## Identity

Read on **2026-10-27**. Display name: **Arbitrum One**; category/type: **Optimistic Rollup**; host chain: **Ethereum**; chain ID: **42161**. The HTML summary displayed **$9.77 B USD TVS**, above $500 million; the separately retrieved Markdown representation displayed **$9.83 B**. These are the displayed rounded values, not an independently reconstructed same-block valuation. [L2BEAT summary](https://l2beat.com/layer2s/projects/arbitrum), [L2BEAT Markdown summary](https://l2beat.com/layer2s/projects/arbitrum.md#summary).

Badges: EVM; WasmVM; Ethereum with blobs; Built on Arbitrum Nitro; Governance; L3 Host Chain. [L2BEAT badges](https://l2beat.com/layer2s/projects/arbitrum#badges).

This is the bounded Arbitrum One profile, using only L2BEAT and its repository. Short risk values are reproduced below; longer explanations and checklist requirements are summarized, with direct links to their full wording.

## 1. Stage

**Stage 1**. L2BEAT assesses that exits remain possible despite malicious operators and disappearance of the council. [L2BEAT Stage](https://l2beat.com/layer2s/projects/arbitrum#stage).

The complete displayed checklist is below. “Met” and “Unmet” describe the project's assessment; wording in the requirement column is a summary, not a quotation. [L2BEAT checklist](https://l2beat.com/layer2s/projects/arbitrum.md#stage), [checklist text implementation](https://github.com/l2beat/l2beat/blob/main/packages/config/src/common/stages/getRollupStage.ts).

| Level | Status | Requirement |
| --- | --- | --- |
| Stage 0 | Met | Operational, complete proof mechanism deployed. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-0) |
| Stage 0 | Met | At least five outside parties can file fraud challenges. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-0) |
| Stage 0 | Met | Self-identifies as a rollup. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-0) |
| Stage 0 | Met | Ethereum receives the state-root commitments. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-0) |
| Stage 0 | Met | Ethereum receives the transition inputs. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-0) |
| Stage 0 | Met | Publicly inspectable node software can reconstruct state using Ethereum data; L2BEAT qualifies that it has not validated that software's correctness. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-0) |
| Stage 1 principle | Met | Except for bugs, indefinite censorship of withdrawals/L2→L1 messages, or invalid messages with under seven days for exit, requires compromising at least 75% of council members. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-1) |
| Stage 1 guideline | Met | Exit does not require authorized operators' assistance. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-1) |
| Stage 1 guideline | Met | Upgrades by parties less decentralized than the council leave at least seven days for withdrawal. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-1) |
| Stage 1 guideline | Met | Council setup satisfies L2BEAT's criteria. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-1) |
| Stage 2 | Met | No allowlist restricts fraud-proof submission. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-2) |
| Stage 2 | Unmet | Non-bug-related upgrades leave fewer than thirty days for withdrawal. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-2) |
| Stage 2 | Unmet | Council intervention is not limited to bugs demonstrable onchain. [Source](https://l2beat.com/layer2s/projects/arbitrum.md#stage-2) |

Thus: six Stage 0 conditions and four Stage 1 conditions satisfied; two Stage 2 blockers. The config has four additional ZK-oriented Stage 1 entries set to `null`, not failures: `noRedTrustedSetups`, `programHashesReproducible`, `proverSourcePublished`, `verifierContractsReproducible`. [L2BEAT Stage](https://l2beat.com/layer2s/projects/arbitrum#stage), [project stage inputs](https://github.com/l2beat/l2beat/blob/c88d8d19426a0b26cb60f04afbc064517f8bab3e/packages/config/src/projects/arbitrum/arbitrum.ts).

No project-wide under-review or stage-downgrade banner was visible. The config explicitly sets `display.warning` to `undefined`. The Stage section cautions that its maturity assessment is subjective and does not measure security. [L2BEAT Stage](https://l2beat.com/layer2s/projects/arbitrum#stage), [project display config](https://github.com/l2beat/l2beat/blob/c88d8d19426a0b26cb60f04afbc064517f8bab3e/packages/config/src/projects/arbitrum/arbitrum.ts).

Framework cross-check: the linked explainer still discusses a seven-day minimum, but its linked specification records a **2026-04-30** reduction to **five days** and includes execution/grace periods in optimistic challenge time. It requires a council of at least eight participants, a 75% consensus threshold, diverse independent entities and public identities/pseudonyms. This methodology update is distinct from an Arbitrum stage change; the table above follows the actual project checklist. [Explainer](https://l2beat.com/stages#the-requirements), [specification and changelog](https://forum.l2beat.com/t/the-stages-framework/291).

## 2. Proof system

State Validation value: **“Fraud proofs (INT)”**. [L2BEAT risk analysis](https://l2beat.com/layer2s/projects/arbitrum#risk-analysis).

The proof mechanism is **live**, optimistic, interactive **BoLD**. The milestone dates its permissionless deployment to **2025-02-15**. State proposals and challenges are open to adequately funded participants; the config explicitly sets `permissioned: false`. [L2BEAT State validation](https://l2beat.com/layer2s/projects/arbitrum#state-validation), [L2BEAT milestones](https://l2beat.com/layer2s/projects/arbitrum#milestones), [project proof-system config](https://github.com/l2beat/l2beat/blob/c88d8d19426a0b26cb60f04afbc064517f8bab3e/packages/config/src/projects/arbitrum/arbitrum.ts).

L2BEAT describes **6d 8h** for an uncontested assertion and an additional **2d** execution delay if challenged. Assertions are spaced at least **15m** apart; the proposal bond is **3,600 ETH**, and pooling is supported. Interactive bisection ends with execution of a disputed WASM instruction onchain. An edge's uncontested timer is **6d 8h**, with **12d 17h** maximum edge-confirmation time if both sides delay maximally. Challenge-level bonds are **0 ETH**, **555 ETH**, and **79 ETH**. L2BEAT warns that resource exhaustion can endanger funds. [L2BEAT State validation](https://l2beat.com/layer2s/projects/arbitrum#state-validation), [risk summary](https://l2beat.com/layer2s/projects/arbitrum#risk-summary), [underlying Orbit template](https://github.com/l2beat/l2beat/blob/main/packages/config/src/templates/orbitStack.ts), [discovered parameters](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/discovered.json).

**Permissions cross-check:** no named proposer/challenger allowlist actor appears in the Permissions list. The three EOAs listed there are batch submitters, not the only permitted proof participants. The `RollupProxy` discovery records `validatorWhitelistDisabled: true`. Permissions also lists `OspSoundnessGuard`: anyone demonstrating two rival edges passing one-step verification can trigger a pause through `PauseExecutor`. That special circuit-breaker permission is separate from ordinary validation. [L2BEAT Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions), [discovery data](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/discovered.json).

## 3. Exit window and upgrades

Exit Window values: **“None (emergency upgrade path)”** and **“10d (regular upgrade path)”**. [L2BEAT risk analysis](https://l2beat.com/layer2s/projects/arbitrum#risk-analysis).

Explanation, summarized: ordinary changes start on L2, encounter eight days there and three days on L1; deducting one day for forced inclusion leaves ten days. Emergency changes are immediate, leaving no opportunity to leave first. The calculation intentionally uses those two timelocks, not the entire governance relay duration. [L2BEAT risk analysis](https://l2beat.com/layer2s/projects/arbitrum#risk-analysis), [exit-window calculation](https://github.com/l2beat/l2beat/blob/main/packages/config/src/common/riskView.ts).

The DAO and elected council control upgrades to the critical contracts. Ordinary execution runs through L2Timelock (**8d**), the L2→L1 Outbox (**6d 8h**, plus **2d** if challenged), and L1Timelock (**3d**), then UpgradeExecutor. This gives the **17d 8h** ordinary upgrade delay in Risk summary and Permissions. Emergency council multisigs can skip that path. CoreGovernor uses a **50%** votable-token threshold; treasury proposals have a **40%** threshold and separate **3d** timelock. [L2BEAT Upgrades & Governance](https://l2beat.com/layer2s/projects/arbitrum#upgrades-and-governance), [governance template](https://github.com/l2beat/l2beat/blob/main/packages/config/src/templates/orbitStack/nitroGovernance.md).

The Permissions actors, thresholds, powers and delays are:

| Actor | Threshold | Authority / timing |
| --- | --- | --- |
| Arbitrum Security Council, Ethereum, `0xF06E95eF589D9c38af242a8AAee8375f14023F85` | 9/12 | Immediately upgrades Ethereum contracts listed below, changes rollup parameters and cancels L1Timelock proposals. [Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions), [discovery](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/discovered.json) |
| L2SecurityCouncilEmergency, Arbitrum One, `0x423552c0F05baCCac5Bfa91C6dCF1dc53a0A1641` | 9/12 | Immediately upgrades L2 contracts listed below via L2UpgradeExecutor; its listed interaction changing L2Timelock roles/minimum delay carries **8d**. [Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions), [discovery](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/discovered.json) |
| L2SecurityCouncilPropose, Arbitrum One, `0xADd68bCb0f66878aB9D37a447C7b9067C5dfa941` | 9/12 | Proposes directly into L2Timelock, bypassing the DAO vote but not execution timelocks; upgrades both sets of contracts after **17d 8h**. Its listed change to L2Timelock roles/minimum delay takes **25d 8h**. [Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions), [discovery](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/discovered.json) |
| Emergency Security Council on Arbitrum Nova | 9/12 synchronized council configuration | Governance prose names the third emergency multisig and says it bypasses delays on that chain. Its distinct address is not listed in this page's actors. [Governance](https://l2beat.com/layer2s/projects/arbitrum#upgrades-and-governance), [governance template](https://github.com/l2beat/l2beat/blob/main/packages/config/src/templates/orbitStack/nitroGovernance.md) |
| Arbitrum Multisig 1, Ethereum, `0xd0FDA6925f502a3a94986dfe7C92FE19EBbD679B` | 4/6 | Manages batch posters in SequencerInbox; no waiting period specified for this permission. Not listed as a general upgrader. [Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions), [discovery](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/discovered.json) |
| Arbitrum L2 Multisig 1, `0xe128a8100d1b543dE82d04450B3406d57aBF553b` | 4/6 | Controls TipCollectionToggler, BaseFeeManager and ResourceConstraintManager within bounded fee settings; no waiting period specified. [Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions), [discovery](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/discovered.json) |
| GnosisSafeL2, `0xc610984d9C96a7CE54Bcd335CEee9b0e3874380C` | 3/5 | No action/delay listed in its Permissions entry; discovery identifies it as the election governor's nominee vetter. [Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions), [discovery](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/discovered.json) |

**Ethereum upgrade targets** shared by CoreGovernor / L2SecurityCouncilPropose (delayed) and Arbitrum Security Council (immediate): Outbox, SequencerInbox, UpgradeExecutor, Inbox, RollupProxy, RollupEventInbox, OutboxV0, GatewayRouter, OutboxV1, Bridge, L1ERC20Gateway, EdgeChallengeManager, L1ArbitrumToken, L1ARBGateway, ClassicRollup, L1CustomGateway, L1WethGateway, L1Timelock. Proxy-admin routes include ArbitrumProxyAdmin, GatewaysAdmin, UpgradeExecutorAdmin and ClassicRollupProxyAdmin. [Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions), [discovered permission graph](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/discovered.json).

**L2 upgrade targets** shared by CoreGovernor / L2SecurityCouncilPropose (delayed) and L2SecurityCouncilEmergency (immediate): L2CustomGateway, L2ERC20Gateway, L2Timelock, SecurityCouncilMemberElectionGovernor, L2GatewayRouter, L2WethGateway, SecurityCouncilMemberRemovalGovernor, TreasuryGovernor, L2WETH, SecurityCouncilNomineeElectionGovernor, L2ArbitrumToken, TreasuryTimelock, L2ARBGateway, L2UpgradeExecutor, SecurityCouncilManager, CoreGovernor. These use L2UpgradeExecutor and L2ProxyAdmin / L2GatewaysProxyAdmin. [Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions), [discovered permission graph](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/discovered.json).

**Source inconsistencies retained:** the governance table labels the ordinary exit opportunity approximately **17.4d**, whereas Risk analysis says **10d**. Other considerations separately reports **2d** for L2 upgrades and **11d 8h** for L1, plus **8d** if challenged. Those differ from the **8d + 6d 8h + 3d** route above. The template function's parameter order differs from its project's call order, explaining the inconsistent rendering in Other considerations; this report does not silently replace the displayed values. [Governance](https://l2beat.com/layer2s/projects/arbitrum#upgrades-and-governance), [Other considerations](https://l2beat.com/layer2s/projects/arbitrum#other-considerations), [function signature](https://github.com/l2beat/l2beat/blob/main/packages/config/src/common/upgradeMechanism.ts), [call site](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/arbitrum.ts).

## 4. Data availability

DA value: **“Onchain”**. Data for reconstruction and proofs goes to Ethereum through **blobs or calldata**; the badge specifically indicates blob use. No outside DA service or active Arbitrum One DAC is identified. The Permissions ability to configure DACs is an administrative capability, not evidence of an active DAC. DAC membership/threshold for this rollup: **NOT FOUND / not specified**. [L2BEAT DA](https://l2beat.com/layer2s/projects/arbitrum#data-availability), [badges and DA description](https://l2beat.com/layer2s/projects/arbitrum.md#data-availability), [project blob tracking](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/arbitrum.ts).

## 5. Sequencer and forced inclusion

Sequencer Failure: **“Self sequence”**. Proposer Failure: **“Self propose”**. [L2BEAT risk analysis](https://l2beat.com/layer2s/projects/arbitrum#risk-analysis).

The page identifies a single centralized sequencer controlled by the Arbitrum operator, with redundant instances coordinated through Redis rather than independent consensus. It does not explicitly identify the legal operating entity in these sections: **NOT FOUND**. Permissions lists three authorized batch-poster EOAs: `0x0237e0EA0d86D53aF18dCf4CbE8182037b44ef1A`, `0x0C5911d57B24FCF1DC8B2608eFbAe57C7098E32D`, `0xC1b634853Cb333D3aD8663715b08f41A3Aec47cc`. [Operator and Sequencing](https://l2beat.com/layer2s/projects/arbitrum#sequencing), [Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions), [sequencer description in config](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/arbitrum.ts).

**Forced inclusion is available from L1:** first enqueue through Inbox into Bridge's delayed queue; after the permitted delay, anyone calls SequencerInbox's `forceInclusion` in a second Ethereum transaction. The bound is the smaller of **1d** and the remaining delay buffer; messages delayed beyond **30m** consume that buffer, with a **30m** floor even when exhausted. This fixes ordering, not immediate withdrawal finality. [L2BEAT Operator](https://l2beat.com/layer2s/projects/arbitrum#operator), [Sequencing](https://l2beat.com/layer2s/projects/arbitrum#sequencing), [buffered-inclusion description](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/technologySequencing.md).

The owner can pause Inbox or introduce its allowlist. Censorship resistance therefore depends on Ethereum accepting the enqueue and force transactions and on administrative powers. Autonomous withdrawal also requires the corresponding state assertion and bond; the page's worst-case exit calculation is **15 days 18 hours** (**1d** inclusion plus **14d 18h** state finalization). Ordinary withdrawals await settlement; upgrades can defeat autonomous exit. [L2BEAT Sequencing](https://l2beat.com/layer2s/projects/arbitrum#sequencing), [Withdrawals](https://l2beat.com/layer2s/projects/arbitrum#withdrawals), [exit-delay derivation](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/sequencingExitDelay.md), [calculation and owner restrictions](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/arbitrum.ts).

## Stage history since 2026-04-27

**No stage change found from 2026-04-27 through the 2026-10-27 read.** The current page shows Stage 1 and no pending stage-change banner. I compared the complete `stage` expression in every one of the **15** `arbitrum.ts` revisions returned for this interval against the last pre-window revision. Every criterion and option remained identical; the helper-name change below was the sole expression difference. [Current Stage](https://l2beat.com/layer2s/projects/arbitrum#stage), [file history checked](https://github.com/l2beat/l2beat/commits/main/packages/config/src/projects/arbitrum/arbitrum.ts?since=2026-04-27&until=2026-10-27), [dated API query](https://api.github.com/repos/l2beat/l2beat/commits?path=packages/config/src/projects/arbitrum/arbitrum.ts&since=2026-04-27T00%3A00%3A00Z&until=2026-10-27T23%3A59%3A59Z&per_page=100).

- Baseline: **2026-04-22 10:11:27 UTC**, `65c7f40b08d89af458c2c5008733ad8d98022879`; Stage 0 and 1 applicable entries true; Stage 2 permissionless proofs true, bug-only overrides false, thirty-day exit false. [Commit](https://github.com/l2beat/l2beat/commit/65c7f40b08d89af458c2c5008733ad8d98022879), [baseline file](https://github.com/l2beat/l2beat/blob/65c7f40b08d89af458c2c5008733ad8d98022879/packages/config/src/projects/arbitrum/arbitrum.ts).
- **2026-05-06 11:02:43 UTC**, `995eebbdd8d1f4c660341c19a27cbde34be98b24`: `getStage` renamed to `getRollupStage`, including its import; no criteria changed. This is a code refactor, not a promotion/demotion. [Commit](https://github.com/l2beat/l2beat/commit/995eebbdd8d1f4c660341c19a27cbde34be98b24).
- Latest file revision checked: **2026-10-22 14:18:29 UTC**, `c88d8d19426a0b26cb60f04afbc064517f8bab3e`; same criteria as baseline. No rating-change commit exists among these checked revisions. [Commit](https://github.com/l2beat/l2beat/commit/c88d8d19426a0b26cb60f04afbc064517f8bab3e), [file](https://github.com/l2beat/l2beat/blob/c88d8d19426a0b26cb60f04afbc064517f8bab3e/packages/config/src/projects/arbitrum/arbitrum.ts).

Milestones in the interval concern a governance-related bridge emergency patch (**2026-05-24**), replacement of Timeboost by priority-gas ordering (**2026-09-23**), and suspension of new Stylus activations (**2026-10-02**). None reports a stage transition. The five-day framework change on **2026-04-30** is a methodology change, not an Arbitrum rating-change milestone. [L2BEAT Milestones](https://l2beat.com/layer2s/projects/arbitrum#milestones), [milestone records](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/arbitrum.ts), [framework changelog](https://forum.l2beat.com/t/the-stages-framework/291).

## Not found

- **NOT FOUND:** explicitly named legal sequencer operator or organizational attribution for the three batch-poster addresses. Checked Operator, Sequencing, Permissions and the project config; “Arbitrum operator” is the attribution actually provided. [Sequencing](https://l2beat.com/layer2s/projects/arbitrum#sequencing), [Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions).
- **NOT FOUND:** active Arbitrum One DAC and threshold. Checked DA and Permissions. Historical references to Nova's DAC concern another chain. [DA](https://l2beat.com/layer2s/projects/arbitrum#data-availability), [Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions).
- **NOT FOUND:** distinct Nova emergency-council address on this profile; its synchronized threshold and bypass power are described, but Nova's separate profile was outside this item. [Governance](https://l2beat.com/layer2s/projects/arbitrum#upgrades-and-governance).
- **NOT FOUND:** mandatory delays for Arbitrum Multisig 1, Arbitrum L2 Multisig 1 or GnosisSafeL2's limited actions. Their Permissions entries do not specify such delays; none is inferred. [Permissions](https://l2beat.com/layer2s/projects/arbitrum#permissions).
- **NOT FOUND:** a proposer/challenger whitelist Permissions entry restricting current BoLD participation. State validation, Stage and the whitelist-disabled discovery flag instead establish permissionless participation subject to funding. [State validation](https://l2beat.com/layer2s/projects/arbitrum#state-validation), [discovery](https://github.com/l2beat/l2beat/blob/main/packages/config/src/projects/arbitrum/discovered.json).
- **NOT FOUND:** an authoritative reconciliation of the conflicting exit/upgrade numbers. The report preserves the risk-panel value separately from the governance table and Other considerations. [Risk analysis](https://l2beat.com/layer2s/projects/arbitrum#risk-analysis), [Governance](https://l2beat.com/layer2s/projects/arbitrum#upgrades-and-governance), [Other considerations](https://l2beat.com/layer2s/projects/arbitrum#other-considerations).
- **NOT FOUND:** newest Nitro node/prover software release and release date, if needed for the parent goal. State derivation names Nitro and Program Hashes names an ArbOS v61 binary commitment, but these do not establish the newest software release. Checked those sections and Milestones; did not visit Offchain Labs repositories because this item permits only L2BEAT and its own repository. [State derivation](https://l2beat.com/layer2s/projects/arbitrum#state-derivation), [State validation](https://l2beat.com/layer2s/projects/arbitrum#state-validation), [Milestones](https://l2beat.com/layer2s/projects/arbitrum#milestones).

Long checklist text and explanatory prose are linked and summarized rather than reproduced in full. Cross-rollup ranking is outside this single-profile item.