What Is Arcus? The Stock-Token and Perps DEX on Robinhood Chain (2026)

Arcus

Arcus is a self-custodial decentralized exchange on Robinhood Chain where users in eligible countries trade two things: tokenized US stocks and ETFs (called Stock Tokens) on spot with no Arcus trading fee, and perpetual futures on crypto, equities, index ETFs and commodity ETFs with up to 50x leverage. It went live on July 1, 2026. The team that built dYdX builds it, Robinhood Crypto has invested in it, and both products are still labeled beta. If you want to look around first, the app is at app.arcus.xyz.

This is the overview page. I go through the two trading engines, the companies behind Arcus, today's markets, access, costs and the risks I would want to know about before depositing. Each section links to a deeper guide.

Arcus at a glance

Two engines under one account

Spot and perps on Arcus run on completely different machinery. They share a wallet and a dollar (USDG), but your money sits in separate Spot and Perps balances and you move it between them with a toggle.

Spot: a router and RFQ quotes, no order book

When you buy a Stock Token such as NVDA, there is no order book in the middle. You sign a trade intent with a hidden minimum price, and the Arcus Spot Router collects firm quotes from Arcus's RFQ market makers, Uniswap v2, v3 and v4 pools, and other venues. The router's own health endpoint lists Arcus, Rialto and Bebop as current sources. The single best quote settles atomically on Robinhood Chain. Most token-to-token swaps are gasless, but keep a little ETH on Robinhood Chain for the actions that are not.

Arcus charges no trading fee on Stock Tokens. Your cost is the spread built into the quote, which widens when US markets are closed. The tokens themselves are issued by Bitstamp (Bitstamp Global Ltd., BVI), according to Arcus's docs. A Stock Token gives you a contractual right to redeem with the issuer for the cash value of the share, not the share itself, and no voting rights. Arcus is the venue, not the issuer.

Arcus explains the split in its post on why it uses RFQ for Stock Tokens and an order book for perps. The 24/7 detail, including which names quote on weekends, is in trading stocks 24/7 on Arcus.

Perps: an off-chain order book anchored to a chain

Perpetuals use a hybrid design that Arcus's architecture page describes in layers:

1. Core exchange. API servers, a sequencer and a central limit order book (CLOB) matching engine run off-chain. Arcus claims 100,000+ orders per second and about 20 ms trade confirmations.
2. Arcus appchain. A permissioned set of validators re-verifies signatures, margin and fills, then posts state roots.
3. EVM rootchain. Contracts on Robinhood Chain (a Checkpoint Manager and a Bridge Vault) hold your USDG collateral and handle final settlement, including an escape hatch.
4. Data availability. Block data is published to decentralized storage.

Arcus's own Help Center makes the comparison plainly: "It's the same hybrid model dYdX v3 ran on StarkEx." That matters because many people assume Arcus is a fork of dYdX v4, the Cosmos appchain. It is not. It does not run on dYdX Chain, uses its own /v1 API, and does not use the DYDX token. Oracle prices come mainly from Pyth Pro. The Arcus and dYdX guide covers the family tree in full.

Who builds and runs Arcus

Arcus's ownership gets misreported a lot. KuCoin News, for one, called it a protocol "from Robinhood," which it is not. The official sources say this:

• dYdX Labs builds it. Eddie Zhang's launch post calls Arcus "a next-generation decentralized exchange built by dYdX Labs in partnership with Robinhood Crypto." dYdX's own site identifies that company as "dYdX Trading Inc. dba dYdX Labs." Zhang is CEO of dYdX Labs and founder of Arcus. dYdX Labs acquired his startup, Pocket Protector, around June 2025.
• Antonio Juliano joins the board. The dYdX founder wrote in "A New Arc" that Arcus "was incubated at dYdX Labs and I'll be joining the board where I'll drive strategy and long-term vision."
• Robinhood Crypto is an investor, not the owner. The Help Center answers the question directly: "Is Arcus owned by Robinhood? No. Arcus is an independent DEX." Robinhood Crypto made an undisclosed investment.
• dYdX Chain is separate. Arcus's FAQ says "dYdX Chain continues to operate," and the dYdX Foundation called Arcus "a distinct, independent product built on separate infrastructure."

The legal entities named in Arcus's terms:

The Interface Terms state that the interface operator is not registered with or regulated by the SEC, the CFTC or any other financial regulator, and the site footer says "Arcus is not a regulated financial services provider." Read the terms yourself before depositing. Nothing here is legal advice.

What you can trade

Perpetual futures

The live markets endpoint listed 67 perpetual markets on October 2, 2026, with 60 online: 25 crypto, 34 single equities, 4 commodity ETFs and 4 index ETFs (/v1/markets, checked 04:36 UTC). Across the online markets, open interest was about $44.7 million and 24-hour volume about $503 million, with BTC alone close to $308 million of that.

Leverage depends on the market. The headline "up to 50x" applies to SPY only. BTC goes to 40x; ETH, QQQ, GLD and SLV to 25x; NVDA, AAPL and SOL to 20x; most single stocks to 10x; and smaller names like SPCX (SpaceX) or DYDX to 5x. When the underlying US market is closed, RWA perps switch to an off-hours regime with higher initial margin, price bands and funding locked to SOFR plus 0.5% (docs). Cross margin is the default and isolated margin has been live since September 2026. TWAP, trailing stops, OCO orders and hedge mode are not supported.

For a feel of the BTC book and live data, see the BTC market page, SPY and NVDA.

Spot Stock Tokens

Arcus says it offers "over 190" Stock Tokens. Its spot router listed 242 tokens on Robinhood Chain on October 2, of which 179 were single stocks, 14 index or bond ETFs and 3 commodity ETFs, alongside pTokens, community tokens, ETH and USDG (router token list). Orders run from $10 to $1,000,000. The most liquid names quote 24/7; others quote 24/5.

Arcus also issues pTokens, ERC-20 tokens that wrap a leveraged perp position (pBTC3x, sGLD5x and similar). They are leverage products, not a governance token. The pTokens guide explains how they work and what they cost.

Collateral: USDG only

Perps are quoted, margined, settled and funded in USDG, the Global Dollar stablecoin issued by Paxos (Help Center). You do not need to buy USDG first. Deposits run through Fun, which converts crypto from Ethereum, Arbitrum, Base, Solana, Bitcoin and other chains, or cash via card, Apple Pay and Google Pay. Arcus charges nothing of its own on deposits and withdrawals; third-party costs show before you confirm.

Using Stock Tokens, BTC or ETH as perp margin is on the roadmap but not live. Withdrawing perps funds is a two-step move: Perps to Spot, then Spot out to another chain. The deposit and withdrawal guide walks through both directions, and sign-in works with an email-based Privy wallet or an external wallet like MetaMask.

Access: spot is open, perps are gated

Spot needs no code and no waitlist if you are in an eligible region. Connect a wallet, fund it and trade.

Perps are different. From July 1 to September 30, 2026, Arcus released perps access to waitlisted users in cohorts. On October 1 it switched to invite codes: every $1 million of qualifying perps volume (your own plus your direct referrals') earns one single-use code, and anyone holding a code can start trading perps right away. Codes never expire and cannot be sold or transferred. Existing traders kept their access.

Fees in one table

Tiers run on rolling 30-day perps volume, from Base up to Max ($3 billion), where makers earn a small rebate. During beta the base taker rate is half of Hyperliquid's base taker; after beta the two match. The Arcus fees explained guide has every tier, funding mechanics and worked examples, and the fee calculator does the math for your size.

Arcus also gives referred users 5% off trading fees ("Receive 5% off on all trading fees," per the app; the API changelog for July 22, 2026 lists a "5% referral fee discount for referred users"). The code has to go on early, before your rolling 30-day volume reaches about $1 million, and it cannot be changed later. Our code is ARCUSGUIDE, and ArcusGuide earns a share of the fees from traders who use it. The referral code guide covers the fine print.

Points, and the token question

Arcus launched Arcus Points on October 1, 2026. Season 0 covered the July to September beta and has been distributed; Season 1 pays out weekly on Wednesdays. Points weigh how you trade as well as how much, plus market making, retained deposits and referrals, with boosts for trading Stock Tokens and RWAs and for trading outside US market hours.

There is no Arcus token. dYdX's founder wrote that "an allocation of any future Arcus token will be reserved for the dYdX community," and that sentence is the only official hint of a token at all. Annex C of the Protocol Terms says points do not convey any right to a token generation event or airdrop, and Arcus can change or forfeit them, including retroactively. The points and airdrop guide separates what is confirmed from what is speculation.

Security: audits and trust assumptions

Two firms reviewed Arcus's rootchain contracts, the code that holds perps collateral on Robinhood Chain.

• Trail of Bits reviewed the v5 rootchain contracts from June 10 to 16, 2026. It found three issues: one medium-severity bug that let any caller skip the anti-spam gas burn on the permissionless request queue, and two informational findings. Its fix review on June 25 marked all three resolved, and the report says the review "did not uncover a way to move or strand user funds" (report PDF).
• OpenZeppelin audited the same repository from June 1 to 12, 2026 and reported 13 issues: zero critical, high or medium, five low (four resolved) and eight notes (all resolved) (audit).

Clean audits do not remove the trust built into the design, and OpenZeppelin spells it out: the validator quorum is "the system's effective superadmin," able to "move funds, reconfigure custody, and upgrade any contract in a single action, with no delay and no veto." Add to that what Arcus's own docs say:

• The matching engine "operates in a centralized manner," run by Arcus.
• The appchain validator set is permissioned.
• If Arcus or the validators go offline, the escape hatch lets users exit against the last committed state root, and trades after that root "would be 'busted.'"
• The escape hatch protects against validators disappearing. OpenZeppelin notes it does not protect against a live validator set that misbehaves.

The audits covered the rootchain only. I found no published audit of the spot RFQ settlement, the wrapped-token escrow or the pToken contracts. No Arcus hack or exploit has been reported. Robinhood Chain itself had a short disruption on September 4, 2026 (about 14 minutes of paused block production, around 40 minutes of degraded app traffic, no losses reported), covered in what is Robinhood Chain. There is no deposit insurance.

Where Arcus is not available

Arcus's Interface Terms and Protocol Terms bar "Restricted Persons," defined as anyone who resides in, is located in or is incorporated in the United States, Canada or the United Kingdom, plus sanctioned countries and regions such as Iran, Cuba, North Korea, Crimea, Donetsk and Luhansk. The Help Center adds Switzerland for spot. In practice the app blocks both spot and perps for US visitors. The terms also prohibit using any tool to get around these restrictions, and wallets that break the rules can be blocked.

If you are in one of these places, Arcus is not for you, and Arcus not available in your country explains what the restriction covers. This is a summary of the terms, not legal advice.

How big is Arcus, really?

Arcus's own numbers, as of October 1, 2026: "$5B+ in total trading volume," "15,000+ unique traders," "$500M+ in peak daily trading volume" and a perps waitlist of "more than 100,000 traders" (Arcus blog). Those are self-reported.

Independent data puts that in context. On DefiLlama on October 2, Arcus ranked #19 of 209 derivatives protocols by 30-day volume ($4.11 billion, about 0.66% of the market) and #7 by 24-hour volume, after volume roughly quadrupled from September 27 around the end of points Season 0. On Robinhood Chain it is the second-largest perps venue: Lighter's separate Robinhood Chain exchange did about three times Arcus's 30-day volume. Arcus's BTC book is tight at the top (about $3 million each side within 0.1% in our snapshot) but thin beyond that. The Arcus vs Hyperliquid and Arcus vs Lighter comparisons go through depth, fees and volume side by side.

Who Arcus suits, and who it does not

Arcus fits you if:

• You live in an eligible country and want US stock exposure 24/7 from your own wallet, with no Arcus fee on spot.
• You trade equity, index or crypto perps and want a taker fee half of Hyperliquid's base rate while the beta lasts.
• You want self-custodied Stock Tokens and equity perps in one account. Among the order-book perps venues I compared, Arcus is the only one that pairs the two.
• You build bots: Arcus has a public REST and WebSocket API, sub-accounts and an MCP server.

Look elsewhere if:

• You are in the US, Canada, the UK or another restricted region.
• You need deep books for large market orders. Hyperliquid's BTC book is roughly ten times deeper within 0.1%.
• You want zero perp fees. Lighter Standard accounts and some other venues charge nothing at the base level.
• You need TWAP, trailing stops, OCO or hedge mode, which Arcus does not support yet.
• You cannot accept trusting a centrally operated matching engine and a permissioned validator set.
• You are hoping for a guaranteed airdrop. Nothing official promises one.

How to start

1. Open app.arcus.xyz and sign in with email or connect a wallet.
2. Fund your account with crypto or cash through the deposit flow.
3. Trade Stock Tokens on spot right away, or redeem an invite code to unlock perps.

The how to trade on Arcus guide walks through every screen, from first deposit to first perp order.