicable to the relevant blockchain and key model.

Is key ejection the same as wallet recovery?

No. Recovery restores your ability to participate in the existing MPC signing model after you lose client signing material. Key ejection reconstructs the complete underlying private key so the wallet can leave the MPC system and operate independently.

For recovery planning and backup handling, see Wallet Backup & Recovery.

Next steps

• Follow Eject keys for the production implementation and security workflow.
• Review Wallet Backup & Recovery to plan and protect the backup material required for recovery and ejection.
• Review Smart Wallets for Banks for custodial operating-model and security responsibilities.
• For enterprise migrations involving large numbers of production wallets, coordinate the migration plan with your Tatum support or account team.