Withdraw Overview

1. Initiate - BitGo uses the data you pass in this call to build an unsigned transaction.
2. Approve (Optional) - You can configure a wallet policy to require admin approval for all outgoing transactions, providing an extra layer of security. Transactions remain in a pending-approval status until final approval. Approving a transaction doesn't apply a signature.
3. Sign - Conduct video verification with a BitGo operator. Once verified, BitGo does the following:
   1. Uploads the unsigned transaction to the BitGo Offline Vault Console (OVC).
   2. Uses the user key to sign the unsigned transaction in the OVC, becoming a half-signed transaction.
   3. Uses the BitGo key to sign the half-signed transaction in a hardware security module (HSM), creating a fully-signed transaction.
4. Broadcast - Using a BitGo node, BitGo broadcasts the transaction to the network for confirmation.

1. Request - BitGo uses the data you pass in this call to build an unsigned transaction.
2. Approve - Admins must approve all outgoing transactions, providing an extra layer of security. Transactions remain in a pending-approval status until final approval. Approving a transaction doesn't apply a signature.
3. Sign - Conduct video verification with a BitGo operator. Once verified, BitGo does the following:
   1. Uploads the unsigned transaction to the BitGo Offline Vault Console (OVC).
   2. Uses the user key to sign the unsigned transaction in the OVC, becoming a half-signed transaction.
   3. Uses the BitGo key to sign the half-signed transaction in a hardware security module (HSM), creating a fully-signed transaction.
4. Broadcast - Using a BitGo node, BitGo broadcasts the transaction to the network for confirmation.

Go Accounts are a type of custody multisignature wallet, but they follow a unique transaction flow. To set up trading for your Go Account, see Trading Overview. The following is the manual transaction flow for withdrawing assets from your Go Account:

1. Build - BitGo uses the information you pass in this call to build an unsigned transaction.
2. Send - You send the unsigned transaction to BitGo to receive signing.
3. Approve (Optional) - You can configure a wallet policy to require admin approval for all outgoing transactions, providing an extra layer of security. Transactions remain in a pending-approval status until final approval. Approving a transaction doesn't apply a signature.
4. Authorize - Depending on your Go Account policies, you may need to conduct video verification with a BitGo operator. Once verified, or if verification isn't required, BitGo does the following:
   1. Uploads the unsigned transaction to the BitGo Offline Vault Console (OVC).
   2. Uses the user key to sign the unsigned transaction in the OVC, becoming a half-signed transaction.
   3. Uses the BitGo key to sign the half-signed transaction in a hardware security module (HSM), creating a fully-signed transaction.
5. Broadcast - Using the BitGo key for the wallet, BitGo signs the half-signed transaction in a hardware security module (HSM), creating a fully-signed transaction. Using a BitGo node, BitGo broadcasts the transaction to the network for confirmation.

Go Accounts are a type of custody multisignature wallet, but they follow a unique transaction flow. To set up trading for your Go Account, see Trading Overview. The following is the Express flow for withdrawing assets from your Go Account:

1. Send - You build and send an unsigned transaction to BitGo to receive signing. The SDK invokes the same endpoint as it does for a manual send transaction. However, Express integrations call a different endpoint.
   • Send Transaction - Express
   • Send Half-Signed Transaction - SDK
2. Approve (Optional) - You can configure a wallet policy to require admin approval for all outgoing transactions, providing an extra layer of security. Transactions remain in a pending-approval status until final approval. Approving a transaction doesn't apply a signature. Once approved, you rebuild the transaction, getting the most current on-chain data, such as nonce and fees.
3. Authorize - Depending on your Go Account policies, you may need to conduct video verification with a BitGo operator. Once verified, or if verification isn't required, BitGo does the following:
   1. Uploads the unsigned transaction to the BitGo Offline Vault Console (OVC).
   2. Uses the user key to sign the unsigned transaction in the OVC, becoming a half-signed transaction.
   3. Uses the BitGo key to sign the half-signed transaction in a hardware security module (HSM), creating a fully-signed transaction.
4. Broadcast - Using the BitGo key for the wallet, BitGo signs the half-signed transaction in a hardware security module (HSM), creating a fully-signed transaction. Using a BitGo node, BitGo broadcasts the transaction to the network for confirmation.

1. Build - BitGo uses the data you pass in this call to build an unsigned transaction.
2. Sign Offline - Upload the unsigned transaction to the BitGo Offline Vault Console (OVC). Wallet co-signers login to the OVC and sign the transaction, resulting in a partially-signed transaction. Once all required wallet co-signers sign the transaction, it becomes a half-signed transaction.
3. Send - You send the half-signed transaction to BitGo to receive the final signature.
4. Approve (Optional) - You can configure a wallet policy to require admin approval for all outgoing transactions, providing an extra layer of security. Transactions remain in a pending-approval status until final approval. Approving a transaction doesn't apply a signature. Once approved, you rebuild and re-sign the transaction, getting the most current on-chain data, such as nonce and fees.
5. Broadcast - Using the BitGo key for the wallet, BitGo signs the half-signed transaction in a hardware security module (HSM), creating a fully-signed transaction. Using a BitGo node, BitGo broadcasts the transaction to the network for confirmation.

1. Build - BitGo uses the data you pass in this call to build an unsigned transaction.
2. Sign - Wallet co-signers sign the transaction using their wallet passwords, resulting in a partially-signed transaction. Once all required wallet co-signers sign the transaction, it becomes a half-signed transaction. You can use either of the following two options for signing:
   • Sign - Decrypt your private key and sign transactions using REST protocol in a network-connected environment.
   • Sign Wallet Transaction - Decrypt your private key and sign transactions using external-signer mode in an air-gapped environment.
3. Send - You send the half-signed transaction to BitGo to receive the final signature.
4. Approve (Optional) - You can configure a wallet policy to require admin approval for all outgoing transactions, providing an extra layer of security. Transactions remain in a pending-approval status until final approval. Approving a transaction doesn't apply a signature. Once approved, you rebuild and re-sign the transaction, getting the most current on-chain data, such as nonce and fees.
5. Broadcast - Using the BitGo key for the wallet, BitGo signs the half-signed transaction in a hardware security module (HSM), creating a fully-signed transaction. Using a BitGo node, BitGo broadcasts the transaction to the network for confirmation.

1. Send - You build, sign, and send a half-signed transaction to BitGo to receive the final signature.
2. Approve (Optional) - You can configure a wallet policy to require admin approval for all outgoing transactions, providing an extra layer of security. Transactions remain in a pending-approval status until final approval. Approving a transaction doesn't apply a signature. Once approved, you rebuild and re-sign the transaction, getting the most current on-chain data, such as nonce and fees.
3. Broadcast - Using the BitGo key for the wallet, BitGo signs the half-signed transaction in a hardware security module (HSM), creating a fully-signed transaction. Using a BitGo node, BitGo broadcasts the transaction to the network for confirmation.

1. Request - BitGo uses the data you pass in this call to build an unsigned transaction.
2. Approve (Optional) - You can configure a wallet policy to require admin approval for all outgoing transactions, providing an extra layer of security. Transactions remain in a pending-approval status until final approval. Approving a transaction doesn't apply a signature. Once approved, you rebuild and re-sign the transaction, getting the most current on-chain data, such as nonce and fees.
3. Sign - Wallet co-signers and BitGo sign the transaction using signature shares - a collection of key shares made up of public shares and encrypted private shares that when combined, create a full signature. Once all required wallet co-signers sign the transaction, it becomes a half-signed transaction and is automatically sent to BitGo. You can use either of the following two options for signing:
   • Sign MPC Transaction - Use Express to decrypt your private key shares and sign transactions. This route supports both REST protocol in a network-connected environment or external-signer mode in an air-gapped environment.
   • Use the SDK to decrypt your private shares through signature sharing, an orchestrated process that involves the following 3 consecutive API calls:
     1. Create a Signature Share - You send the 1st key share to BitGo. This enables BitGo to make the 2nd key share and returns the transaction request ID that you use for the rest of the transaction process.
     2. Get Transaction Requests - You get the 2nd key share from BitGo. This enables you to make the 3rd key share.
     3. Create a Signature Share - You send the 3rd key share to BitGo. This enables BitGo to create the 4th, and final, key share, completing the signature share and becoming a half-signed transaction request.
4. Broadcast - Using the BitGo key for the wallet, BitGo signs the half-signed transaction in a hardware security module (HSM), creating a fully-signed transaction. Using a BitGo node, BitGo broadcasts the transaction to the network for confirmation.

1. Send - You build, sign, and send a half-signed transaction to BitGo to receive the final signature. Simple MPC transactions are possible only with the SDK, which invokes the following endpoints:
   1. Create a Signature Share - You send the 1st key share to BitGo. This enables BitGo to make the 2nd key share and returns the transaction request ID that you use for the rest of the transaction process.
   2. Get Transaction Requests - You get the 2nd key share from BitGo. This enables you to make the 3rd key share.
   3. Create a Signature Share - You send the 3rd key share to BitGo. This enables BitGo to create the 4th, and final, key share, completing the signature share and becoming a half-signed transaction request.
2. Approve (Optional) - You can configure a wallet policy to require admin approval for all outgoing transactions, providing an extra layer of security. Transactions remain in a pending-approval status until final approval. Approving a transaction doesn't apply a signature. Once approved, you rebuild and re-sign the transaction, getting the most current on-chain data, such as nonce and fees.
3. Broadcast - Using the BitGo key for the wallet, BitGo signs the half-signed transaction in a hardware security module (HSM), creating a fully-signed transaction. Using a BitGo node, BitGo broadcasts the transaction to the network for confirmation.