# Base Chain

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

## Summary

**Warning:** There are impactful changes and part of the information might be outdated.

- Total Value Secured: $16.36 B (+0.67% compared to seven days ago; canonically bridged $3.09 B, natively minted $8.07 B, externally bridged $5.19 B; 31.7% with additional trust assumptions compared to the tokens involved and the Stage assigned to the project's canonical messaging bridge)
- Past day UOPS: 127.55 (+0.90% compared to seven days ago)
- Stage: Stage 1
- Gas token: ETH
- Type: Optimistic Rollup
- Purpose: Universal
- Host chain: Ethereum
- Chain ID: 8453

### Risks

- Sequencer failure: Self sequence (sentiment: good)
- State validation: Fraud proofs (1R, ZK) (sentiment: good)
- Data availability: Onchain (sentiment: good)
- Exit window: None (sentiment: bad)
- Proposer failure: Self propose (sentiment: good)

### About

Base is an Optimistic Rollup built with the OP Stack. It offers a low-cost and builder-friendly way for anyone, anywhere, to build onchain.

## Value Secured

Shown as an interactive chart or widget on [the HTML page](https://l2beat.com/layer2s/projects/base#tvs).

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

## Volume and flows

Shown as an interactive chart or widget on [the HTML page](https://l2beat.com/layer2s/projects/base#interop-flows).

## Activity

Shown as an interactive chart or widget on [the HTML page](https://l2beat.com/layer2s/projects/base#activity).

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

## Onchain costs

Shown as an interactive chart or widget on [the HTML page](https://l2beat.com/layer2s/projects/base#onchain-costs).

## Data posted

Shown as an interactive chart or widget on [the HTML page](https://l2beat.com/layer2s/projects/base#data-posted).

## Liveness

Shown as an interactive chart or widget on [the HTML page](https://l2beat.com/layer2s/projects/base#liveness).

## Milestones & Incidents

- 2026-05-26: [Base Azul: multi-proof](https://blog.base.dev/introducing-base-azul). Base activates the multiproof system combining TEE attestations and SP1 ZK proofs.
- 2026-03-04: [Base leaves the Superchain](https://blog.base.dev/next-chapter-for-base-chain-1). Base decouples from Optimism Superchain governance with its own upgrade path.
- 2025-08-05 (incident): [Base halts block production for 33mins](https://status.base.org/incidents/kdq3t8s13gfs).
- 2025-04-29: [Base achieves Stage 1](https://base.mirror.xyz/tWDMlGp48fF0MeADcLQruUBq1Qxkou4O5x3ax8Rm3jA). Through an upgrade in their governance process and a Security Council, Base is now stage 1.
- 2024-10-30: [Fault proofs!](https://base.mirror.xyz/eOsedW4tm8MU5OhdGK107A9wsn-aU7MAb8f3edgX5Tk). Base upgrades to OP stack fault proofs for state proving.
- 2024-03-14: [Base starts using blobs](https://twitter.com/Optimism/status/1768235284494450922). Base starts publishing data to blobs.
- 2023-09-05 (incident): [Chain stall](https://status.base.org/incidents/n3q0q4z24b7h). Due to an RPC issue, the sequencer stops producing blocks for ~30 minutes.
- 2023-07-13: [Mainnet Launch](https://base.mirror.xyz/hwNwqXHVoLlO8s4DZppog4DfGvM34tigaDjOWuEJQfY). Base is live on mainnet.

## Risk summary

### Funds can be stolen if

1. a contract receives a malicious code upgrade. Upgrades must be approved by 2 parties: the Base Coordinator Multisig and the Base Security Council. There is no delay on upgrades.

## Risk analysis

### Sequencer failure

Self sequence (sentiment: good)

In the event of a sequencer failure, users can force transactions to be included in the project's chain by sending them to L1. There can be up to a 12h delay on this operation.

### State validation

Fraud proofs (1R, ZK) (sentiment: good)

Fraud proofs allow actors watching the chain to prove that the state is incorrect. Single round proofs (1R) prove the validity of a state proposal, only requiring a single transaction to resolve. A fault proof eliminates a state proposal by proving that any intermediate state transition in the proposal results in a different state root. For either, a ZK proof is used.

### 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. Upgrades need to be approved by 2 parties: the Base Coordinator Multisig and the Base Security Council.

### Proposer failure

Self propose (sentiment: good)

Anyone can be a Proposer and propose new roots to the L1 bridge.

## Stage

Base Chain is a Stage 1 Optimistic Rollup.

### Stage 0

- [x] A complete and functional proof system is deployed.
- [x] There are at least 5 external actors who can submit fraud proofs.
- [x] The project calls itself a rollup.
- [x] State roots are posted to Ethereum L1.
- [x] Inputs for the state transition function are posted to Ethereum L1.
- [x] 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. [View code](https://github.com/base-org/node)

### Stage 1

- [x] Principle: Compromising ≥75% of the Security Council is 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.
- [x] Users are able to exit without the help of the permissioned operators.
- [x] In case of an unwanted upgrade by actors more centralized than a Security Council, users have at least 7d to exit.
- [x] The Security Council is properly set up.
- [x] The proof system meets the minimum trusted setup requirements defined in the L2BEAT [trusted setup assessment framework](https://forum.l2beat.com/t/the-trusted-setups-framework-for-zk-catalog/381).
- [x] Prover source code is published. [View code](https://github.com/succinctlabs/op-succinct)
- [x] Onchain verifiers' smart contracts can be independently regenerated from the verifier source code.
- [x] The sources of all programs used are public and program hashes can be independently regenerated.

### Stage 2

- [x] Fraud proof submission is open to everyone.
- [ ] Upgrades unrelated to onchain provable bugs provide less than 30d to exit.
- [ ] The Security Council's actions are not confined to onchain provable bugs.

## 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**

- [Derivation: Batch submission - OP Mainnet specs](https://github.com/ethereum-optimism/specs/blob/main/specs/protocol/derivation.md#batch-submission)
- [BatchInbox - address](https://etherscan.io/address/0xFf00000000000000000000000000000000008453#code)
- [OptimismPortal2.sol - source code, depositTransaction function](https://etherscan.io/address/0x66d94eE8F529b683ED6013729784e8bb44697A64#code)

## State derivation

### Node software

The rollup node is composed of two software components: [op-node](https://github.com/ethereum-optimism/optimism/tree/develop/op-node), implementing consensus related logic, and [op-geth](https://github.com/ethereum-optimism/op-geth), implementing execution logic. The configuration file can be found [here](https://github.com/ethereum-optimism/superchain-registry/blob/main/superchain/configs/mainnet/base.toml).

### Compression scheme

Data batches are compressed using the [zlib](https://github.com/madler/zlib) algorithm with best compression level.

### Genesis state

The genesis file can be found [here](https://raw.githubusercontent.com/base-org/node/refs/tags/v0.8.4/mainnet/genesis-l2.json).

### Data format

The format specification of Sequencer's data batches can be found [here](https://optimism.io/blog/here-s-how-you-can-reproduce-op-mainnet-s-migration-to-bedrock).

## State validation

### State root proposals

State roots are proposed by calling `DisputeGameFactory.create` with the AggregateVerifier game type, posting a bond of 0.05 ETH. Each proposal must include an initial proof (TEE attestation or ZK proof) over the range of 600 L2 blocks split into sub-ranges of 30 blocks. With a single proof, the game resolves after 5d; if both proof arms commit, the window collapses to 1d.

### Challenges

Any party that produces a valid ZK proof of an incorrect intermediate root can call `AggregateVerifier.challenge`, contradicting a TEE-only proposal. The challenger's proof is verified onchain via the SP1 verifier gateway. If the challenge stands until the resolution window closes, the original proposer's bond is awarded to the challenger and the game resolves CHALLENGER_WINS. Soundness contradictions within a single proof arm are caught by `AggregateVerifier.nullify`, which permanently disables that arm's verifier contract for all games.

## Upgrades & Governance

All contracts are upgradable by a `ProxyAdmin` contract controlled by a nested 2/2 `Base Governance Multisig` composed of the `Base Coordinator Multisig` and the `Base Security Council`. Upgrades require approval from both parties. There is no delay on upgrades. The Guardian role for the SuperchainConfig is assigned to the Base Governance Multisig, which can pause and unpause withdrawals. `Base Multisig 1` serves as Incident Responder and can pause withdrawals but cannot unpause or extend pauses. Each pause automatically expires after 3 months if not extended by the Guardian. The single Sequencer actor can be modified by `Base Multisig 1` via the SystemConfig contract. The Base Governance multisig can also recover dispute bonds in case of bugs that would distribute them incorrectly.

State validation runs through the `AggregateVerifier` game type (621), which accepts either an AWS Nitro TEE attestation or an SP1 ZK proof. The TEE prover allowlist in the `TEEProverRegistry` is managed solely by the `Base Coordinator Multisig` (without Base Security Council approval), and a separate Manager EOA can register or deregister enclave signers. The ZK arm routes through a Base-owned SP1 verifier gateway; the Base Governance Multisig can add or freeze verifier routes. The Base Governance Multisig can swap the AggregateVerifier implementation, change the respected game type, blacklist individual games, or retire all in-flight games via the AnchorStateRegistry.

## Updates

Shown as an interactive chart or widget on [the HTML page](https://l2beat.com/layer2s/projects/base#updates).

## Operator

### Users can force any transaction

Because the state of the system is based on transactions submitted on the underlying host chain and anyone can submit their transactions there it allows the users to circumvent censorship by interacting with the smart contract on the host chain directly.

**References**

- [Sequencing Window - OP Mainnet Specs](https://github.com/ethereum-optimism/optimism/blob/51eeb76efeb32b3df3e978f311188aa29f5e3e94/specs/glossary.md#sequencing-window)
- [OptimismPortal2.sol - source code, depositTransaction function](https://etherscan.io/address/0x66d94eE8F529b683ED6013729784e8bb44697A64#code)

## Sequencing

### Transactions are ordered by a centralized sequencer

Base uses a single centralized sequencer for fast confirmations. Users can bypass it with one Ethereum transaction to the OptimismPortal. Base nodes derive the deposited transaction from Ethereum, including it after at most one sequencing window.

#### Censorship resistance

The centralized sequencer provides no real-time censorship resistance. The Ethereum deposit path provides eventual censorship resistance, assuming the deposit is included on Ethereum.

**References**

- [Base documentation - Flashblocks](https://docs.base.org/base-chain/flashblocks/faq)
- [Base engineering - Sequencer architecture](https://blog.base.dev/flashblocks-deep-dive)
- [Base source code - Mainnet chain configuration](https://github.com/base/base/blob/5761d838af8ae52e4904a74af2f3d8b490f56fec/crates/common/chains/src/config.rs#L402-L409)
- [Base Beryl - Reduced withdrawal delay](https://blog.base.dev/introducing-base-beryl)
- [OptimismPortal2 - source code](https://etherscan.io/address/0x66d94eE8F529b683ED6013729784e8bb44697A64#code)
- [AggregateVerifier - source code](https://etherscan.io/address/0xeE303bA054c5F1E14A8EF87f1C7E285af45A1ba2#code)

## Withdrawals

### Forced messaging

If the user experiences censorship from the operator with regular L2->L1 messaging they can submit their messages directly on L1. The system is then obliged to service this request or halt all messages, including forced withdrawals from L1 and regular messages initiated on L2. Once the force operation is submitted and if the request is serviced, the operation follows the flow of a regular message.

**References**

- [Forced withdrawal from an OP Stack blockchain](https://docs.optimism.io/stack/transactions/forced-transaction)

## Other considerations

### EVM compatible smart contracts are supported

OP stack chains are pursuing the EVM Equivalence model. No changes to smart contracts are required regardless of the language they are written in, i.e. anything deployed on L1 can be deployed on L2.

**References**

- [Introducing EVM Equivalence](https://medium.com/ethereum-optimism/introducing-evm-equivalence-5c2021deb306)

## Permissions

### Ethereum

#### Actors

##### Base Governance Multisig

Addresses: [0x7bB41C3008B3f03FE483B28b8DB90e19Cf07595c](https://etherscan.io/address/0x7bB41C3008B3f03FE483B28b8DB90e19Cf07595c)

A Multisig with 2/2 threshold. 
* Can upgrade **with no delay**
  * OptimismMintableERC20Factory [via: ProxyAdmin]
  * TEEProverRegistry [via: ProxyAdmin]
  * DelayedWETH [via: ProxyAdmin]
  * L1StandardBridge [via: ProxyAdmin]
  * DisputeGameFactory [via: ProxyAdmin]
  * OptimismPortal2 [via: ProxyAdmin]
  * L1ERC721Bridge [via: ProxyAdmin]
  * DelayedWETH [via: ProxyAdmin]
  * SystemConfig [via: ProxyAdmin]
  * L1CrossDomainMessenger [via: ProxyAdmin]
  * AnchorStateRegistry [via: ProxyAdmin]
  * SuperchainConfig [via: ProxyAdmin]
  * DelayedWETH [via: ProxyAdmin]
* Can interact with AddressManager
  * set and change address mappings [via: ProxyAdmin]
* Can interact with SuperchainConfig
  * Allowed to pause withdrawals. In op stack systems with a proof system, the Guardian can also blacklist dispute games and set the respected game type (permissioned / permissionless) 
* Can interact with SP1VerifierGateway
  * affect the liveness and safety of the gateway - can transfer ownership, add and freeze verifier routes 

##### Base Multisig 1

Addresses: [0x14536667Cd30e52C0b458BaACcB9faDA7046E056](https://etherscan.io/address/0x14536667Cd30e52C0b458BaACcB9faDA7046E056)

A Multisig with 3/12 threshold. 
* Can interact with SystemConfig
  * it can update the preconfer address, the batch submitter (Sequencer) address and the gas configuration of the system 
* Can interact with SuperchainConfig
  * can pause for up to 3mo 1d, but cannot unpause or extend pauses 

##### Safe

Addresses: [0x2E5bcc9959dB5F5016F830E47943b07242CB2609](https://etherscan.io/address/0x2E5bcc9959dB5F5016F830E47943b07242CB2609)

A Multisig with 3/5 threshold. 
* Can interact with TimelockController
  * cancel queued transactions 
  * execute transactions that are ready 
  * manage all access control roles **with 3d delay** [via: TimelockController with 3d delay]
  * propose transactions 
* Can interact with RiscZeroVerifierEmergencyStop
  * pause the verifier 
* Can interact with RiscZeroVerifierEmergencyStop
  * pause the verifier 
* Can interact with RiscZeroVerifierEmergencyStop
  * pause the verifier 
* Can interact with RiscZeroVerifierRouter
  * add/remove verifiers and the selectors they are mapped to **with 3d delay** [via: TimelockController with 3d delay]
* Can interact with RiscZeroVerifierEmergencyStop
  * pause the verifier 
* Can interact with RiscZeroVerifierEmergencyStop
  * pause the verifier 

##### Base Security Council

Addresses: [0x20AcF55A3DCfe07fC4cecaCFa1628F788EC8A4Dd](https://etherscan.io/address/0x20AcF55A3DCfe07fC4cecaCFa1628F788EC8A4Dd)

A Multisig with 8/11 threshold. 
Member of Base Governance Multisig.


**References**

- [Security Council members - Base Docs](https://docs.base.org/chain/security-council)

##### Base Coordinator Multisig

Addresses: [0x9855054731540A48b28990B63DcF4f33d8AE46A1](https://etherscan.io/address/0x9855054731540A48b28990B63DcF4f33d8AE46A1)

A Multisig with 3/6 threshold. 
Member of Base Governance Multisig.


##### EOA 1

Addresses: [0x5050F69a9786F081509234F1a7F4684b5E5b76C9](https://etherscan.io/address/0x5050F69a9786F081509234F1a7F4684b5E5b76C9)

* Can interact with SystemConfig
  * Allowed to commit transactions from the current layer to the host chain 

##### EOA 3

Addresses: [0xF616A4f81857CFEe54A4A049Ec187172574bd412](https://etherscan.io/address/0xF616A4f81857CFEe54A4A049Ec187172574bd412)

* Can interact with RiscZeroVerifierEmergencyStop
  * pause the verifier 

### Base Chain

#### Actors

##### Base Governance Multisig - L2 Alias

Addresses: [0x8cC51c3008b3f03Fe483B28B8Db90e19cF076a6d](https://basescan.org/address/0x8cC51c3008b3f03Fe483B28B8Db90e19cF076a6d)

* Can upgrade **with no delay**
  * L2CrossDomainMessenger [via: ProxyAdmin]
  * L2StandardBridge [via: ProxyAdmin]
  * SequencerFeeVault [via: ProxyAdmin]
  * OptimismMintableERC20Factory [via: ProxyAdmin]
  * L1BlockNumber [via: ProxyAdmin]
  * L2ERC721Bridge [via: ProxyAdmin]
  * L1Block [via: ProxyAdmin]
  * L2ToL1MessagePasser [via: ProxyAdmin]
  * OptimismMintableERC721Factory [via: ProxyAdmin]
  * ProxyAdmin [via: ProxyAdmin]
  * BaseFeeVault [via: ProxyAdmin]
  * L1FeeVault [via: ProxyAdmin]
  * SchemaRegistry [via: ProxyAdmin]
  * EAS [via: ProxyAdmin]

##### EOA 2

Addresses: [0xa966054731540a48b28990b63Dcf4f33d8aE57B2](https://basescan.org/address/0xa966054731540a48b28990b63Dcf4f33d8aE57B2)

* Can upgrade **with no delay**
  * FeeDisburser 

## Smart contracts

### Ethereum

#### RiscZeroGroth16Verifier

Addresses: [0x20ff7C2Cf391a5F096A2Cc181cb41916680f8E97](https://etherscan.io/address/0x20ff7C2Cf391a5F096A2Cc181cb41916680f8E97#code)

Verifier contract for RISC Zero Groth16 proofs (version 2.0.0-rc.3).


#### RiscZeroGroth16Verifier

Addresses: [0x2a098988600d87650Fb061FfAff08B97149Fa84D](https://etherscan.io/address/0x2a098988600d87650Fb061FfAff08B97149Fa84D#code)

Verifier contract for RISC Zero Groth16 proofs (version 3.0.0).


#### DisputeGameFactory

Addresses: [0x43edB88C4B80fDD2AdFF2412A7BebF9dF42cB40e](https://etherscan.io/address/0x43edB88C4B80fDD2AdFF2412A7BebF9dF42cB40e#code), [0x468C2345D1d409d5b0F2f8bE4aE2082150cC1a0c](https://etherscan.io/address/0x468C2345D1d409d5b0F2f8bE4aE2082150cC1a0c#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

The dispute game factory allows the creation of dispute games, used to propose state roots and eventually challenge them. This variant exposes per-type reads only; the legacy array views (gameImpls[], initBonds[]) were removed in the new implementation.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig

Can be upgraded by: Base Governance Multisig with no delay

#### OptimismPortal2

Addresses: [0x49048044D57e1C92A77f79988d21Fa8fAF74E97e](https://etherscan.io/address/0x49048044D57e1C92A77f79988d21Fa8fAF74E97e#code), [0x66d94eE8F529b683ED6013729784e8bb44697A64](https://etherscan.io/address/0x66d94eE8F529b683ED6013729784e8bb44697A64#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

The OptimismPortal contract is the main entry point to deposit funds from L1 to L2. It also allows to prove and finalize withdrawals. It specifies which game type can be used for withdrawals, which currently is the AggregateVerifier.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig

Can be upgraded by: Base Governance Multisig with no delay

#### RiscZeroGroth16Verifier

Addresses: [0x54aCE3ED46529B4d4F3770C8Bad5dDC48717B9bF](https://etherscan.io/address/0x54aCE3ED46529B4d4F3770C8Bad5dDC48717B9bF#code)

Verifier contract for RISC Zero Groth16 proofs (version 2.0.3).


#### SystemConfig

Addresses: [0x73a79Fab69143498Ed3712e519A88a918e1f4072](https://etherscan.io/address/0x73a79Fab69143498Ed3712e519A88a918e1f4072#code), [0x0507Aaa21c678976FCdC7e804836ACd6ebc17a44](https://etherscan.io/address/0x0507Aaa21c678976FCdC7e804836ACd6ebc17a44#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

Contains configuration parameters such as the Sequencer address, gas limit on this chain and the unsafe block signer address.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig
  * **batcherHash**: EOA 1
  * **owner**: Base Multisig 1

Can be upgraded by: Base Governance Multisig with no delay

#### RiscZeroGroth16Verifier

Addresses: [0xafB31f5b70623CDF4b20Ada3f7230916A5A79df9](https://etherscan.io/address/0xafB31f5b70623CDF4b20Ada3f7230916A5A79df9#code)

Verifier contract for RISC Zero Groth16 proofs (version 2.2.0).


#### SuperchainConfig

Addresses: [0xb535ff7F118260a952CE65e7fF41B1743De8EE6c](https://etherscan.io/address/0xb535ff7F118260a952CE65e7fF41B1743De8EE6c#code), [0xc4ceeB264Fa35a022e470aCc3C6A522308f3ec02](https://etherscan.io/address/0xc4ceeB264Fa35a022e470aCc3C6A522308f3ec02#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

Base's own SuperchainConfig, used to manage pause states for the Base chain. The guardian and incident responder roles are immutable and set at construction time. The guardian can pause, unpause, and extend pauses, while the incident responder can only pause. Each pause automatically expires after 3 months.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig
  * **guardian**: Base Governance Multisig
  * **incident_responder**: Base Multisig 1

Can be upgraded by: Base Governance Multisig with no delay

#### RiscZeroGroth16Verifier

Addresses: [0xf70aBAb028Eb6F4100A24B203E113D94E87DE93C](https://etherscan.io/address/0xf70aBAb028Eb6F4100A24B203E113D94E87DE93C#code)

Verifier contract for RISC Zero Groth16 proofs. This older implementation exposes control-root and selector constants but does not expose a VERSION getter.


#### L1StandardBridge

Addresses: [0x3154Cf16ccdb4C6d922629664174b904d80F2C35](https://etherscan.io/address/0x3154Cf16ccdb4C6d922629664174b904d80F2C35#code), [0x61525EaaCDdB97D9184aFc205827E6A4fd0Bf62A](https://etherscan.io/address/0x61525EaaCDdB97D9184aFc205827E6A4fd0Bf62A#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

The main entry point to deposit ERC20 tokens from host chain to this chain.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig

Can be upgraded by: Base Governance Multisig with no delay

#### L1ERC721Bridge

Addresses: [0x608d94945A64503E642E6370Ec598e519a2C1E53](https://etherscan.io/address/0x608d94945A64503E642E6370Ec598e519a2C1E53#code), [0x74f1aC50EB0BE98853805D381C884f5f9abDEcf9](https://etherscan.io/address/0x74f1aC50EB0BE98853805D381C884f5f9abDEcf9#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

Used to bridge ERC-721 tokens from host chain to this chain.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig

Can be upgraded by: Base Governance Multisig with no delay

#### L1CrossDomainMessenger

Addresses: [0x866E82a600A1414e583f7F13623F1aC5d58b0Afa](https://etherscan.io/address/0x866E82a600A1414e583f7F13623F1aC5d58b0Afa#code), [0xb686F13AfF1e427a1f993F29ab0F2E7383729FE0](https://etherscan.io/address/0xb686F13AfF1e427a1f993F29ab0F2E7383729FE0#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

Sends messages from host chain to this chain, and relays messages back onto host chain. In the event that a message sent from host chain to this chain is rejected for exceeding this chain's epoch gas limit, it can be resubmitted via this contract's replay function.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig

Can be upgraded by: Base Governance Multisig with no delay

#### HistoryStorage

Addresses: [0x0000F90827F1C53a10cb7A02335B175320002935](https://etherscan.io/address/0x0000F90827F1C53a10cb7A02335B175320002935#code)

EIP-2935 system contract storing the last 8191 L1 blockhashes. Bytecode is canonical to the EIP, deployed at the same address across networks.


**References**

- [Source Code](https://eips.ethereum.org/EIPS/eip-2935)

#### ProxyAdmin

Addresses: [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code)

* Roles:
  * **owner**: Base Governance Multisig

#### OptimismMintableERC20Factory

Addresses: [0x05cc379EBD9B30BbA19C6fA282AB29218EC61D84](https://etherscan.io/address/0x05cc379EBD9B30BbA19C6fA282AB29218EC61D84#code), [0x8ee6fB13c6c9a7e401531168E196Fbf8b05cEabB](https://etherscan.io/address/0x8ee6fB13c6c9a7e401531168E196Fbf8b05cEabB#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

A helper contract that generates OptimismMintableERC20 contracts on the network it's deployed to. OptimismMintableERC20 is a standard extension of the base ERC20 token contract designed to allow the L1StandardBridge contracts to mint and burn tokens. This makes it possible to use an OptimismMintableERC20 as this chain's representation of a token on the host chain, or vice-versa.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig

Can be upgraded by: Base Governance Multisig with no delay

#### TimelockController

Addresses: [0x0b144E07A0826182B6b59788c34b32Bfa86Fb711](https://etherscan.io/address/0x0b144E07A0826182B6b59788c34b32Bfa86Fb711#code)

A timelock with access control. The current minimum delay is 3d.
* Roles:
  * **canceller**: Safe
  * **defaultAdmin**: TimelockController; ultimately Safe
  * **executor**: Safe
  * **proposer**: Safe

#### TEEProverRegistry

Addresses: [0x1af2A7E537DE2eE795DE5B8BfbB1Ad0DD513A5aA](https://etherscan.io/address/0x1af2A7E537DE2eE795DE5B8BfbB1Ad0DD513A5aA#code), [0xeaB9b34BDD26Ad451B381B0934a30fAa6ED5E316](https://etherscan.io/address/0xeaB9b34BDD26Ad451B381B0934a30fAa6ED5E316#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

Registry of authorized TEE enclave signers and proposer addresses used by the TEEVerifier. Owner can add or remove allowlisted proposers via setProposer (onlyOwner) and set the AggregateVerifier game type lookup. Owner and Manager can register or deregister enclave signers via registerSigner / deregisterSigner. Registration requires a Risc0 ZK proof of a valid AWS Nitro attestation document verified by the NITRO_VERIFIER.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig

Can be upgraded by: Base Governance Multisig with no delay

#### RiscZeroVerifierEmergencyStop

Addresses: [0x1efDd13f831ceeEa14940806705A53D3211CD698](https://etherscan.io/address/0x1efDd13f831ceeEa14940806705A53D3211CD698#code), [0x68dC2cB4e61774873971c499D9b239ec5Ac540E3](https://etherscan.io/address/0x68dC2cB4e61774873971c499D9b239ec5Ac540E3#code), [0x9F9994Eb4Cb5200198FEfb470f8b50301662e696](https://etherscan.io/address/0x9F9994Eb4Cb5200198FEfb470f8b50301662e696#code), [0xDa8f3de6fBBdb261Ac771B813a578A7aBdA6B2b1](https://etherscan.io/address/0xDa8f3de6fBBdb261Ac771B813a578A7aBdA6B2b1#code)

A verifier wrapper for the RiscZeroGroth16Verifier that allows pausing (emergency stop) the verifier by its owner.
* Roles:
  * **owner**: Safe

#### PreimageOracle

Addresses: [0x1fb8cdFc6831fc866Ed9C51aF8817Da5c287aDD3](https://etherscan.io/address/0x1fb8cdFc6831fc866Ed9C51aF8817Da5c287aDD3#code)

The PreimageOracle contract is used to load the required data from L1 for a dispute game.


#### TEEVerifier

Addresses: [0x1FbA0C57b07Af804A9717e51dec9CC27FBC12228](https://etherscan.io/address/0x1FbA0C57b07Af804A9717e51dec9CC27FBC12228#code)

Stateless verifier that validates AggregateVerifier TEE proofs by recovering an ECDSA signature over the journal and checking the recovered signer against TEEProverRegistry. Enforces PCR0 match by comparing the signer's registered image hash to the AggregateVerifier's TEE_IMAGE_HASH. Can be permanently nullified by a successful AggregateVerifier.nullify call.


#### DelayedWETH

Addresses: [0x2453c1216E49704d84eA98a4daCd95738F2fC8Ec](https://etherscan.io/address/0x2453c1216E49704d84eA98a4daCd95738F2fC8Ec#code), [0x33Dadc2d1aA9BB613A7AE6B28425eA00D44c6998](https://etherscan.io/address/0x33Dadc2d1aA9BB613A7AE6B28425eA00D44c6998#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

Contract designed to hold the bonded ETH for each game. It is designed as a wrapper around WETH to allow an owner to function as a backstop if a game would incorrectly distribute funds.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig

Can be upgraded by: Base Governance Multisig with no delay

#### RiscZeroVerifierEmergencyStop

Addresses: [0x44c220f0598345195cE99AD6A57aDfFcb9Ea33e7](https://etherscan.io/address/0x44c220f0598345195cE99AD6A57aDfFcb9Ea33e7#code)

A verifier wrapper for the RiscZeroGroth16Verifier that allows pausing (emergency stop) the verifier by its owner.
* Roles:
  * **owner**: EOA 3

#### RiscZeroSetVerifier

Addresses: [0x5005aBa3DFf7C940fcc1e48DccCAD611a80eEB85](https://etherscan.io/address/0x5005aBa3DFf7C940fcc1e48DccCAD611a80eEB85#code)

Set verifier contract for RISC Zero proofs (version 0.9.0). It allows verifying a whole set of proofs identified with a Merkle root at once, afterwards each individual proof could be efficiently verified just by checking Merkle inclusion against the verified root.


#### PermissionedDisputeGame

Addresses: [0x58bf355C5d4EdFc723eF89d99582ECCfd143266A](https://etherscan.io/address/0x58bf355C5d4EdFc723eF89d99582ECCfd143266A#code)

Same as FaultDisputeGame, but only two permissioned addresses are designated as proposer and challenger.


#### MIPS

Addresses: [0x6463dEE3828677F6270d83d45408044fc5eDB908](https://etherscan.io/address/0x6463dEE3828677F6270d83d45408044fc5eDB908#code)

The MIPS contract is used to execute the final step of the dispute game which objectively determines the winner of the dispute.


#### DelayedWETH

Addresses: [0x64AE5250958CdeB83f6b61f913B5Ac6Ebe8EFd4D](https://etherscan.io/address/0x64AE5250958CdeB83f6b61f913B5Ac6Ebe8EFd4D#code), [0x33Dadc2d1aA9BB613A7AE6B28425eA00D44c6998](https://etherscan.io/address/0x33Dadc2d1aA9BB613A7AE6B28425eA00D44c6998#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

Contract designed to hold the bonded ETH for each game. It is designed as a wrapper around WETH to allow an owner to function as a backstop if a game would incorrectly distribute funds.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig

Can be upgraded by: Base Governance Multisig with no delay

#### FaultDisputeGame

Addresses: [0x6dDBa09bc4cCB0D6Ca9Fc5350580f74165707499](https://etherscan.io/address/0x6dDBa09bc4cCB0D6Ca9Fc5350580f74165707499#code)

Logic of the dispute game. When a state root is proposed, a dispute game contract is deployed. Challengers can use such contracts to challenge the proposed state root.


#### Escrow

Addresses: [0x7F311a4D48377030bD810395f4CCfC03bdbe9Ef3](https://etherscan.io/address/0x7F311a4D48377030bD810395f4CCfC03bdbe9Ef3#code)

Simple escrow that accepts tokens and allows to configure permissioned addresses that can access the tokens.


#### NitroEnclaveVerifier

Addresses: [0x7F3a16E1fe6Fda64c5AC4296E13ECB9F7B44F6fb](https://etherscan.io/address/0x7F3a16E1fe6Fda64c5AC4296E13ECB9F7B44F6fb#code)

ZK-based verifier of AWS Nitro Enclave attestation documents. Used by TEEProverRegistry to validate new enclave signer registrations against the AWS Nitro PKI.


#### RiscZeroVerifierEmergencyStop

Addresses: [0x844D5f01161E3559d36f23d0Aa9E9620949aF782](https://etherscan.io/address/0x844D5f01161E3559d36f23d0Aa9E9620949aF782#code)

A verifier wrapper for the RiscZeroSetVerifier that allows pausing (emergency stop) the verifier by its owner.
* Roles:
  * **owner**: Safe

#### RiscZeroVerifierRouter

Addresses: [0x8EaB2D97Dfce405A1692a21b3ff3A172d593D319](https://etherscan.io/address/0x8EaB2D97Dfce405A1692a21b3ff3A172d593D319#code)

A router proxy that routes to verifiers based on selectors. The mapping can be changed by a permissioned owner (TimelockController).
* Roles:
  * **owner**: TimelockController; ultimately Safe

#### AnchorStateRegistry

Addresses: [0x909f6cf47ed12f010A796527f562bFc26C7F4E72](https://etherscan.io/address/0x909f6cf47ed12f010A796527f562bFc26C7F4E72#code), [0x4483F964F6711Cb55f633820ED174E780369b99D](https://etherscan.io/address/0x4483F964F6711Cb55f633820ED174E780369b99D#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

Contains the latest confirmed state root that can be used as a starting point in a dispute game. This variant stores respectedGameType, retirementTimestamp, and disputeGameFinalityDelaySeconds locally and drops the legacy *FromGame fields, since the AggregateVerifier model does not expose vm()/weth()/absolutePrestate() on its game implementation.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig

Can be upgraded by: Base Governance Multisig with no delay

#### wstETHEscrow

Addresses: [0x9de443AdC5A411E83F1878Ef24C3F52C61571e72](https://etherscan.io/address/0x9de443AdC5A411E83F1878Ef24C3F52C61571e72#code), [0x313819736457910aC1Dd21a712a37f3d7595645A](https://etherscan.io/address/0x313819736457910aC1Dd21a712a37f3d7595645A#code) (Implementation (Upgradable)), [0x3e40D73EB977Dc6a537aF587D48316feE66E9C8c](https://etherscan.io/address/0x3e40D73EB977Dc6a537aF587D48316feE66E9C8c#code) (Admin)

Escrow for custom external tokens that use the canonical bridge for messaging but are governed externally.


#### SkyLink Bridge

Addresses: [0xA5874756416Fa632257eEA380CAbd2E87cED352A](https://etherscan.io/address/0xA5874756416Fa632257eEA380CAbd2E87cED352A#code), [0xaeFd31c2e593Dc971f9Cb42cBbD5d4AD7F1970b6](https://etherscan.io/address/0xaeFd31c2e593Dc971f9Cb42cBbD5d4AD7F1970b6#code) (Implementation (Upgradable)), [0x0000000000000000000000000000000000000000](https://etherscan.io/address/0x0000000000000000000000000000000000000000#code) (Admin)

Custom bridge for USDS and sUSDS managed by Sky governance.


#### ZkVerifier

Addresses: [0xB88D95bDf6972508942d184866890c1834219B75](https://etherscan.io/address/0xB88D95bDf6972508942d184866890c1834219B75#code)

Thin router that forwards SP1 ZK proof verification from the AggregateVerifier game to the SP1 verifier gateway. Can be permanently nullified by a successful AggregateVerifier.nullify call.


#### SP1Verifier

Addresses: [0xc3c6dDDAc8829b233Dc6536Ec024775a57b0AF2A](https://etherscan.io/address/0xc3c6dDDAc8829b233Dc6536Ec024775a57b0AF2A#code)

Verifier contract for SP1 proofs (v6.1.0).


#### DelayedWETH

Addresses: [0xd0D07924AdD740a87e41Ca8A0d4CBBf6b074EF71](https://etherscan.io/address/0xd0D07924AdD740a87e41Ca8A0d4CBBf6b074EF71#code), [0x437c42d7927fe396E54da837d6aC57756cD868e3](https://etherscan.io/address/0x437c42d7927fe396E54da837d6aC57756cD868e3#code) (Implementation (Upgradable)), [0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E](https://etherscan.io/address/0x0475cBCAebd9CE8AfA5025828d5b98DFb67E059E#code) (Admin)

Contract designed to hold the bonded ETH for each game. It is designed as a wrapper around WETH to allow an owner to function as a backstop if a game would incorrectly distribute funds.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig

Can be upgraded by: Base Governance Multisig with no delay

#### SP1VerifierGateway

Addresses: [0xdc32E228636273285Befa5F001dBB5142517C106](https://etherscan.io/address/0xdc32E228636273285Befa5F001dBB5142517C106#code)

This contract is the router for zk proof verification. It stores the mapping between identifiers and the address of onchain verifier contracts, routing each identifier to the corresponding verifier contract.
* Roles:
  * **owner**: Base Governance Multisig

#### AggregateVerifier

Addresses: [0xeE303bA054c5F1E14A8EF87f1C7E285af45A1ba2](https://etherscan.io/address/0xeE303bA054c5F1E14A8EF87f1C7E285af45A1ba2#code)

Game type implementation that combines a TEE attestation arm and a ZK proof arm. A single un-nullified proof of either type can resolve a game (PROOF_THRESHOLD = 1). When both arms commit, the finalization window collapses from SLOW_FINALIZATION_DELAY (5d) to FAST_FINALIZATION_DELAY (1d).


### Base Chain

#### FeeDisburser

Addresses: [0x09C7bAD99688a55a2e83644BFAed09e62bDcCcBA](https://basescan.org/address/0x09C7bAD99688a55a2e83644BFAed09e62bDcCcBA#code), [0x72984FeF9c2123eBB66912CeAB9e47C5E9B738e6](https://basescan.org/address/0x72984FeF9c2123eBB66912CeAB9e47C5E9B738e6#code) (Implementation (Upgradable)), [0xa966054731540a48b28990b63Dcf4f33d8aE57B2](https://basescan.org/address/0xa966054731540a48b28990b63Dcf4f33d8aE57B2#code) (Admin)

Contract used to disburse funds from system FeeVault contracts, shares revenue with Optimism and bridges the rest of funds to L1.
* Roles:
  * **admin**: EOA 2

Can be upgraded by: EOA 2 with no delay

#### L2CrossDomainMessenger

Addresses: [0x4200000000000000000000000000000000000007](https://basescan.org/address/0x4200000000000000000000000000000000000007#code), [0xC0d3c0d3c0D3c0D3C0d3C0D3C0D3c0d3c0d30007](https://basescan.org/address/0xC0d3c0d3c0D3c0D3C0d3C0D3C0D3c0d3c0d30007#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

The L2CrossDomainMessenger (L2xDM) contract sends messages from L2 to L1, and relays messages from L1 onto L2 with a system tx. In the event that a message sent from L2 to L1 is rejected for exceeding the L1 gas limit, it can be resubmitted via this contract’s replay function.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### L2StandardBridge

Addresses: [0x4200000000000000000000000000000000000010](https://basescan.org/address/0x4200000000000000000000000000000000000010#code), [0xC0d3c0d3c0D3c0d3C0D3c0D3C0d3C0D3C0D30010](https://basescan.org/address/0xC0d3c0d3c0D3c0d3C0D3c0D3C0d3C0D3C0D30010#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

The L2StandardBridge contract is the main entry point to deposit or withdraw ERC20 tokens from L2 to L1. This contract can store any token.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### SequencerFeeVault

Addresses: [0x4200000000000000000000000000000000000011](https://basescan.org/address/0x4200000000000000000000000000000000000011#code), [0xd53210eE20948eCFF8B6B8180E29657e0ce8492d](https://basescan.org/address/0xd53210eE20948eCFF8B6B8180E29657e0ce8492d#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

Collects the sequencer fees, which are withdrawable to the FeesCollector on L1.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### OptimismMintableERC20Factory

Addresses: [0x4200000000000000000000000000000000000012](https://basescan.org/address/0x4200000000000000000000000000000000000012#code), [0x6922ac4DbDfEdEa3a1E5535f12c3171f2b964C91](https://basescan.org/address/0x6922ac4DbDfEdEa3a1E5535f12c3171f2b964C91#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

Factory contract to create bridge compliant ERC20 IOU token representations of bridged L1 ERC20 tokens.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### L1BlockNumber

Addresses: [0x4200000000000000000000000000000000000013](https://basescan.org/address/0x4200000000000000000000000000000000000013#code), [0xC0D3C0d3C0D3c0D3C0d3c0D3C0d3c0d3C0d30013](https://basescan.org/address/0xC0D3C0d3C0D3c0D3C0d3c0D3C0d3c0d3C0d30013#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

Simple contract that returns the latest L1 block number.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### L2ERC721Bridge

Addresses: [0x4200000000000000000000000000000000000014](https://basescan.org/address/0x4200000000000000000000000000000000000014#code), [0xC0D3c0d3c0d3c0d3c0D3C0d3C0D3C0D3c0d30014](https://basescan.org/address/0xC0D3c0d3c0d3c0d3c0D3C0d3C0D3C0D3c0d30014#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

The L2ERC721Bridge contract is the main entry point to deposit or withdraw ERC721 tokens from L2 to L1. This contract can store any token.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### L1Block

Addresses: [0x4200000000000000000000000000000000000015](https://basescan.org/address/0x4200000000000000000000000000000000000015#code), [0x3Ba4007f5C922FBb33C454B41ea7a1f11E83df2C](https://basescan.org/address/0x3Ba4007f5C922FBb33C454B41ea7a1f11E83df2C#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

Simple contract that returns information about the latest L1 block, which is derived permissionlessly from the L1 chain.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### L2ToL1MessagePasser

Addresses: [0x4200000000000000000000000000000000000016](https://basescan.org/address/0x4200000000000000000000000000000000000016#code), [0xC0D3C0d3C0d3c0d3C0d3C0D3c0D3c0d3c0D30016](https://basescan.org/address/0xC0D3C0d3C0d3c0d3C0d3C0D3c0D3c0d3c0D30016#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

Contract used internally by the L2CrossDomainMessenger to send messages to L1, including withdrawals. It can also be used directly as a low-level interface.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### OptimismMintableERC721Factory

Addresses: [0x4200000000000000000000000000000000000017](https://basescan.org/address/0x4200000000000000000000000000000000000017#code), [0xc0d3C0d3C0d3C0d3C0d3c0d3C0D3C0d3C0D30017](https://basescan.org/address/0xc0d3C0d3C0d3C0d3C0d3c0d3C0D3C0d3C0D30017#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

Factory contract to create bridge compliant ERC721 IOU token representations of bridged L1 ERC721 tokens.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### ProxyAdmin

Addresses: [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code), [0xC0d3C0D3c0d3C0d3c0d3c0D3C0D3C0d3C0D30018](https://basescan.org/address/0xC0d3C0D3c0d3C0d3c0d3c0D3C0D3C0d3C0D30018#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias
  * **owner**: Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### BaseFeeVault

Addresses: [0x4200000000000000000000000000000000000019](https://basescan.org/address/0x4200000000000000000000000000000000000019#code), [0x4E207bDF8aece56de86821f5370b2b993D08C9E9](https://basescan.org/address/0x4E207bDF8aece56de86821f5370b2b993D08C9E9#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

Collects EIP-1559 base fees, which are withdrawable to the FeesCollector on L1.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### L1FeeVault

Addresses: [0x420000000000000000000000000000000000001A](https://basescan.org/address/0x420000000000000000000000000000000000001A#code), [0x0c9034b92351cF8f067379a1fFA4fa35f5AF9dCC](https://basescan.org/address/0x0c9034b92351cF8f067379a1fFA4fa35f5AF9dCC#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

Collects the L1 portion of the L2 transaction fees, which are withdrawable to the FeesCollector on L1.
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### SchemaRegistry

Addresses: [0x4200000000000000000000000000000000000020](https://basescan.org/address/0x4200000000000000000000000000000000000020#code), [0x75505a97BD334E7BD3C476893285569C4136Fa0F](https://basescan.org/address/0x75505a97BD334E7BD3C476893285569C4136Fa0F#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

Contracts to register schemas for the Ethereum Attestation Service (EAS).
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

#### EAS

Addresses: [0x4200000000000000000000000000000000000021](https://basescan.org/address/0x4200000000000000000000000000000000000021#code), [0xbEb5Fc579115071764c7423A4f12eDde41f106Ed](https://basescan.org/address/0xbEb5Fc579115071764c7423A4f12eDde41f106Ed#code) (Implementation (Upgradable)), [0x4200000000000000000000000000000000000018](https://basescan.org/address/0x4200000000000000000000000000000000000018#code) (Admin)

Contract containing the main logic for the Ethereum Attestation Service (EAS).
* Roles:
  * **admin**: ProxyAdmin; ultimately Base Governance Multisig - L2 Alias

Can be upgraded by: Base Governance Multisig - L2 Alias with no delay

The current deployment carries some associated risks:

- Funds can be stolen if a contract receives a malicious code upgrade. Upgrades must be approved by 2 parties: the Base Coordinator Multisig and the Base Security Council. There is no delay on upgrades.