# Robinhood Chain

Markdown version of https://l2beat.com/layer2s/projects/robinhood

## Summary

**Warning:** Why is the project listed in others? There are less than 5 external actors that can submit challenges. Consequence: projects without a sufficiently decentralized set of challengers rely on few entities to safely update the state. A small set of challengers can collude with the proposer to finalize an invalid state, which can cause loss of funds. Learn more about the [recategorisation](https://medium.com/l2beat/framework-update-l2-projects-recategorisation-5d43b0d1fe50).

- Total Value Secured: $2.46 B (-3.92% compared to seven days ago; canonically bridged $655.29 M, natively minted $607.31 M, externally bridged $1.20 B; 48.7% with additional trust assumptions compared to the tokens involved and the Stage assigned to the project's canonical messaging bridge)
- TVS by asset: ETH & derivatives $649.88 M (26.3%), Stablecoins $1.19 B (48.6%), Other $457.25 M (18.5%), Public RWAs $158.64 M (6.43%)
- Past day UOPS: 79.25 (+21.7% compared to seven days ago)
- Gas token: ETH
- Type: Other
- Purposes: Universal, RWA
- Host chain: Ethereum
- Chain ID: 4663
- Last 24h cross-chain volume: $50.18 M
- Last 24h cross-chain transfers: 18.07 K
- Interop protocols used (last 24h volume): [LayerZero](https://l2beat.com/interop/protocols/layerzero) ($26.85 M), [Across](https://l2beat.com/interop/protocols/across) ($10.70 M), [Robinhood Chain Canonical](https://l2beat.com/interop/protocols/robinhood) ($4.58 M), and 7 more
- Tokens by volume (last 24h): [USDG](https://l2beat.com/interop/tokens/ibIzBF/usdg) ($26.67 M), [ETH](https://l2beat.com/interop/tokens/C0Hmkq/eth) ($12.40 M), [USDe](https://l2beat.com/interop/tokens/tmyD4t/usde) ($6.62 M), and 231 more

### Risks

- Sequencer failure: No mechanism (sentiment: bad)
- State validation: Fraud proofs (INT) (6d 8h challenge period + 2d execution delay; sentiment: bad)
- Data availability: Onchain (sentiment: good)
- Exit window: None (sentiment: bad)
- Proposer failure: Self propose (28d delay; sentiment: good)

### About

Robinhood Chain is an Arbitrum Orbit Layer 2 operated by Robinhood, focused on tokenized real-world assets (such as stocks and ETFs) and onchain financial services including 24/7 trading, lending, and borrowing.

Robinhood Chain is part of Robinhood's broader mission to democratize access to global financial markets and to empower users and developers with modern blockchain tools.

### Links

- Website: https://robinhood.com/chain/
- Bridge: https://portal.arbitrum.io/bridge?destinationChain=robinhood-chain&sourceChain=ethereum
- Docs: https://docs.robinhood.com/chain
- Explorer: https://robin.etherscan.io, https://robinhoodchain.blockscout.com
- Social: https://x.com/RobinhoodApp
- Contracts explorer (Disco): https://disco.l2beat.com/ui/p/robinhood

### Badges

- EVM: This project uses the Ethereum Virtual Machine to run its smart contracts and supports the Solidity programming language
- Ethereum with blobs: This project is posting its data to Ethereum as blobs
- Built on Arbitrum Orbit: The project is built on Arbitrum Orbit
- L3 Host Chain: This project serves as a host chain for L3s

## Value Secured

The interactive TVS charts are shown on [the HTML page](https://l2beat.com/layer2s/projects/robinhood#tvs).

Token by token: [TVS breakdown](https://l2beat.com/layer2s/projects/robinhood/tvs-breakdown).

- [TVS chart (JSON)](https://l2beat.com/api/scaling/tvs/robinhood)
- [TVS breakdown by token (JSON)](https://l2beat.com/api/scaling/tvs/robinhood/breakdown)

## Volume and flows

The interactive flows chart is shown on [the HTML page](https://l2beat.com/layer2s/projects/robinhood#interop-flows).

## Activity

The interactive activity chart is shown on [the HTML page](https://l2beat.com/layer2s/projects/robinhood#activity).

- [Activity chart (JSON)](https://l2beat.com/api/scaling/activity/robinhood)

## Onchain costs

The section shows the operating costs that L2s pay to Ethereum.

The interactive costs chart is shown on [the HTML page](https://l2beat.com/layer2s/projects/robinhood#onchain-costs).

### Tracked transactions

#### Batch submissions

- functionCall: 2026-04-30 16:51 UTC - now; currently used; address: [0xBd0D173EEb87D57A09521c24388a12789F33ba96](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96); selector: 0xe0bc9729; signature: `function addSequencerL2Batch(uint256 sequenceNumber,bytes calldata data,uint256 afterDelayedMessagesRead,address gasRefunder,uint256 prevMessageCount,uint256 newMessageCount)`
- functionCall: 2026-04-30 16:51 UTC - now; currently used; address: [0xBd0D173EEb87D57A09521c24388a12789F33ba96](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96); selector: 0x8f111f3c; signature: `function addSequencerL2BatchFromOrigin(uint256 sequenceNumber,bytes data,uint256 afterDelayedMessagesRead,address gasRefunder,uint256 prevMessageCount,uint256 newMessageCount)`
- functionCall: 2026-04-30 16:51 UTC - now; currently used; address: [0xBd0D173EEb87D57A09521c24388a12789F33ba96](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96); selector: 0x69cacded; signature: `function addSequencerL2BatchFromOriginDelayProof(uint256 sequenceNumber, bytes data, uint256 afterDelayedMessagesRead, address gasRefunder, uint256 prevMessageCount, uint256 newMessageCount, tuple(bytes32 beforeDelayedAcc, tuple(uint8 kind, address sender, uint64 blockNumber, uint64 timestamp, uint256 inboxSeqNum, uint256 baseFeeL1, bytes32 messageDataHash) delayedMessage) delayProof)`
- functionCall: 2026-04-30 16:51 UTC - now; currently used; address: [0xBd0D173EEb87D57A09521c24388a12789F33ba96](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96); selector: 0x3e5aa082; signature: `function addSequencerL2BatchFromBlobs(uint256 sequenceNumber,uint256 afterDelayedMessagesRead,address gasRefunder,uint256 prevMessageCount,uint256 newMessageCount)`
- functionCall: 2026-04-30 16:51 UTC - now; currently used; address: [0xBd0D173EEb87D57A09521c24388a12789F33ba96](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96); selector: 0x917cf8ac; signature: `function addSequencerL2BatchFromBlobsDelayProof(uint256 sequenceNumber, uint256 afterDelayedMessagesRead, address gasRefunder, uint256 prevMessageCount, uint256 newMessageCount, tuple(bytes32 beforeDelayedAcc, tuple(uint8 kind, address sender, uint64 blockNumber, uint64 timestamp, uint256 inboxSeqNum, uint256 baseFeeL1, bytes32 messageDataHash) delayedMessage) delayProof)`

#### State updates

- functionCall: 2026-04-30 16:51 UTC - now; currently used; address: [0xf0ce991ea4A0d2400A4AB49b20ae333f6Dce3DE9](https://etherscan.io/address/0xf0ce991ea4A0d2400A4AB49b20ae333f6Dce3DE9); selector: 0xa04cee60; signature: `function updateSendRoot(bytes32 root, bytes32 l2BlockHash) external`

## Data posted

This section shows how much data the project publishes to Ethereum over time. It leaves out data posted to other data-availability (DA) layers. The project currently posts data to [Ethereum](https://l2beat.com/projects/ethereum).

The interactive data posted chart is shown on [the HTML page](https://l2beat.com/layer2s/projects/robinhood#data-posted).

### Tracked transactions

#### Blob submissions

- DA layer Ethereum: from block 24994238 to now; currently used; inbox: [0xBd0D173EEb87D57A09521c24388a12789F33ba96](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96); sequencers: [0xDaa526086787d9DEbE1D7F3FFdb1fE50cf8687F4](https://etherscan.io/address/0xDaa526086787d9DEbE1D7F3FFdb1fE50cf8687F4)

## Liveness

This section shows how "live" the project's operators are by displaying how frequently they submit transactions of the selected type. It also highlights anomalies - significant deviations from their typical schedule.

No ongoing anomalies detected.

The interactive liveness chart is shown on [the HTML page](https://l2beat.com/layer2s/projects/robinhood#liveness).

### Tracked transactions

#### Batch submissions

- functionCall: 2026-04-30 16:51 UTC - now; currently used; address: [0xBd0D173EEb87D57A09521c24388a12789F33ba96](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96); selector: 0xe0bc9729; signature: `function addSequencerL2Batch(uint256 sequenceNumber,bytes calldata data,uint256 afterDelayedMessagesRead,address gasRefunder,uint256 prevMessageCount,uint256 newMessageCount)`
- functionCall: 2026-04-30 16:51 UTC - now; currently used; address: [0xBd0D173EEb87D57A09521c24388a12789F33ba96](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96); selector: 0x8f111f3c; signature: `function addSequencerL2BatchFromOrigin(uint256 sequenceNumber,bytes data,uint256 afterDelayedMessagesRead,address gasRefunder,uint256 prevMessageCount,uint256 newMessageCount)`
- functionCall: 2026-04-30 16:51 UTC - now; currently used; address: [0xBd0D173EEb87D57A09521c24388a12789F33ba96](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96); selector: 0x69cacded; signature: `function addSequencerL2BatchFromOriginDelayProof(uint256 sequenceNumber, bytes data, uint256 afterDelayedMessagesRead, address gasRefunder, uint256 prevMessageCount, uint256 newMessageCount, tuple(bytes32 beforeDelayedAcc, tuple(uint8 kind, address sender, uint64 blockNumber, uint64 timestamp, uint256 inboxSeqNum, uint256 baseFeeL1, bytes32 messageDataHash) delayedMessage) delayProof)`
- functionCall: 2026-04-30 16:51 UTC - now; currently used; address: [0xBd0D173EEb87D57A09521c24388a12789F33ba96](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96); selector: 0x3e5aa082; signature: `function addSequencerL2BatchFromBlobs(uint256 sequenceNumber,uint256 afterDelayedMessagesRead,address gasRefunder,uint256 prevMessageCount,uint256 newMessageCount)`
- functionCall: 2026-04-30 16:51 UTC - now; currently used; address: [0xBd0D173EEb87D57A09521c24388a12789F33ba96](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96); selector: 0x917cf8ac; signature: `function addSequencerL2BatchFromBlobsDelayProof(uint256 sequenceNumber, uint256 afterDelayedMessagesRead, address gasRefunder, uint256 prevMessageCount, uint256 newMessageCount, tuple(bytes32 beforeDelayedAcc, tuple(uint8 kind, address sender, uint64 blockNumber, uint64 timestamp, uint256 inboxSeqNum, uint256 baseFeeL1, bytes32 messageDataHash) delayedMessage) delayProof)`

#### State updates

- functionCall: 2026-04-30 16:51 UTC - now; currently used; address: [0xf0ce991ea4A0d2400A4AB49b20ae333f6Dce3DE9](https://etherscan.io/address/0xf0ce991ea4A0d2400A4AB49b20ae333f6Dce3DE9); selector: 0xa04cee60; signature: `function updateSendRoot(bytes32 root, bytes32 l2BlockHash) external`

## Milestones & Incidents

- 2026-07-01: [Mainnet launch](https://robinhood.com/chain/). Robinhood Chain opens to the public, removing the transaction-access whitelist.
- 2026-02-10: [Public testnet launch](https://robinhood.com/us/en/newsroom/robinhood-chain-launches-public-testnet/). Robinhood Chain opens its public testnet.

## Risk summary

**Warning:** Fraud proof system is fully deployed but is not yet permissionless as it requires Validators to be whitelisted.

### Funds can be stolen if

1. a contract receives a malicious code upgrade. There is no delay on code upgrades (CRITICAL),
2. no whitelisted challenger disputes an invalid state root before the challenge window expires (CRITICAL),
3. an attacker successfully performs a resource exhaustion attack.

### Users can be censored if

4. the operator registers their transaction hash in the ArbFilteredTransactionsManager precompile, causing the state transition function to fail it even when it is force-included via the L1 delayed inbox.

### MEV can be extracted if

5. the operator exploits their centralized position and frontruns user transactions.

## Risk analysis

**Warning:** Fraud proof system is fully deployed but is not yet permissionless as it requires Validators to be whitelisted.

### Sequencer failure

No mechanism (sentiment: bad)

There is no guaranteed mechanism to have transactions included if the sequencer is down or censoring. Although users can enqueue messages in the L1 delayed inbox and call forceInclusion on the SequencerInbox, the chain runs ArbOS 61 transaction filtering: an authorized filterer can register any transaction hash in the ArbFilteredTransactionsManager precompile (0x00…0074), after which the state transition function forcibly fails that transaction, including force-included ones, without delay.

### State validation

Fraud proofs (INT) (6d 8h challenge period + 2d execution delay; sentiment: bad)

Fraud proofs only allow 2 WHITELISTED actors watching the chain to prove that the state is incorrect. Interactive proofs (INT) require multiple transactions over time to resolve. The challenge protocol can be subject to delay attacks. There is a 6d 8h challenge period.

### Data availability

Onchain (sentiment: good)

All of the data needed for proof construction is published on Ethereum L1.

### Exit window

None (sentiment: bad)

There is no window for users to exit in case of an unwanted upgrade since contracts are instantly upgradable.

### Proposer failure

Self propose (28d delay; sentiment: good)

Anyone can become a Proposer after 28d of inactivity from the currently whitelisted Proposers.

## Stage

Robinhood Chain is not even a Stage 0 project.

**Warning:** The requirement for available node software is under review

### Stage 0

1 issue needs fixing.

- Met: A complete and functional proof system is deployed.
- Met: The project calls itself a rollup.
- Met: State roots are posted to Ethereum L1.
- Met: Inputs for the state transition function are posted to Ethereum L1.
- Under review: A source-available node exists that can recreate the state from Ethereum L1 data. Please note that the L2BEAT team has not verified the validity of the node source code.
- Issue: Fraud proof submission is not sufficiently decentralized.

### Stage 1

3 issues need fixing.

**Principle**

- Issue: Compromising ≥75% of the Security Council should be the only way (other than bugs) for a rollup to indefinitely block an L2→L1 message (e.g. a withdrawal) or push an invalid L2→L1 message (e.g. an invalid withdrawal) with a <7d exit window.

**Guidelines**

- Met: Users are able to exit without the help of the permissioned operators.
- Met: The sources of all programs used are public and program hashes can be independently regenerated.
- Issue: Upgrades executed by actors with more centralized control than a Security Council provide less than 7d for users to exit if the permissioned operator is down or censoring.
- Issue: The Security Council is not properly set up.

### Stage 2

3 issues need fixing.

- Issue: Fraud proof submission is open only to whitelisted actors.
- Issue: Upgrades unrelated to onchain provable bugs provide less than 30d to exit.
- Issue: The Security Council's actions are not confined to onchain provable bugs.

[Learn more about Stages](https://l2beat.com/stages).

Please keep in mind that these stages do not reflect project security, this is an opinionated assessment of project maturity based on subjective criteria, created with a goal of incentivizing projects to push toward better decentralization. Each team may have taken different paths to achieve this goal.

## Data availability

### All data required for proofs is published on chain

All the data that is used to construct the system state is published on chain in the form of cheap blobs or calldata. This ensures that it will be available for enough time.

**References**

- [Sequencing followed by deterministic execution - Arbitrum documentation](https://developer.offchainlabs.com/inside-arbitrum-nitro/#sequencing-followed-by-deterministic-execution)
- [SequencerInbox.sol - source code, addSequencerL2BatchFromOrigin function](https://etherscan.io/address/0xb015D78fb9B890e96FD3E23819b2C8D9fffA3cC5#code)

Learn more about the DA layer here: [Ethereum](https://l2beat.com/projects/ethereum)

## State validation

![A diagram of the state validation](https://l2beat.com/static/images/state-validation/bold.bb41beaf.png)

Updates to the system state can be proposed and challenged by a set of whitelisted validators. If a state root passes the challenge period, it is optimistically considered correct and made actionable for withdrawals.

### State root proposals

Validators propose state roots as children of a previous state root. A state root can have multiple conflicting children. State roots are referred to as "assertions" within the contracts. Each chain of assertions only requires one stake, and validators staked on assertions with a child are considered inactive and can either move their stake to a new node or withdraw it. The function used to propose a new assertion is the `stakeOnNewAssertion` function. The stake is currently set to 1.0 ETH, and it can be slashed if the proposal is proven incorrect via a fraud proof. The protocol allows such funds to be trustlessly pooled together if necessary. New nodes cannot be created faster than the minimum assertion period, currently set to 15m. An assertion without "rivals" can be confirmed after the challenge period has passed, currently set to 6d 8h. If a rival is present, then it is checked that the assertion is the winner in the challenge protocol.

**Risks**

- Funds can be stolen if no whitelisted challenger disputes an invalid state root before the challenge window expires (CRITICAL).

**References**

- [BoLD paper](https://arxiv.org/pdf/2404.10491)

### Challenges

A challenge can be started between two siblings, i.e. two different state roots that share the same parent, by calling the `createLayerZeroEdge` function in the `ChallengeManager` contract. Edges represent assertions, or bisected assertions, within the challenge protocol. Challenges are played via a bisection game, where asserters and challengers play together to find the first instruction of disagreement. Such instruction is then executed onchain in the WASM OneStepProver contract to determine the winner. An edge can only be bisected when rivaled. The bisection process requires no new stake as their validity is checked against a parent "history root" that contains all intermediate states. An edge can also be confirmed if itself or its descendants spend enough time being unrivaled. Such time is set to 6d 8h. If both actors play as slow as possible, the maximum time to confirm an edge is double such value, i.e. 12d 17h. Due to the complexities of maintaining the history root, the challenge protocol is divided into 3 levels, where the lowest level represents assertions over blocks, the highest level represents assertions over single WASM instructions, and intermediate levels represent assertions over chunks of WASM instructions. When moving between levels, a new stake is required. Level 0 (block level) requires a stake of 0.0 ETH, level 1 requires a stake of 0.000000000000000001 ETH, level 2 requires a stake of 0.000000000000000001 ETH. The ratio between such stakes can be exploited to perform resource exhaustion attacks.

**Risks**

- Funds can be stolen if an attacker successfully performs a resource exhaustion attack.

**References**

- [Fraud Proof Wars: Arbitrum BoLD](https://medium.com/l2beat/fraud-proof-wars-b0cb4d0f452a)

### Program Hashes

#### ArbOS wasmModuleRoot v61

A commitment to the exact WASM binary version used for Orbit stack optimistic dispute games.

- Hash: `0xc10cd7ec6acaf1c441a3f6bd0900ad20f15855ba775a96f1939118cbc629dc97`
- Repository: https://github.com/OffchainLabs/nitro/tree/consensus-v61/arbos
- Verification: successful
- Used in: [Arbitrum One](https://l2beat.com/layer2s/projects/arbitrum), [Robinhood Chain](https://l2beat.com/layer2s/projects/robinhood), [Arbitrum Nova](https://l2beat.com/layer2s/projects/nova)

##### Verification steps

Even though the program is compiled in docker for reproducibility reasons, it gives the correct results only on linux OS. Steps below were done on Ubuntu 22.04 OS. The steps below consume ~95 GiB disk space.

1. Install docker [https://docs.docker.com/get-started/get-docker/](https://docs.docker.com/get-started/get-docker/).
2. Checkout the correct branch in [nitro](https://github.com/OffchainLabs/nitro) repo: `git checkout consensus-v61` . Commit hash should be `dfab1dea5c8d2c5089eb26d22ad6239bb78cfa5d`.
3. Update git submodules `git submodule update --init --recursive --force`.
4. Fix a dependency on a private repo in `Dockerfile`: replace line `RUN --mount=type=secret,id=gh_token,required=false ./download-machine.sh consensus-v60-rc.3 0xeadc910d36a0eab43a3dd7acb1a3513885e333785689c7cf750b9949c5bb7227 OffchainLabs/nitro-private` with `RUN ./download-machine.sh consensus-v60-rc.5 0x7a9e6a77354888257a9989ce0b6bb39df5fedf222d453932933fdf7a489cbb57`.
4. Generate wasm module root in docker: `docker buildx build --target nitro-node-dev -t nitro-node-dev .`.
5. Export the value from the docker: `docker run --rm --entrypoint cat nitro-node-dev /home/user/target/machines/latest/module-root.txt`.

## Upgrades & Governance

### Past upgrades

The metrics include upgrades on the currently used proxy contracts. Historical proxy contracts and changes of such are not included.

- Count of upgrades: 1
- Last upgrade: 3mo 16d ago
- Avg upgrade interval: 2mo 23d

- 2026-06-30 17:40 UTC, deployment of [TimelockController](https://robin.etherscan.io/address/0x560C81fe78FcC276e460524428f1a62057Ca8173#code): transaction [0xee6757ba43dff65e9d0b595e3d538fb039c1d5dc6e9032c4e1de63c51d713dcc](https://robin.etherscan.io/tx/0xee6757ba43dff65e9d0b595e3d538fb039c1d5dc6e9032c4e1de63c51d713dcc), implementations: [0x145046bdd5c4bc72338f60dE5d9707BD73ff1843](https://robin.etherscan.io/address/0x145046bdd5c4bc72338f60dE5d9707BD73ff1843#code)
- 2026-06-30 17:40 UTC, deployment of [TimelockController](https://etherscan.io/address/0xE1e825D15192457d05a251715C3e2Cab0F8CF465#code): transaction [0xb477a23fc6630baa3ecad25b2aaf63d74c843389db8063307762fbc99aea78ba](https://etherscan.io/tx/0xb477a23fc6630baa3ecad25b2aaf63d74c843389db8063307762fbc99aea78ba), implementations: [0x145046bdd5c4bc72338f60dE5d9707BD73ff1843](https://etherscan.io/address/0x145046bdd5c4bc72338f60dE5d9707BD73ff1843#code)
- 2026-04-30 16:52 UTC, deployment of [L1ERC20Gateway](https://etherscan.io/address/0x85001CC4867C5e1C22dA4B79BB8852B9e2a06da0#code): transaction [0x80b3040805a5b37638da6908f951e15306edabbf4773c7b53116daef4f72a04f](https://etherscan.io/tx/0x80b3040805a5b37638da6908f951e15306edabbf4773c7b53116daef4f72a04f), implementations: [0xf43bce5D32742FFC862eA182b0b5544CbDBB0F02](https://etherscan.io/address/0xf43bce5D32742FFC862eA182b0b5544CbDBB0F02#code)
- 2026-04-30 16:52 UTC, deployment of [L1GatewayRouter](https://etherscan.io/address/0x6a2E3a1e16FC29f27Ce61429746D558d656975bB#code): transaction [0x80b3040805a5b37638da6908f951e15306edabbf4773c7b53116daef4f72a04f](https://etherscan.io/tx/0x80b3040805a5b37638da6908f951e15306edabbf4773c7b53116daef4f72a04f), implementations: [0x6525137BfF366fbc0A89E3e5A4d244B5A0090a6D](https://etherscan.io/address/0x6525137BfF366fbc0A89E3e5A4d244B5A0090a6D#code)
- 2026-04-30 16:52 UTC, deployment of [L1WethGateway](https://etherscan.io/address/0xF7e12b9614b509C747ab4423bC4ACF923759Cf1B#code): transaction [0x80b3040805a5b37638da6908f951e15306edabbf4773c7b53116daef4f72a04f](https://etherscan.io/tx/0x80b3040805a5b37638da6908f951e15306edabbf4773c7b53116daef4f72a04f), implementations: [0xa86996bED19547f7dEf22a087dD61b5F9Fb6C684](https://etherscan.io/address/0xa86996bED19547f7dEf22a087dD61b5F9Fb6C684#code)
- 2026-04-30 16:52 UTC, upgrade of [L2UpgradeExecutor](https://robin.etherscan.io/address/0x2A153c6A1B66DBc930a8d7017230ab0253005C09#code): transaction [0x05317cd173ba8e973c7e88aeb7f7e56eb22cf05c12552d4283c993dbb1f56b12](https://robin.etherscan.io/tx/0x05317cd173ba8e973c7e88aeb7f7e56eb22cf05c12552d4283c993dbb1f56b12), implementations: [0xE83b11Faa5693E68388785FecA3595C6805dFb9a](https://robin.etherscan.io/address/0xE83b11Faa5693E68388785FecA3595C6805dFb9a#code) ([diff](https://disco.l2beat.com/diff/robinhood:0x3c3E52bC8C181D06A76e2518bBc655C5BB3Ce7Cd/robinhood:0xE83b11Faa5693E68388785FecA3595C6805dFb9a))
- 2026-04-30 16:52 UTC, deployment of [L2UpgradeExecutor](https://robin.etherscan.io/address/0x2A153c6A1B66DBc930a8d7017230ab0253005C09#code): transaction [0x05317cd173ba8e973c7e88aeb7f7e56eb22cf05c12552d4283c993dbb1f56b12](https://robin.etherscan.io/tx/0x05317cd173ba8e973c7e88aeb7f7e56eb22cf05c12552d4283c993dbb1f56b12), implementations: [0x3c3E52bC8C181D06A76e2518bBc655C5BB3Ce7Cd](https://robin.etherscan.io/address/0x3c3E52bC8C181D06A76e2518bBc655C5BB3Ce7Cd#code)
- 2026-04-30 16:51 UTC, deployment of [RollupProxy](https://etherscan.io/address/0x23A19d23e89166adedbDcB432518AB01e4272D94#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0xAb7A44CE7e66963d2116dCe74AB63eeF88266C82](https://etherscan.io/address/0xAb7A44CE7e66963d2116dCe74AB63eeF88266C82#code), [0xedC23dFC7D1e57EC07eA5ff7419634DbAe08Ed2C](https://etherscan.io/address/0xedC23dFC7D1e57EC07eA5ff7419634DbAe08Ed2C#code)
- 2026-04-30 16:51 UTC, deployment of [EdgeChallengeManager](https://etherscan.io/address/0x6f38FC91105Fc9a43931DcA33450ab3315E3D4Fa#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0xCAaa9332F940362aEAAADD1B0A59c229C4fD8f79](https://etherscan.io/address/0xCAaa9332F940362aEAAADD1B0A59c229C4fD8f79#code)
- 2026-04-30 16:51 UTC, deployment of [SequencerInbox](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0xb015D78fb9B890e96FD3E23819b2C8D9fffA3cC5](https://etherscan.io/address/0xb015D78fb9B890e96FD3E23819b2C8D9fffA3cC5#code)
- 2026-04-30 16:51 UTC, deployment of [Bridge](https://etherscan.io/address/0xDf8755334ce7A73cCF6b581C02eA649AE3E864b3#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0xC678f7B95A7D1F77c6024c0086301D21402854b1](https://etherscan.io/address/0xC678f7B95A7D1F77c6024c0086301D21402854b1#code)
- 2026-04-30 16:51 UTC, deployment of [UpgradeExecutor](https://etherscan.io/address/0x552603b4bc1f5E896AF2854548D6380f45f1B4bf#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0x9149DF379237a935cf0658fE54D2325109493CBb](https://etherscan.io/address/0x9149DF379237a935cf0658fE54D2325109493CBb#code)
- 2026-04-30 16:51 UTC, deployment of [Inbox](https://etherscan.io/address/0x1A07cc4BD17E0118BdB54D70990D2158AbAD7a2D#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0x8D3b93dfFFf4842E7B61FB553b383db2C6BC91c6](https://etherscan.io/address/0x8D3b93dfFFf4842E7B61FB553b383db2C6BC91c6#code)
- 2026-04-30 16:51 UTC, deployment of [Outbox](https://etherscan.io/address/0xf0ce991ea4A0d2400A4AB49b20ae333f6Dce3DE9#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0x396765AEbE540575ef927F769b0d7b89594f931c](https://etherscan.io/address/0x396765AEbE540575ef927F769b0d7b89594f931c#code)
- 2026-04-30 16:51 UTC, deployment of [RollupEventInbox](https://etherscan.io/address/0xc34f4907822d1cDC6aE3038Be22e6f12DEa35bd4#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0x796FeE4adceD1cb47a3e3d1B6925472F8fC8f1f9](https://etherscan.io/address/0x796FeE4adceD1cb47a3e3d1B6925472F8fC8f1f9#code)

## Updates

Each date links the update on the HTML page, which also shows its contract diffs.

### [2026-09-29 08:48 UTC](https://l2beat.com/layer2s/projects/robinhood?update=5dfb7db3) (7 changes)

Routine rediscovery after explorer change

### [2026-09-01 22:18 UTC](https://l2beat.com/layer2s/projects/robinhood?update=0ca66178) (4 changes)

Stopped tracking the tokenized stocks and their AccessControlsRegistry: they are apps on top of the chain, not chain infrastructure. Removes `0xd060…9EEC` and `0xe10b…1b00` from initialAddresses, which also clears the EOA upgrade warning. RollupProxy `arbOsFromWmRoot` now resolves to ArbOS v61; SafeL2 `0x3A0C…7a1C` became verified.

### [2026-08-10 11:03 UTC](https://l2beat.com/layer2s/projects/robinhood?update=70db2222) (1 change)

ArbFilteredTransactionsManager: 3 more transactions were added to the filter list. Remaining entries are config-driven permission updates, not onchain changes.

### [2026-07-30 11:08 UTC](https://l2beat.com/layer2s/projects/robinhood?update=69c32e44) (1 change)

ArbFilteredTransactionsManager recorded one more filtered transaction hash (6087 -> 6088).

### [2026-07-21 09:39 UTC](https://l2beat.com/layer2s/projects/robinhood?update=364d15b2) (3 changes)

Config: add rwa access control contract to the monitoring.

### [2026-07-20 14:11 UTC](https://l2beat.com/layer2s/projects/robinhood?update=324fae10) (1 change)

Recent transaction-filtering increase due to a single wallet being blocked — the
honeypot behind the fake "Robinhood founder seed-phrase leak". Filtered
transactions rose from 278 to 6,086; none have been reversed.

Added the L1 timelock ProxyAdmin (OpenZeppelin v5.0.0) to the ProxyAdmin template.

### [2026-07-14 15:53 UTC](https://l2beat.com/layer2s/projects/robinhood?update=28939e78) (27 changes)

The ArbFilteredTransactionsManager now reports 278 added filtered transaction
hashes, up from 2 in the previous discovery. No filtered transaction hash has
been deleted. Transaction filtering is active: an authorized filterer can register
a transaction hash and make the state transition fail that transaction, including
one force-included from L1.

Governance was restructured on both L1 and L2:

- The single 2-of-3 admin multisig was replaced by a 7-of-8 multisig and a
  7-day timelock. The 7-of-8 multisig remains a direct executor, so upgrades can
  still bypass the timelock delay.
- A separate 6-of-8 multisig can propose and cancel timelock actions.
- The timelock and its admin contracts are now verified on Etherscan and
  Blockscout.

### [2026-07-07 22:01 UTC](https://l2beat.com/layer2s/projects/robinhood?update=ebc0d17e) (36 changes)

ProxyAdmin, Inbox and the eight upgradeable proxies became verified on Etherscan; the permission view now shows the upgrade chain through ProxyAdmin.

### [2026-07-02 10:37 UTC](https://l2beat.com/layer2s/projects/robinhood?update=7e996332) (19 changes)

Initial discovery.

The chain uses ArbOS 61 core contracts, newer builds of standard Orbit contracts.

- **SequencerInbox** — [diff](https://disco.l2beat.com/diff/eth:0x98a58ADAb0f8A66A1BF4544d804bc0475dff32c7/eth:0xb015D78fb9B890e96FD3E23819b2C8D9fffA3cC5)
  Adds an owner-only `setFeeTokenPricer` (inert here: `isUsingFeeToken=false`, `feeTokenPricer=0x0`), a custom-DA header flag (`0x01`, unused — chain posts blobs), and delay-proof paths. No new actors beyond the existing owner/batchPoster.
- **RollupProxy (RollupAdminLogic)** — [diff](https://disco.l2beat.com/diff/eth:0x7FC126FF51183a78C5E0437467f325f661D8Df17/eth:0xAb7A44CE7e66963d2116dCe74AB63eeF88266C82)
  ArbOS 61 admin logic; all setters (allowlist, fee-token, batch-poster mgr, AFK-whitelist) stay owner-gated — covered by the template `owner` permission.
- **RollupProxy (RollupUserLogic)** — [diff](https://disco.l2beat.com/diff/eth:0x6490bA0a60Cc7d3a59C9eeE135D9eeD24553a60d/eth:0xedC23dFC7D1e57EC07eA5ff7419634DbAe08Ed2C)
  ArbOS 61 user logic; BoLD assertion/force-inclusion flow and `getValidators` proposer set unchanged.
- **RollupEventInbox** — [diff](https://disco.l2beat.com/diff/eth:0x6D576E220Cb44C3E8eF75D0EfBeb1Ff041e2E4A5/eth:0x796FeE4adceD1cb47a3e3d1B6925472F8fC8f1f9)
  BoLD event inbox; only `initialize` is rollup-gated, no standing permissions.
- **OneStepProofEntry** — [diff](https://disco.l2beat.com/diff/eth:0x8Faa21891B0b928afEbd5314D1D313f8f7B34DaC/eth:0x5087a6fD526eFD5c6770d94D0c325de0e2A2c44D)
  Proof dispatcher (ArbOS 61 opcode set); immutable constructor-set prover addresses, no mutable state, no permissions.
- **OneStepProver0** — [diff](https://disco.l2beat.com/diff/eth:0x2dCCAbE89cF76132619a9B18e9F9e48E837222b5/eth:0x6fE84aC811EBEcd888Eca93757fEa378Bb03b00c)
  Stateless one-step WASM verifier; ArbOS 61 opcode updates only, no state/permissions.
- **OneStepProverMath** — [diff](https://disco.l2beat.com/diff/eth:0xCf4b98cFF2976E4eb579B9498f398b5bd279A6eD/eth:0x4B15E064d5d55705E89080bDEA4BFe4cF20D6114)
  Stateless math-opcode verifier; ArbOS 61 opcode updates only, no state/permissions.
- **OneStepProverMemory** — [diff](https://disco.l2beat.com/diff/eth:0x1cD76B9C33b2e3b04D7B181399d492B3e49AD7fB/eth:0x665CEA1cA6C36aB701f4C6AE895b156f79C51c35)
  Stateless memory-opcode verifier; ArbOS 61 opcode updates only, no state/permissions.
- **OneStepProverHostIo** — [diff](https://disco.l2beat.com/diff/eth:0x0003A96B27ce73505b43ea1b71a5aB06bec568C4/eth:0xe1aAfAfBde42f043495B39d1a15a58E91c894Fbf)
  Host-io verifier (ArbOS 61 host-io/opcode updates); immutable `customDAValidator` (`0x0` here, so custom-DA proof paths revert), no mutable state, no permissions.

## Operator

### The system has a centralized sequencer

While forcing transaction is open to anyone the system employs a privileged sequencer that has priority for submitting transaction batches and ordering transactions.

**Risks**

- MEV can be extracted if the operator exploits their centralized position and frontruns user transactions.

**References**

- [Sequencer - Arbitrum documentation](https://docs.arbitrum.io/how-arbitrum-works/inside-arbitrum-nitro#the-sequencer)

### Force inclusion can be nullified by transaction filtering

Users can enqueue messages in the L1 delayed inbox and, after the sequencing delay, call forceInclusion on the SequencerInbox to include them. However, the chain runs ArbOS 61 transaction filtering: an authorized filterer can register any transaction hash in the ArbFilteredTransactionsManager precompile (0x00…0074), after which the state transition function forcibly fails that transaction, including one force-included via L1, without delay. Force inclusion is therefore not a reliable censorship escape hatch.

**Risks**

- Users can be censored if the operator registers their transaction hash in the ArbFilteredTransactionsManager precompile, causing the state transition function to fail it even when it is force-included via the L1 delayed inbox.

**References**

- [Transaction screening - Robinhood Chain documentation](https://docs.robinhood.com/chain/differences-from-ethereum/#transaction-screening)
- [Sequencer Isn't Doing Its Job - Arbitrum documentation](https://docs.arbitrum.io/how-arbitrum-works/sequencer#unhappyuncommon-case-sequencer-isnt-doing-its-job)

## Sequencing

### Buffered forced transactions

To force transactions from the host chain, users must first enqueue "delayed" messages in the "delayed" inbox of the Bridge contract. Only authorized Inboxes are allowed to enqueue delayed messages, and the so-called Inbox contract is the one used as the entry point by calling the `sendMessage` or `sendMessageFromOrigin` functions. If the centralized sequencer doesn't process the request within some time bound, users can call the `forceInclusion` function on the SequencerInbox contract to include the message in the canonical chain. The time bound is defined to be the minimum between 4d and the time left in the delay buffer. The delay buffer gets replenished over time and gets consumed every time the sequencer doesn't timely process a message. Only messages processed with a delay greater than 1634y 3mo consume the buffer. The buffer is capped at 1634y 3mo. The replenish rate is currently set at 1m every 20m. Even if the buffer is fully consumed, messages are still allowed to be delayed up to 1634y 3mo.

**References**

- [Sequencer and censorship resistance - Arbitrum documentation](https://docs.arbitrum.io/how-arbitrum-works/sequencer)

## Withdrawals

### Regular messaging

The user initiates L2->L1 messages by submitting a regular transaction on this chain. When the block containing that transaction is settled, the message becomes available for processing on L1. The process of block finalization usually takes several days to complete.

**References**

- [Transaction lifecycle - Arbitrum documentation](https://developer.offchainlabs.com/tx-lifecycle)
- [L2 to L1 Messages - Arbitrum documentation](https://docs.arbitrum.io/how-arbitrum-works/deep-dives/l2-to-l1-messaging)
- [Mainnet for everyone - Arbitrum Blog](https://offchain.medium.com/mainnet-for-everyone-27ce0f67c85e)

### Autonomous exit

Users can (eventually) exit the system by pushing the transaction on L1 and providing the corresponding state root. The only way to prevent such withdrawal is via an upgrade.

## Other considerations

### EVM compatible smart contracts are supported

Arbitrum One uses Nitro technology that allows running fraud proofs by executing EVM code on top of WASM.

**References**

- [Inside Arbitrum Nitro](https://developer.offchainlabs.com/inside-arbitrum-nitro/)

## Permissions

Explore these contracts and permissions in Disco, L2BEAT's contract explorer: https://disco.l2beat.com/ui/p/robinhood

### Ethereum

#### Actors

##### Robinhood Multisig 1

Addresses: [0x7Ae50886c7EA0394613aa7Dcc287a5c9650784b6](https://etherscan.io/address/0x7Ae50886c7EA0394613aa7Dcc287a5c9650784b6)

A Multisig with 7/8 threshold.
- Can upgrade **with no delay**
  - Inbox [via: UpgradeExecutor → ProxyAdmin]
  - RollupProxy [via: UpgradeExecutor]
  - UpgradeExecutor [via: UpgradeExecutor → ProxyAdmin]
  - L1GatewayRouter [via: UpgradeExecutor → ProxyAdmin]
  - EdgeChallengeManager [via: UpgradeExecutor → ProxyAdmin]
  - L1ERC20Gateway [via: UpgradeExecutor → ProxyAdmin]
  - SequencerInbox [via: UpgradeExecutor → ProxyAdmin]
  - RollupEventInbox [via: UpgradeExecutor → ProxyAdmin]
  - Bridge [via: UpgradeExecutor → ProxyAdmin]
  - TimelockController [via: UpgradeExecutor → ProxyAdmin]
  - Outbox [via: UpgradeExecutor → ProxyAdmin]
  - L1WethGateway [via: UpgradeExecutor → ProxyAdmin]
- Can interact with RollupProxy
  - Pause and unpause and set important roles and parameters in the system contracts: Can delegate Sequencer management to a BatchPosterManager address, manage data availability, DACs and the fastConfirmer role, set the Sequencer-only window, introduce an allowList to the bridge and whitelist Inboxes/Outboxes [via: UpgradeExecutor]
- Can interact with TimelockController
  - manage all access control roles [via: UpgradeExecutor]

Participants (8): [0x640BF0B6b8706f35195d6491cbE347c01b967393](https://etherscan.io/address/0x640BF0B6b8706f35195d6491cbE347c01b967393), [0x7957e74a59Af4404f64B454cDfaF08F7047021DD](https://etherscan.io/address/0x7957e74a59Af4404f64B454cDfaF08F7047021DD), [0x0fc5c64074641e677Fb86bCE80303a2eE64344Ac](https://l2beat.com/layer2s/projects/robinhood#Robinhood Multisig 3) (Robinhood Multisig 3), [0x54Fafc2728569b9F6099613482bBc8E47B61E477](https://etherscan.io/address/0x54Fafc2728569b9F6099613482bBc8E47B61E477), [0xb89C85BE593e6A8f7e35AC481b5F75Fc4036f31c](https://etherscan.io/address/0xb89C85BE593e6A8f7e35AC481b5F75Fc4036f31c), [0x29631c2da9Ab1C0Ca1935A463842a9484E34Fa17](https://etherscan.io/address/0x29631c2da9Ab1C0Ca1935A463842a9484E34Fa17), [0x2584fd737d35bE395aa979b18602d0dE65f38b2c](https://etherscan.io/address/0x2584fd737d35bE395aa979b18602d0dE65f38b2c), [0xe94aCAa305ce4DF3862585AD0B8Ed05C8C808d6A](https://etherscan.io/address/0xe94aCAa305ce4DF3862585AD0B8Ed05C8C808d6A)

##### Robinhood Multisig 2

Addresses: [0xbFc2b53552513174A0B006D4799B39871fe0CA1d](https://etherscan.io/address/0xbFc2b53552513174A0B006D4799B39871fe0CA1d)

A Multisig with 6/8 threshold.
- Can upgrade **with 7d delay**
  - Inbox [via: TimelockController with 7d delay → UpgradeExecutor → ProxyAdmin]
  - RollupProxy [via: TimelockController with 7d delay → UpgradeExecutor]
  - UpgradeExecutor [via: TimelockController with 7d delay → UpgradeExecutor → ProxyAdmin]
  - L1GatewayRouter [via: TimelockController with 7d delay → UpgradeExecutor → ProxyAdmin]
  - EdgeChallengeManager [via: TimelockController with 7d delay → UpgradeExecutor → ProxyAdmin]
  - L1ERC20Gateway [via: TimelockController with 7d delay → UpgradeExecutor → ProxyAdmin]
  - SequencerInbox [via: TimelockController with 7d delay → UpgradeExecutor → ProxyAdmin]
  - RollupEventInbox [via: TimelockController with 7d delay → UpgradeExecutor → ProxyAdmin]
  - Bridge [via: TimelockController with 7d delay → UpgradeExecutor → ProxyAdmin]
  - TimelockController [via: TimelockController with 7d delay → UpgradeExecutor → ProxyAdmin]
  - Outbox [via: TimelockController with 7d delay → UpgradeExecutor → ProxyAdmin]
  - L1WethGateway [via: TimelockController with 7d delay → UpgradeExecutor → ProxyAdmin]
- Can interact with RollupProxy
  - Pause and unpause and set important roles and parameters in the system contracts: Can delegate Sequencer management to a BatchPosterManager address, manage data availability, DACs and the fastConfirmer role, set the Sequencer-only window, introduce an allowList to the bridge and whitelist Inboxes/Outboxes **with 7d delay** [via: TimelockController with 7d delay → UpgradeExecutor]
- Can interact with TimelockController
  - cancel queued transactions
  - manage all access control roles **with 7d delay or with 7d delay** [via: TimelockController with 7d delay → UpgradeExecutor - or TimelockController with 7d delay]
  - propose transactions

Participants (8): [0x640BF0B6b8706f35195d6491cbE347c01b967393](https://etherscan.io/address/0x640BF0B6b8706f35195d6491cbE347c01b967393), [0x7957e74a59Af4404f64B454cDfaF08F7047021DD](https://etherscan.io/address/0x7957e74a59Af4404f64B454cDfaF08F7047021DD), [0x0fc5c64074641e677Fb86bCE80303a2eE64344Ac](https://l2beat.com/layer2s/projects/robinhood#Robinhood Multisig 3) (Robinhood Multisig 3), [0x54Fafc2728569b9F6099613482bBc8E47B61E477](https://etherscan.io/address/0x54Fafc2728569b9F6099613482bBc8E47B61E477), [0xb89C85BE593e6A8f7e35AC481b5F75Fc4036f31c](https://etherscan.io/address/0xb89C85BE593e6A8f7e35AC481b5F75Fc4036f31c), [0xd857d3f06D53d1449E6D2b2A6f61ec33c8577bB1](https://etherscan.io/address/0xd857d3f06D53d1449E6D2b2A6f61ec33c8577bB1), [0xC9514ec78905505B4b3947E586bAeEb88E459353](https://etherscan.io/address/0xC9514ec78905505B4b3947E586bAeEb88E459353), [0xe94aCAa305ce4DF3862585AD0B8Ed05C8C808d6A](https://etherscan.io/address/0xe94aCAa305ce4DF3862585AD0B8Ed05C8C808d6A)

##### Robinhood Multisig 3

Addresses: [0x0fc5c64074641e677Fb86bCE80303a2eE64344Ac](https://etherscan.io/address/0x0fc5c64074641e677Fb86bCE80303a2eE64344Ac)

A Multisig with 3/7 threshold.
Member of Robinhood Multisig 1, Robinhood Multisig 2.

Participants (7): [0xBa86e3b54E3Ee00185EccB41ff40FC3d5Ee79ecA](https://etherscan.io/address/0xBa86e3b54E3Ee00185EccB41ff40FC3d5Ee79ecA), [0x582B0cCE0bA332D151998A7cA62Cf12d308b050F](https://etherscan.io/address/0x582B0cCE0bA332D151998A7cA62Cf12d308b050F), [0xFA677559d43856af84E9ceA929E36BF126da4562](https://etherscan.io/address/0xFA677559d43856af84E9ceA929E36BF126da4562), [0x499b56449Fe624Cc984Ec92F64Be01F9619441B4](https://etherscan.io/address/0x499b56449Fe624Cc984Ec92F64Be01F9619441B4), [0x90a0eb0337224f74D694c04648f0Ab8a80E37029](https://etherscan.io/address/0x90a0eb0337224f74D694c04648f0Ab8a80E37029), [0x026F0df4b04a258207337fBB05790F0E1283e526](https://etherscan.io/address/0x026F0df4b04a258207337fBB05790F0E1283e526), [0x9b6488FBa4ed8fD4840F37345311eCCA1B09740C](https://etherscan.io/address/0x9b6488FBa4ed8fD4840F37345311eCCA1B09740C)

##### Robinhood Multisig 4

Addresses: [0x1F3Bdec08A161Ca9e5480feF33A3B2278c2931C5](https://etherscan.io/address/0x1F3Bdec08A161Ca9e5480feF33A3B2278c2931C5)

A Multisig with 2/3 threshold.

Participants (3): [0x29631c2da9Ab1C0Ca1935A463842a9484E34Fa17](https://etherscan.io/address/0x29631c2da9Ab1C0Ca1935A463842a9484E34Fa17), [0x2584fd737d35bE395aa979b18602d0dE65f38b2c](https://etherscan.io/address/0x2584fd737d35bE395aa979b18602d0dE65f38b2c), [0xb89C85BE593e6A8f7e35AC481b5F75Fc4036f31c](https://etherscan.io/address/0xb89C85BE593e6A8f7e35AC481b5F75Fc4036f31c)

##### 2 EOAs

Addresses: [0x992D8d50548fCcCaF11147A9a692c496011C8Aa0](https://etherscan.io/address/0x992D8d50548fCcCaF11147A9a692c496011C8Aa0) (EOA 3), [0xa0A1D8cd6f867a583a39232a477ff231aFD8eC4C](https://etherscan.io/address/0xa0A1D8cd6f867a583a39232a477ff231aFD8eC4C) (EOA 4)

- Can interact with RollupProxy
  - Can propose new state roots (called nodes) and challenge state roots on the host chain

##### EOA 5

Addresses: [0xDaa526086787d9DEbE1D7F3FFdb1fE50cf8687F4](https://etherscan.io/address/0xDaa526086787d9DEbE1D7F3FFdb1fE50cf8687F4)

- Can interact with SequencerInbox
  - Can submit transaction batches or commitments to the SequencerInbox contract on the host chain

### Robinhood Chain

#### Actors

##### Robinhood L2 Multisig 2

Addresses: [0x4C0360aFedD31e53718e4343F95E40b692402462](https://robinhoodchain.blockscout.com/address/0x4C0360aFedD31e53718e4343F95E40b692402462)

A Multisig with 6/8 threshold.
- Can upgrade **with 7d delay**
  - L2UpgradeExecutor [via: TimelockController with 7d delay → L2UpgradeExecutor → ProxyAdmin]
  - TimelockController [via: TimelockController with 7d delay → L2UpgradeExecutor → ProxyAdmin]
- Can interact with L2UpgradeExecutor
  - Can add or remove transaction filterers and change ArbOS configuration on the L2 **with 7d delay** [via: TimelockController with 7d delay → L2UpgradeExecutor]
- Can interact with TimelockController
  - cancel queued transactions
  - manage all access control roles **with 7d delay or with 7d delay** [via: TimelockController with 7d delay → L2UpgradeExecutor - or TimelockController with 7d delay]
  - propose transactions

Participants (8): [0x640BF0B6b8706f35195d6491cbE347c01b967393](https://robinhoodchain.blockscout.com/address/0x640BF0B6b8706f35195d6491cbE347c01b967393), [0x7957e74a59Af4404f64B454cDfaF08F7047021DD](https://robinhoodchain.blockscout.com/address/0x7957e74a59Af4404f64B454cDfaF08F7047021DD), [0x3A0C507Cc7F8785C877359ad49d0476966d17a1C](https://l2beat.com/layer2s/projects/robinhood#Robinhood L2 Multisig 3) (Robinhood L2 Multisig 3), [0x686c4267B9F9868Dff3787CeA38f44868c6DF6eA](https://robinhoodchain.blockscout.com/address/0x686c4267B9F9868Dff3787CeA38f44868c6DF6eA), [0xb89C85BE593e6A8f7e35AC481b5F75Fc4036f31c](https://robinhoodchain.blockscout.com/address/0xb89C85BE593e6A8f7e35AC481b5F75Fc4036f31c), [0xd857d3f06D53d1449E6D2b2A6f61ec33c8577bB1](https://robinhoodchain.blockscout.com/address/0xd857d3f06D53d1449E6D2b2A6f61ec33c8577bB1), [0xC9514ec78905505B4b3947E586bAeEb88E459353](https://robinhoodchain.blockscout.com/address/0xC9514ec78905505B4b3947E586bAeEb88E459353), [0xe94aCAa305ce4DF3862585AD0B8Ed05C8C808d6A](https://robinhoodchain.blockscout.com/address/0xe94aCAa305ce4DF3862585AD0B8Ed05C8C808d6A)

##### Robinhood L2 Multisig 1

Addresses: [0x6b9F63817F1442e40Bb9c3C2207758934C323FdC](https://robinhoodchain.blockscout.com/address/0x6b9F63817F1442e40Bb9c3C2207758934C323FdC)

A Multisig with 7/8 threshold.
- Can upgrade **with no delay**
  - L2UpgradeExecutor [via: L2UpgradeExecutor → ProxyAdmin]
  - TimelockController [via: L2UpgradeExecutor → ProxyAdmin]
- Can interact with L2UpgradeExecutor
  - Can add or remove transaction filterers and change ArbOS configuration on the L2 [via: L2UpgradeExecutor]
- Can interact with TimelockController
  - manage all access control roles [via: L2UpgradeExecutor]

Participants (8): [0x640BF0B6b8706f35195d6491cbE347c01b967393](https://robinhoodchain.blockscout.com/address/0x640BF0B6b8706f35195d6491cbE347c01b967393), [0x7957e74a59Af4404f64B454cDfaF08F7047021DD](https://robinhoodchain.blockscout.com/address/0x7957e74a59Af4404f64B454cDfaF08F7047021DD), [0x3A0C507Cc7F8785C877359ad49d0476966d17a1C](https://l2beat.com/layer2s/projects/robinhood#Robinhood L2 Multisig 3) (Robinhood L2 Multisig 3), [0x686c4267B9F9868Dff3787CeA38f44868c6DF6eA](https://robinhoodchain.blockscout.com/address/0x686c4267B9F9868Dff3787CeA38f44868c6DF6eA), [0xb89C85BE593e6A8f7e35AC481b5F75Fc4036f31c](https://robinhoodchain.blockscout.com/address/0xb89C85BE593e6A8f7e35AC481b5F75Fc4036f31c), [0x29631c2da9Ab1C0Ca1935A463842a9484E34Fa17](https://robinhoodchain.blockscout.com/address/0x29631c2da9Ab1C0Ca1935A463842a9484E34Fa17), [0x2584fd737d35bE395aa979b18602d0dE65f38b2c](https://robinhoodchain.blockscout.com/address/0x2584fd737d35bE395aa979b18602d0dE65f38b2c), [0xe94aCAa305ce4DF3862585AD0B8Ed05C8C808d6A](https://robinhoodchain.blockscout.com/address/0xe94aCAa305ce4DF3862585AD0B8Ed05C8C808d6A)

##### ResourceConstraintManager

Addresses: [0x5Eb36FD3A11f3A123c046E3BF84195BB4f5A2690](https://robinhoodchain.blockscout.com/address/0x5Eb36FD3A11f3A123c046E3BF84195BB4f5A2690)

ArbOS chain owner that can only set the gas pricing constraints of the L2 base fee model within hardcoded bounds. Anyone can remove it from the chain owners after the expiry timestamp.
- Can interact with L2UpgradeExecutor
  - Can add or remove transaction filterers and change ArbOS configuration on the L2

##### Robinhood L2 Multisig 4

Addresses: [0x59f83b75bD225b9c9981B04982639625c88dFb1E](https://robinhoodchain.blockscout.com/address/0x59f83b75bD225b9c9981B04982639625c88dFb1E)

A Multisig with 2/2 threshold.
- Can interact with ResourceConstraintManager
  - set the gas pricing constraints of the L2 base fee model within hardcoded bounds

Participants (2): [0xb89C85BE593e6A8f7e35AC481b5F75Fc4036f31c](https://robinhoodchain.blockscout.com/address/0xb89C85BE593e6A8f7e35AC481b5F75Fc4036f31c), [0x91886E7ecAD146aE89F20c6f05CfdC81e7069ACc](https://robinhoodchain.blockscout.com/address/0x91886E7ecAD146aE89F20c6f05CfdC81e7069ACc)

##### Robinhood L2 Multisig 3

Addresses: [0x3A0C507Cc7F8785C877359ad49d0476966d17a1C](https://robinhoodchain.blockscout.com/address/0x3A0C507Cc7F8785C877359ad49d0476966d17a1C)

A Multisig with 3/7 threshold.
Member of Robinhood L2 Multisig 2, Robinhood L2 Multisig 1.

Participants (7): [0x582B0cCE0bA332D151998A7cA62Cf12d308b050F](https://robinhoodchain.blockscout.com/address/0x582B0cCE0bA332D151998A7cA62Cf12d308b050F), [0xBa86e3b54E3Ee00185EccB41ff40FC3d5Ee79ecA](https://robinhoodchain.blockscout.com/address/0xBa86e3b54E3Ee00185EccB41ff40FC3d5Ee79ecA), [0xFA677559d43856af84E9ceA929E36BF126da4562](https://robinhoodchain.blockscout.com/address/0xFA677559d43856af84E9ceA929E36BF126da4562), [0x499b56449Fe624Cc984Ec92F64Be01F9619441B4](https://robinhoodchain.blockscout.com/address/0x499b56449Fe624Cc984Ec92F64Be01F9619441B4), [0x90a0eb0337224f74D694c04648f0Ab8a80E37029](https://robinhoodchain.blockscout.com/address/0x90a0eb0337224f74D694c04648f0Ab8a80E37029), [0x026F0df4b04a258207337fBB05790F0E1283e526](https://robinhoodchain.blockscout.com/address/0x026F0df4b04a258207337fBB05790F0E1283e526), [0x9b6488FBa4ed8fD4840F37345311eCCA1B09740C](https://robinhoodchain.blockscout.com/address/0x9b6488FBa4ed8fD4840F37345311eCCA1B09740C)

##### EOA 1

Addresses: [0x0000000000000000000000000000000000000000](https://robinhoodchain.blockscout.com/address/0x0000000000000000000000000000000000000000)

- Can upgrade **with 7d delay**
  - L2UpgradeExecutor [via: TimelockController with 7d delay → L2UpgradeExecutor → ProxyAdmin]
  - TimelockController [via: TimelockController with 7d delay → L2UpgradeExecutor → ProxyAdmin]
- Can interact with L2UpgradeExecutor
  - Can add or remove transaction filterers and change ArbOS configuration on the L2 **with 7d delay** [via: TimelockController with 7d delay → L2UpgradeExecutor]
- Can interact with TimelockController
  - execute transactions that are ready
  - manage all access control roles **with 7d delay or with 7d delay** [via: TimelockController with 7d delay → L2UpgradeExecutor - or TimelockController with 7d delay]

##### EOA 2

Addresses: [0x663703B4bC1F5e896Af2854548d6380F45F1C5D0](https://robinhoodchain.blockscout.com/address/0x663703B4bC1F5e896Af2854548d6380F45F1C5D0)

- Can upgrade **with no delay**
  - L2UpgradeExecutor [via: L2UpgradeExecutor → ProxyAdmin]
  - TimelockController [via: L2UpgradeExecutor → ProxyAdmin]
- Can interact with L2UpgradeExecutor
  - Can add or remove transaction filterers and change ArbOS configuration on the L2 [via: L2UpgradeExecutor]
- Can interact with TimelockController
  - manage all access control roles [via: L2UpgradeExecutor]

##### TransactionFilterer

Addresses: [0xebDc18A1F5C42fC25552eA233fAcf4054DF224b7](https://robinhoodchain.blockscout.com/address/0xebDc18A1F5C42fC25552eA233fAcf4054DF224b7)

- Can interact with ArbFilteredTransactionsManager
  - Can register/remove transaction hashes in the ArbFilteredTransactionsManager precompile, causing the state transition function to forcibly fail those transactions, including force-included ones, without delay

## Smart contracts

![A diagram of the smart contract architecture](https://l2beat.com/static/images/architecture/orbit-rollup.7634b065.png)

Explore these contracts and permissions in Disco, L2BEAT's contract explorer: https://disco.l2beat.com/ui/p/robinhood

### Ethereum

#### RollupProxy

Addresses: [0x23A19d23e89166adedbDcB432518AB01e4272D94](https://etherscan.io/address/0x23A19d23e89166adedbDcB432518AB01e4272D94#code), [0xAb7A44CE7e66963d2116dCe74AB63eeF88266C82](https://etherscan.io/address/0xAb7A44CE7e66963d2116dCe74AB63eeF88266C82#code) (Implementation #1 (Upgradable)), [0xedC23dFC7D1e57EC07eA5ff7419634DbAe08Ed2C](https://etherscan.io/address/0xedC23dFC7D1e57EC07eA5ff7419634DbAe08Ed2C#code) (Implementation #2 (Upgradable)), [0x552603b4bc1f5E896AF2854548D6380f45f1B4bf](https://etherscan.io/address/0x552603b4bc1f5E896AF2854548D6380f45f1B4bf#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-04-30 16:51 UTC, deployment of [RollupProxy](https://etherscan.io/address/0x23A19d23e89166adedbDcB432518AB01e4272D94#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0xAb7A44CE7e66963d2116dCe74AB63eeF88266C82](https://etherscan.io/address/0xAb7A44CE7e66963d2116dCe74AB63eeF88266C82#code), [0xedC23dFC7D1e57EC07eA5ff7419634DbAe08Ed2C](https://etherscan.io/address/0xedC23dFC7D1e57EC07eA5ff7419634DbAe08Ed2C#code)

Central contract for the project's configuration like its execution logic hash (`wasmModuleRoot`) and addresses of the other system contracts. Entry point for Proposers creating new assertions (state commitments) and Challengers submitting fraud proofs (In the Orbit stack, these two roles are both called Validators).
- Roles:
  - **admin**: UpgradeExecutor; ultimately Robinhood Multisig 1, Robinhood Multisig 2
  - **getValidators**: EOA 3, EOA 4
  - **owner**: UpgradeExecutor; ultimately Robinhood Multisig 1, Robinhood Multisig 2

Can be upgraded by: Robinhood Multisig 1 with no delay, Robinhood Multisig 2 with 7d delay

#### EdgeChallengeManager

Addresses: [0x6f38FC91105Fc9a43931DcA33450ab3315E3D4Fa](https://etherscan.io/address/0x6f38FC91105Fc9a43931DcA33450ab3315E3D4Fa#code), [0xCAaa9332F940362aEAAADD1B0A59c229C4fD8f79](https://etherscan.io/address/0xCAaa9332F940362aEAAADD1B0A59c229C4fD8f79#code) (Implementation (Upgradable)), [0x1232813BDd40aa9d53066A880dE78a4Be70B90FD](https://etherscan.io/address/0x1232813BDd40aa9d53066A880dE78a4Be70B90FD#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-04-30 16:51 UTC, deployment of [EdgeChallengeManager](https://etherscan.io/address/0x6f38FC91105Fc9a43931DcA33450ab3315E3D4Fa#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0xCAaa9332F940362aEAAADD1B0A59c229C4fD8f79](https://etherscan.io/address/0xCAaa9332F940362aEAAADD1B0A59c229C4fD8f79#code)

Contract that implements the main challenge protocol logic of the fraud proof system.
- Roles:
  - **admin**: ProxyAdmin; ultimately Robinhood Multisig 1, Robinhood Multisig 2

Can be upgraded by: Robinhood Multisig 1 with no delay, Robinhood Multisig 2 with 7d delay

#### SequencerInbox

Addresses: [0xBd0D173EEb87D57A09521c24388a12789F33ba96](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96#code), [0xb015D78fb9B890e96FD3E23819b2C8D9fffA3cC5](https://etherscan.io/address/0xb015D78fb9B890e96FD3E23819b2C8D9fffA3cC5#code) (Implementation (Upgradable)), [0x1232813BDd40aa9d53066A880dE78a4Be70B90FD](https://etherscan.io/address/0x1232813BDd40aa9d53066A880dE78a4Be70B90FD#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-04-30 16:51 UTC, deployment of [SequencerInbox](https://etherscan.io/address/0xBd0D173EEb87D57A09521c24388a12789F33ba96#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0xb015D78fb9B890e96FD3E23819b2C8D9fffA3cC5](https://etherscan.io/address/0xb015D78fb9B890e96FD3E23819b2C8D9fffA3cC5#code)

A sequencer (registered in this contract) can submit transaction batches or commitments here.
- Roles:
  - **admin**: ProxyAdmin; ultimately Robinhood Multisig 1, Robinhood Multisig 2
  - **batchPosters**: EOA 5

Can be upgraded by: Robinhood Multisig 1 with no delay, Robinhood Multisig 2 with 7d delay

#### Bridge (escrow)

Addresses: [0xDf8755334ce7A73cCF6b581C02eA649AE3E864b3](https://etherscan.io/address/0xDf8755334ce7A73cCF6b581C02eA649AE3E864b3#code), [0xC678f7B95A7D1F77c6024c0086301D21402854b1](https://etherscan.io/address/0xC678f7B95A7D1F77c6024c0086301D21402854b1#code) (Implementation (Upgradable)), [0x1232813BDd40aa9d53066A880dE78a4Be70B90FD](https://etherscan.io/address/0x1232813BDd40aa9d53066A880dE78a4Be70B90FD#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-04-30 16:51 UTC, deployment of [Bridge](https://etherscan.io/address/0xDf8755334ce7A73cCF6b581C02eA649AE3E864b3#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0xC678f7B95A7D1F77c6024c0086301D21402854b1](https://etherscan.io/address/0xC678f7B95A7D1F77c6024c0086301D21402854b1#code)

Escrow contract for the project's gas token (can be different from ETH). Keeps a list of allowed Inboxes and Outboxes for canonical bridge messaging.
- Roles:
  - **admin**: ProxyAdmin; ultimately Robinhood Multisig 1, Robinhood Multisig 2

The following tokens are included in the value secured calculation: ETH

Can be upgraded by: Robinhood Multisig 1 with no delay, Robinhood Multisig 2 with 7d delay

#### UpgradeExecutor

Addresses: [0x552603b4bc1f5E896AF2854548D6380f45f1B4bf](https://etherscan.io/address/0x552603b4bc1f5E896AF2854548D6380f45f1B4bf#code), [0x9149DF379237a935cf0658fE54D2325109493CBb](https://etherscan.io/address/0x9149DF379237a935cf0658fE54D2325109493CBb#code) (Implementation (Upgradable)), [0x1232813BDd40aa9d53066A880dE78a4Be70B90FD](https://etherscan.io/address/0x1232813BDd40aa9d53066A880dE78a4Be70B90FD#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-04-30 16:51 UTC, deployment of [UpgradeExecutor](https://etherscan.io/address/0x552603b4bc1f5E896AF2854548D6380f45f1B4bf#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0x9149DF379237a935cf0658fE54D2325109493CBb](https://etherscan.io/address/0x9149DF379237a935cf0658fE54D2325109493CBb#code)

Central contract defining the access control permissions for upgrading the system contract implementations.
- Roles:
  - **admin**: ProxyAdmin; ultimately Robinhood Multisig 1, Robinhood Multisig 2
  - **executors**: Robinhood Multisig 1, TimelockController

Can be upgraded by: Robinhood Multisig 1 with no delay, Robinhood Multisig 2 with 7d delay

#### Inbox

Addresses: [0x1A07cc4BD17E0118BdB54D70990D2158AbAD7a2D](https://etherscan.io/address/0x1A07cc4BD17E0118BdB54D70990D2158AbAD7a2D#code), [0x8D3b93dfFFf4842E7B61FB553b383db2C6BC91c6](https://etherscan.io/address/0x8D3b93dfFFf4842E7B61FB553b383db2C6BC91c6#code) (Implementation (Upgradable)), [0x1232813BDd40aa9d53066A880dE78a4Be70B90FD](https://etherscan.io/address/0x1232813BDd40aa9d53066A880dE78a4Be70B90FD#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-04-30 16:51 UTC, deployment of [Inbox](https://etherscan.io/address/0x1A07cc4BD17E0118BdB54D70990D2158AbAD7a2D#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0x8D3b93dfFFf4842E7B61FB553b383db2C6BC91c6](https://etherscan.io/address/0x8D3b93dfFFf4842E7B61FB553b383db2C6BC91c6#code)

Facilitates sending L1 to L2 messages like depositing ETH, but does not escrow funds.
- Roles:
  - **admin**: ProxyAdmin; ultimately Robinhood Multisig 1, Robinhood Multisig 2

Can be upgraded by: Robinhood Multisig 1 with no delay, Robinhood Multisig 2 with 7d delay

#### L1ERC20Gateway (escrow)

Addresses: [0x85001CC4867C5e1C22dA4B79BB8852B9e2a06da0](https://etherscan.io/address/0x85001CC4867C5e1C22dA4B79BB8852B9e2a06da0#code), [0xf43bce5D32742FFC862eA182b0b5544CbDBB0F02](https://etherscan.io/address/0xf43bce5D32742FFC862eA182b0b5544CbDBB0F02#code) (Implementation (Upgradable)), [0x1232813BDd40aa9d53066A880dE78a4Be70B90FD](https://etherscan.io/address/0x1232813BDd40aa9d53066A880dE78a4Be70B90FD#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-04-30 16:52 UTC, deployment of [L1ERC20Gateway](https://etherscan.io/address/0x85001CC4867C5e1C22dA4B79BB8852B9e2a06da0#code): transaction [0x80b3040805a5b37638da6908f951e15306edabbf4773c7b53116daef4f72a04f](https://etherscan.io/tx/0x80b3040805a5b37638da6908f951e15306edabbf4773c7b53116daef4f72a04f), implementations: [0xf43bce5D32742FFC862eA182b0b5544CbDBB0F02](https://etherscan.io/address/0xf43bce5D32742FFC862eA182b0b5544CbDBB0F02#code)

Escrows deposited ERC-20 assets for the canonical Bridge. Upon depositing, a generic token representation will be minted at the destination. Withdrawals are initiated by the Outbox contract.
- Roles:
  - **admin**: ProxyAdmin; ultimately Robinhood Multisig 1, Robinhood Multisig 2

All supported tokens in this escrow are included in the value secured calculation.

Can be upgraded by: Robinhood Multisig 1 with no delay, Robinhood Multisig 2 with 7d delay

Implementation used in: [AlienX](https://l2beat.com/layer2s/projects/alienx#ERC20Gateway)

#### Outbox

Addresses: [0xf0ce991ea4A0d2400A4AB49b20ae333f6Dce3DE9](https://etherscan.io/address/0xf0ce991ea4A0d2400A4AB49b20ae333f6Dce3DE9#code), [0x396765AEbE540575ef927F769b0d7b89594f931c](https://etherscan.io/address/0x396765AEbE540575ef927F769b0d7b89594f931c#code) (Implementation (Upgradable)), [0x1232813BDd40aa9d53066A880dE78a4Be70B90FD](https://etherscan.io/address/0x1232813BDd40aa9d53066A880dE78a4Be70B90FD#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-04-30 16:51 UTC, deployment of [Outbox](https://etherscan.io/address/0xf0ce991ea4A0d2400A4AB49b20ae333f6Dce3DE9#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0x396765AEbE540575ef927F769b0d7b89594f931c](https://etherscan.io/address/0x396765AEbE540575ef927F769b0d7b89594f931c#code)

Facilitates L2 to L1 contract calls: Messages initiated from L2 (for example withdrawal messages) eventually resolve in execution on L1.
- Roles:
  - **admin**: ProxyAdmin; ultimately Robinhood Multisig 1, Robinhood Multisig 2

Can be upgraded by: Robinhood Multisig 1 with no delay, Robinhood Multisig 2 with 7d delay

#### L1GatewayRouter

Addresses: [0x6a2E3a1e16FC29f27Ce61429746D558d656975bB](https://etherscan.io/address/0x6a2E3a1e16FC29f27Ce61429746D558d656975bB#code), [0x6525137BfF366fbc0A89E3e5A4d244B5A0090a6D](https://etherscan.io/address/0x6525137BfF366fbc0A89E3e5A4d244B5A0090a6D#code) (Implementation (Upgradable)), [0x1232813BDd40aa9d53066A880dE78a4Be70B90FD](https://etherscan.io/address/0x1232813BDd40aa9d53066A880dE78a4Be70B90FD#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-04-30 16:52 UTC, deployment of [L1GatewayRouter](https://etherscan.io/address/0x6a2E3a1e16FC29f27Ce61429746D558d656975bB#code): transaction [0x80b3040805a5b37638da6908f951e15306edabbf4773c7b53116daef4f72a04f](https://etherscan.io/tx/0x80b3040805a5b37638da6908f951e15306edabbf4773c7b53116daef4f72a04f), implementations: [0x6525137BfF366fbc0A89E3e5A4d244B5A0090a6D](https://etherscan.io/address/0x6525137BfF366fbc0A89E3e5A4d244B5A0090a6D#code)

This routing contract maps tokens to the correct escrow (gateway) to be then bridged with canonical messaging.
- Roles:
  - **admin**: ProxyAdmin; ultimately Robinhood Multisig 1, Robinhood Multisig 2

Can be upgraded by: Robinhood Multisig 1 with no delay, Robinhood Multisig 2 with 7d delay

Implementation used in: [AlienX](https://l2beat.com/layer2s/projects/alienx#GatewayRouter)

#### ProxyAdmin (2 instances)

Addresses: [0x1232813BDd40aa9d53066A880dE78a4Be70B90FD](https://etherscan.io/address/0x1232813BDd40aa9d53066A880dE78a4Be70B90FD#code), [0x4e393071053C5d95771b1B716857d65cdf5B1839](https://etherscan.io/address/0x4e393071053C5d95771b1B716857d65cdf5B1839#code)

- Roles:
  - **owner**: UpgradeExecutor

#### OneStepProverMath

Addresses: [0x4B15E064d5d55705E89080bDEA4BFe4cF20D6114](https://etherscan.io/address/0x4B15E064d5d55705E89080bDEA4BFe4cF20D6114#code)

One of the modular contracts used for the last step of a fraud proof, which is simulated inside a WASM virtual machine.

#### OneStepProofEntry

Addresses: [0x5087a6fD526eFD5c6770d94D0c325de0e2A2c44D](https://etherscan.io/address/0x5087a6fD526eFD5c6770d94D0c325de0e2A2c44D#code)

One of the modular contracts used for the last step of a fraud proof, which is simulated inside a WASM virtual machine.

#### OneStepProverMemory

Addresses: [0x665CEA1cA6C36aB701f4C6AE895b156f79C51c35](https://etherscan.io/address/0x665CEA1cA6C36aB701f4C6AE895b156f79C51c35#code)

One of the modular contracts used for the last step of a fraud proof, which is simulated inside a WASM virtual machine.

#### OneStepProver0

Addresses: [0x6fE84aC811EBEcd888Eca93757fEa378Bb03b00c](https://etherscan.io/address/0x6fE84aC811EBEcd888Eca93757fEa378Bb03b00c#code)

One of the modular contracts used for the last step of a fraud proof, which is simulated inside a WASM virtual machine.

#### Wrapped Ether Token

Addresses: [0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2](https://etherscan.io/address/0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2#code)

Implementation used in: [Ronin](https://l2beat.com/layer2s/projects/ronin-network#Wrapped%20Ether%20Token)

#### RollupEventInbox

Addresses: [0xc34f4907822d1cDC6aE3038Be22e6f12DEa35bd4](https://etherscan.io/address/0xc34f4907822d1cDC6aE3038Be22e6f12DEa35bd4#code), [0x796FeE4adceD1cb47a3e3d1B6925472F8fC8f1f9](https://etherscan.io/address/0x796FeE4adceD1cb47a3e3d1B6925472F8fC8f1f9#code) (Implementation (Upgradable)), [0x1232813BDd40aa9d53066A880dE78a4Be70B90FD](https://etherscan.io/address/0x1232813BDd40aa9d53066A880dE78a4Be70B90FD#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-04-30 16:51 UTC, deployment of [RollupEventInbox](https://etherscan.io/address/0xc34f4907822d1cDC6aE3038Be22e6f12DEa35bd4#code): transaction [0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8](https://etherscan.io/tx/0x7982d3d9da29185af78f7802cd2bdb04bdfb702766bb583c3b2804d762dc1fa8), implementations: [0x796FeE4adceD1cb47a3e3d1B6925472F8fC8f1f9](https://etherscan.io/address/0x796FeE4adceD1cb47a3e3d1B6925472F8fC8f1f9#code)

Helper contract sending configuration data over the bridge during the systems initialization.
- Roles:
  - **admin**: ProxyAdmin; ultimately Robinhood Multisig 1, Robinhood Multisig 2

Can be upgraded by: Robinhood Multisig 1 with no delay, Robinhood Multisig 2 with 7d delay

#### OneStepProverHostIo

Addresses: [0xe1aAfAfBde42f043495B39d1a15a58E91c894Fbf](https://etherscan.io/address/0xe1aAfAfBde42f043495B39d1a15a58E91c894Fbf#code)

One of the modular contracts used for the last step of a fraud proof, which is simulated inside a WASM virtual machine.

#### TimelockController

Addresses: [0xE1e825D15192457d05a251715C3e2Cab0F8CF465](https://etherscan.io/address/0xE1e825D15192457d05a251715C3e2Cab0F8CF465#code), [0x145046bdd5c4bc72338f60dE5d9707BD73ff1843](https://etherscan.io/address/0x145046bdd5c4bc72338f60dE5d9707BD73ff1843#code) (Implementation (Upgradable)), [0x4e393071053C5d95771b1B716857d65cdf5B1839](https://etherscan.io/address/0x4e393071053C5d95771b1B716857d65cdf5B1839#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-06-30 17:40 UTC, deployment of [TimelockController](https://etherscan.io/address/0xE1e825D15192457d05a251715C3e2Cab0F8CF465#code): transaction [0xb477a23fc6630baa3ecad25b2aaf63d74c843389db8063307762fbc99aea78ba](https://etherscan.io/tx/0xb477a23fc6630baa3ecad25b2aaf63d74c843389db8063307762fbc99aea78ba), implementations: [0x145046bdd5c4bc72338f60dE5d9707BD73ff1843](https://etherscan.io/address/0x145046bdd5c4bc72338f60dE5d9707BD73ff1843#code)

A timelock with access control. The current minimum delay is 7d.
- Roles:
  - **admin**: ProxyAdmin; ultimately Robinhood Multisig 1, Robinhood Multisig 2
  - **canceller**: Robinhood Multisig 2
  - **defaultAdmin**: TimelockController, UpgradeExecutor; ultimately Robinhood Multisig 1, Robinhood Multisig 2
  - **proposer**: Robinhood Multisig 2

Can be upgraded by: Robinhood Multisig 1 with no delay, Robinhood Multisig 2 with 7d delay

#### L1WethGateway (escrow)

Addresses: [0xF7e12b9614b509C747ab4423bC4ACF923759Cf1B](https://etherscan.io/address/0xF7e12b9614b509C747ab4423bC4ACF923759Cf1B#code), [0xa86996bED19547f7dEf22a087dD61b5F9Fb6C684](https://etherscan.io/address/0xa86996bED19547f7dEf22a087dD61b5F9Fb6C684#code) (Implementation (Upgradable)), [0x1232813BDd40aa9d53066A880dE78a4Be70B90FD](https://etherscan.io/address/0x1232813BDd40aa9d53066A880dE78a4Be70B90FD#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-04-30 16:52 UTC, deployment of [L1WethGateway](https://etherscan.io/address/0xF7e12b9614b509C747ab4423bC4ACF923759Cf1B#code): transaction [0x80b3040805a5b37638da6908f951e15306edabbf4773c7b53116daef4f72a04f](https://etherscan.io/tx/0x80b3040805a5b37638da6908f951e15306edabbf4773c7b53116daef4f72a04f), implementations: [0xa86996bED19547f7dEf22a087dD61b5F9Fb6C684](https://etherscan.io/address/0xa86996bED19547f7dEf22a087dD61b5F9Fb6C684#code)

- Roles:
  - **admin**: ProxyAdmin; ultimately Robinhood Multisig 1, Robinhood Multisig 2

All supported tokens in this escrow are included in the value secured calculation.

Can be upgraded by: Robinhood Multisig 1 with no delay, Robinhood Multisig 2 with 7d delay

### Robinhood Chain

#### L2UpgradeExecutor

Addresses: [0x2A153c6A1B66DBc930a8d7017230ab0253005C09](https://robin.etherscan.io/address/0x2A153c6A1B66DBc930a8d7017230ab0253005C09#code), [0x3c3E52bC8C181D06A76e2518bBc655C5BB3Ce7Cd](https://robin.etherscan.io/address/0x3c3E52bC8C181D06A76e2518bBc655C5BB3Ce7Cd#code) (Implementation (Upgradable)), [0xa3Acd31AFb851B4eB9DAD00F5204c01D924267dF](https://robin.etherscan.io/address/0xa3Acd31AFb851B4eB9DAD00F5204c01D924267dF#code) (Admin)

**Past upgrades** (Count of upgrades: 1, Last upgrade: 5mo 17d ago, Avg upgrade interval: 2mo 23d)

- 2026-04-30 16:52 UTC, upgrade of [L2UpgradeExecutor](https://robin.etherscan.io/address/0x2A153c6A1B66DBc930a8d7017230ab0253005C09#code): transaction [0x05317cd173ba8e973c7e88aeb7f7e56eb22cf05c12552d4283c993dbb1f56b12](https://robin.etherscan.io/tx/0x05317cd173ba8e973c7e88aeb7f7e56eb22cf05c12552d4283c993dbb1f56b12), implementations: [0xE83b11Faa5693E68388785FecA3595C6805dFb9a](https://robin.etherscan.io/address/0xE83b11Faa5693E68388785FecA3595C6805dFb9a#code) ([diff](https://disco.l2beat.com/diff/robinhood:0x3c3E52bC8C181D06A76e2518bBc655C5BB3Ce7Cd/robinhood:0xE83b11Faa5693E68388785FecA3595C6805dFb9a))
- 2026-04-30 16:52 UTC, deployment of [L2UpgradeExecutor](https://robin.etherscan.io/address/0x2A153c6A1B66DBc930a8d7017230ab0253005C09#code): transaction [0x05317cd173ba8e973c7e88aeb7f7e56eb22cf05c12552d4283c993dbb1f56b12](https://robin.etherscan.io/tx/0x05317cd173ba8e973c7e88aeb7f7e56eb22cf05c12552d4283c993dbb1f56b12), implementations: [0x3c3E52bC8C181D06A76e2518bBc655C5BB3Ce7Cd](https://robin.etherscan.io/address/0x3c3E52bC8C181D06A76e2518bBc655C5BB3Ce7Cd#code)

ArbOS chain owner (UpgradeExecutor). Manages the ArbOwner chain-owner set and the transaction-filterer set, and can upgrade ArbOS configuration without delay.
- Roles:
  - **admin**: ProxyAdmin; ultimately EOA 1, EOA 2, Robinhood L2 Multisig 1, Robinhood L2 Multisig 2
  - **chainOwners**: L2UpgradeExecutor, ResourceConstraintManager; ultimately EOA 1, EOA 2, Robinhood L2 Multisig 1, Robinhood L2 Multisig 2
  - **executors**: EOA 2, Robinhood L2 Multisig 1, TimelockController

Can be upgraded by: EOA 1 with 7d delay, Robinhood L2 Multisig 2 with 7d delay, EOA 2 with no delay, Robinhood L2 Multisig 1 with no delay

#### ArbFilteredTransactionsManager

Addresses: [0x0000000000000000000000000000000000000074](https://robin.etherscan.io/address/0x0000000000000000000000000000000000000074#code)

ArbOS 61 transaction-filtering precompile. An authorized filterer registers tx hashes here; the state transition function then forcibly fails those transactions, including force-included ones, without delay.
- Roles:
  - **transactionFilterers**: TransactionFilterer

**References**

- [Source Code](https://github.com/OffchainLabs/nitro/blob/v3.11.0/precompiles/ArbFilteredTransactionsManager.go)

#### TimelockController

Addresses: [0x560C81fe78FcC276e460524428f1a62057Ca8173](https://robin.etherscan.io/address/0x560C81fe78FcC276e460524428f1a62057Ca8173#code), [0x145046bdd5c4bc72338f60dE5d9707BD73ff1843](https://robin.etherscan.io/address/0x145046bdd5c4bc72338f60dE5d9707BD73ff1843#code) (Implementation (Upgradable)), [0x672Da8B43058D1bC78956d71d9A208E168E2a3EF](https://robin.etherscan.io/address/0x672Da8B43058D1bC78956d71d9A208E168E2a3EF#code) (Admin)

**Past upgrades** (Count of upgrades: No upgrades, Last upgrade: N/A, Avg upgrade interval: N/A)

- 2026-06-30 17:40 UTC, deployment of [TimelockController](https://robin.etherscan.io/address/0x560C81fe78FcC276e460524428f1a62057Ca8173#code): transaction [0xee6757ba43dff65e9d0b595e3d538fb039c1d5dc6e9032c4e1de63c51d713dcc](https://robin.etherscan.io/tx/0xee6757ba43dff65e9d0b595e3d538fb039c1d5dc6e9032c4e1de63c51d713dcc), implementations: [0x145046bdd5c4bc72338f60dE5d9707BD73ff1843](https://robin.etherscan.io/address/0x145046bdd5c4bc72338f60dE5d9707BD73ff1843#code)

A timelock with access control. The current minimum delay is 7d.
- Roles:
  - **admin**: ProxyAdmin; ultimately EOA 1, EOA 2, Robinhood L2 Multisig 1, Robinhood L2 Multisig 2
  - **canceller**: Robinhood L2 Multisig 2
  - **defaultAdmin**: L2UpgradeExecutor, TimelockController; ultimately EOA 1, EOA 2, Robinhood L2 Multisig 1, Robinhood L2 Multisig 2
  - **executor**: EOA 1
  - **proposer**: Robinhood L2 Multisig 2

Can be upgraded by: EOA 1 with 7d delay, Robinhood L2 Multisig 2 with 7d delay, EOA 2 with no delay, Robinhood L2 Multisig 1 with no delay

#### ProxyAdmin (2 instances)

Addresses: [0x672Da8B43058D1bC78956d71d9A208E168E2a3EF](https://robin.etherscan.io/address/0x672Da8B43058D1bC78956d71d9A208E168E2a3EF#code), [0xa3Acd31AFb851B4eB9DAD00F5204c01D924267dF](https://robin.etherscan.io/address/0xa3Acd31AFb851B4eB9DAD00F5204c01D924267dF#code)

- Roles:
  - **owner**: L2UpgradeExecutor

The current deployment carries some associated risks:

- Funds can be stolen if a contract receives a malicious code upgrade. There is no delay on code upgrades (CRITICAL).

### Program Hashes

#### ArbOS wasmModuleRoot v61

A commitment to the exact WASM binary version used for Orbit stack optimistic dispute games.

- Hash: `0xc10cd7ec6acaf1c441a3f6bd0900ad20f15855ba775a96f1939118cbc629dc97`
- Repository: https://github.com/OffchainLabs/nitro/tree/consensus-v61/arbos
- Verification: successful
- Used in: [Arbitrum One](https://l2beat.com/layer2s/projects/arbitrum), [Robinhood Chain](https://l2beat.com/layer2s/projects/robinhood), [Arbitrum Nova](https://l2beat.com/layer2s/projects/nova)

##### Verification steps

Even though the program is compiled in docker for reproducibility reasons, it gives the correct results only on linux OS. Steps below were done on Ubuntu 22.04 OS. The steps below consume ~95 GiB disk space.

1. Install docker [https://docs.docker.com/get-started/get-docker/](https://docs.docker.com/get-started/get-docker/).
2. Checkout the correct branch in [nitro](https://github.com/OffchainLabs/nitro) repo: `git checkout consensus-v61` . Commit hash should be `dfab1dea5c8d2c5089eb26d22ad6239bb78cfa5d`.
3. Update git submodules `git submodule update --init --recursive --force`.
4. Fix a dependency on a private repo in `Dockerfile`: replace line `RUN --mount=type=secret,id=gh_token,required=false ./download-machine.sh consensus-v60-rc.3 0xeadc910d36a0eab43a3dd7acb1a3513885e333785689c7cf750b9949c5bb7227 OffchainLabs/nitro-private` with `RUN ./download-machine.sh consensus-v60-rc.5 0x7a9e6a77354888257a9989ce0b6bb39df5fedf222d453932933fdf7a489cbb57`.
4. Generate wasm module root in docker: `docker buildx build --target nitro-node-dev -t nitro-node-dev .`.
5. Export the value from the docker: `docker run --rm --entrypoint cat nitro-node-dev /home/user/target/machines/latest/module-root.txt`.