Summary
This proposal seeks whitelist approval for Lido validators to integrate the proposer MEV-Protect feature from bloXroute and Ultrasound relays:
Proposer MEV-Protect: A relay-side mechanism that ensures validators receive a fair share of block value. It enforces a minimum return of 90% of the block value to the proposer. If a block pays less, it must include an additional fee to be accepted. This model rejects underpaying blocks and introduces a fair revenue-sharing structure for blocks that fall below the threshold. The system encourages builder-proposer alignment, improves fairness in MEV distribution, and is projected to increase Execution Layer rewards by 10%.
Technical Specification
Proposer MEV-Protect
Proposer MEV-Protect is a relay-level safeguard that enforces a minimum value return of 90% from builders to proposers, or requires the inclusion of an additional fee.
Activation – Validators must connect only to relays that support the Proposer MEV Protect feature (currently limited to bloXroute and Ultrasound relays, with others expected to follow). This is enabled by appending ?proposer_mev_protect=true to the relay URL.
Policy –
- Blocks paying ≥ 90% of value are accepted with no fee.
- Blocks returning < 90% are automatically rejected unless an additional fee is included.
- When accepted, the additional fee is distributed as follows:
- â…“ of the builder profit goes to the validator
- â…“ goes to the relay
- â…“ remains with the builder
Operational Transparency & Incident Handling
bloXroute maintains a transparent policy around incident handling. In the event of a missed proposal caused by its infrastructure, bloXroute:
- Proactively investigates the root cause.
- If found to be at fault, deploys a fix and issues a refund of up to 10 ETH and.
- Publishes a post-mortem summary for any confirmed incidents.
- If the cause is shared with a third party (e.g., a builder), bloXroute coordinates directly to resolve the issue and ensure fair compensation.
Testing and Reliability
bloXroute’s relay has been thoroughly tested in both testnet and mainnet environments.
Testnet Availability:
Proposer MEV-Protect Pilot
We request that Lido allocate a subset of validator keys to participate in a pilot program evaluating the impact of Proposer MEV-Protect. Most large Lido node operators intend to participate in the pilot using their own non-Lido public keys. It is expected to be straightforward for them to additionally assign a portion of their Lido-operated keys to the trial. This will enable a representative evaluation of performance and value outcomes within Lido’s validator set.
Revenue and Governance Model
There is no additional cost to use the Proposer MEV-Protect feature. The system enforces fee-sharing for blocks below the 90% threshold (for the pilot, we will support a list of whitelisted builders). In those cases:
- 33% of retained builder value is sent to the validator
- 33% is sent to the relay
- 33% remains with the builder
Impact Analysis: Lido Validator Rewards
Date Range Analyzed: April 16, 2025 – May 29, 2025
Total Blocks Analyzed: 279,000
Lido-Specific Metrics:
- Total Lido Blocks: 71,742
- Original Rewards: 3,577 ETH
- Protected Rewards: 3,939 ETH
- Projected Increase: +10% in proposer payments
This suggests Lido would have received an additional 10% in ETH rewards with MEV-Protect enforcement during the observed period.
The graph below illustrates the additional rewards Lido could have earned across the top blocks in the specified time range:
Proposed Integration & Implementation
​To enable Proposer MEV-Protect, Lido node operators must connect only to relays that support the feature and add the query parameter ?proposer_mev_protect=true. For example, to enable it on the bloXroute relay:
-relays \
http://0x8b5d2e73e2a3a55c6c87b8b6eb92e0149a125c852751db1422fa951e42a09b82c142c3ea98d0d9930b056a3bc9896b8f@bloxroute.max-profit.blxrbdn.com?proposer_mev_protect=true&id=validator-name,\
http://0x8b5d2e73e2a3a55c6c87b8b6eb92e0149a125c852751db1422fa951e42a09b82c142c3ea98d0d9930b056a3bc9896b8f@bloxroute.regulated.blxrbdn.com?proposer_mev_protect=true&id=validator-name \
- No hardware upgrades or local software changes are required.
- Integration takes effect immediately, with performance benefits visible shortly after activation.
Ethics and Values
bloXroute’s infrastructure is built to support validators of all sizes—ranging from individual operators to institutional node runners. Proposer MEV-Protect is designed to enhance performance, transparency, and ecosystem alignment without adding operational burden.
bloXroute’s relays are publicly accessible, open to third-party builders, and maintained with a strong commitment to transparency. The codebase is open-source and integrates seamlessly into standard validator workflows, promoting decentralization and builder diversity.
Proposer MEV-Protect was developed to foster alignment between builders and validators—not to penalize. By introducing transparent thresholds and value-sharing expectations, it encourages collaborative participation in the Ethereum MEV ecosystem.
Call to Action
We invite the Lido DAO to approve and enable participation in Proposer MEV-Protect. This feature strengthens validator infrastructure and establishes clear standards for value distribution—without introducing operational complexity.
The feature is non-invasive and requires only a configuration update to the MEV-Boost sidecar (e.g., MEV-Boost, Vouch, or Commit-Boost). Validators simply append bloXroute’s relay URL—along with a query parameter to enable MEV-Protect—to the relay arguments. It is designed to work seamlessly with Lido’s validator set across all clients and geographies.
bloXroute is committed to supporting Lido’s mission of secure, decentralized, and high-performing Ethereum staking. We welcome the opportunity to collaborate further, share trial metrics, and tailor the rollout to Lido’s validator footprint and governance processes.
Additional Resources
- Documentation: Proposer MEV Protect
- GitHub: bloXroute-Labs/mev-relay
- Email: [email protected]
