Swap security

Private RPC routing: which protections should you verify?

Compare private transaction services by chain support, information sharing, fallback and execution rules rather than the word private.

A private RPC routes submitted transactions through a restricted path instead of ordinary public propagation. Its protections depend on the service’s actual configuration and participating infrastructure.

Verify four properties

PropertyQuestion to answer
Chain supportDoes this endpoint handle the chain you are using?
Data sharingWhich builders or other participants receive transaction information?
FallbackCan the transaction later be sent to the public mempool?
Failure handlingAre reverting transactions filtered, and under which settings?

Flashbots’ settings guide illustrates that sharing and revert behavior can be configured. Its quick start explicitly identifies trust in builders and supported network information.

Do not equate restricted propagation with secrecy forever

After inclusion, ordinary public-chain execution remains visible. The service may also receive information before inclusion. Read its current policy rather than assuming no intermediary can observe the transaction.

A private route does not validate a malicious token approval or make a wrong recipient correct. It addresses aspects of propagation and ordering, not every signing risk.

Check what your wallet actually uses

An aggregator or wallet may submit through its own infrastructure. Changing a general RPC setting does not prove every route follows that setting. Verify the integration’s documentation and transaction status path.

If a private transaction stalls, use the service’s documented recovery process. Blindly switching endpoints can change its exposure before you have resolved the old request.

Sources & verification (4)

Source-check date is recorded in the article details. URLs are provided for manual verification. Use Copy to keep this page open.

  1. Settings Guide | Flashbots Docs

    Configurable sharing, builder trust, revert protection and public routing settings.

    https://docs.flashbots.net/flashbots-protect/settings-guide
  2. Quick Start | Flashbots Docs

    Supported chain scope, builder trust and warning that RPC switching may rebroadcast pending private transactions.

    https://docs.flashbots.net/flashbots-protect/quick-start
  3. Fixing Stuck Transactions | Flashbots Docs

    Private transaction pending state and supported troubleshooting.

    https://docs.flashbots.net/flashbots-protect/stuck_transactions
  4. Why digital privacy matters | ethereum.org

    Public-chain visibility and privacy considerations.

    https://ethereum.org/privacy/

Continue reading

Can switching RPCs expose a previously private swap? How to reduce sandwich exposure when swapping