Programmable privacy

Merkle gives users advanced privacy control over their transactions in the private pool.

Profiles

Four privacy profiles are available when sending a transaction:

• Public (public): all parts of the transaction are leaked to searchers.

• Private (private): no parts of the transaction except logs are leaked to searchers (transaction is only revealed when mined on-chain).

• Semi-private (default): The to, from, value, nonce, gas limit, logs and data fields of the transaction are leaked to searchers. This is the default.

• Custom (custom): Provide a custom list of hints (see below).

Advanced privacy

In addition to the privacy profiles, Merkle offers advanced custom privacy settings via hints. When sending a transaction, a user can include a list of hints to leak to searchers. The list of hints is as follow:

• to: leaks the to field of the transaction.

• from: leaks the from field of the transaction.

• function_selector: leaks the first 4 bytes of the data field.

• swap_logs: only leaks swap-related logs (uniswap, balancer and curve swaps).

• value: leaks the value field of the transaction.

• nonce: leaks the nonce field of the transaction.

• data: leaks the data field of the transaction.

• gas_limit: leaks the gas field of the transaction.

• gas_price: leaks the gas fee cap and priority fee to searchers.

• logs: leaks the list of logs generated by the transaction to searchers.

All MEV-Share privacy hints are valid and automatically translated to their correct equivalent in the merkle private mempool.

Bundle types

The Merkle private pool offers additional advanced settings for advanced users. The bundle type field tells Merkle what kind of bundle is allowed with the user's transaction. The possible types of bundles are:

• backrun: allow only bundles that backrun the transaction. Searchers will only be allowed to put a transaction after your transaction. This is the default.

• none: do not allow any bundles. Searchers are not allowed to bid on this transaction.