What is Arcus? The stock token DEX on Robinhood Chain

Arcus is a self-custodial decentralised exchange for tokenized US stocks, indices, commodities and crypto, running spot and perpetual futures 24 hours a day on Robinhood Chain. It was built by the team behind dYdX, with Robinhood Crypto as a strategic investor. It is not available in the United States, the United Kingdom or Canada.

The fuller answer to what is Arcus sits in two separate markets under one interface, and in a blockchain most people have never used. Both are worth understanding before you fund anything.

Who cannot use Arcus

Start here, because it decides whether the rest of this page matters to you. Per the Arcus help centre, Arcus is not available in the United States, the United Kingdom or Canada, and the protocol terms additionally exclude sanctioned persons and comprehensively sanctioned regions, naming Iran, Cuba, North Korea, Crimea, Donetsk and Luhansk. The minimum age is 18.

That is an unusual shape for a product built around US equities. The three blocked countries are also where most English-language searches for tokenized stocks come from, so a large share of the people reading about Arcus cannot open an account at all. The eligibility and countries page goes through how to check your own case and what the realistic alternatives look like.

Two markets, two different mechanisms

Most exchanges run one matching engine for everything. Arcus runs two, deliberately, and Arcus published its reasoning in a design post on its own blog.

Spot Stock Tokens trade by request for quote. You ask for a price, market makers quote, you accept or you do not. There is no visible order book to rest a bid in.

Arcus charges no fee of its own on spot Stock Tokens, which sounds like free trading until you notice where the cost moved: into the quote and the spread. Arcus itself notes that slippage widens outside US market hours, which is exactly when a 24/7 venue is most interesting. More on that in Arcus Stock Tokens.

Perpetual futures trade on a central limit order book, the familiar model from crypto perps venues. Leverage runs up to 50x depending on the market, collateral and quoting are in USDG, the Paxos Labs stablecoin, and Stock Tokens can also be posted as perps collateral. Cross and isolated margin are both supported, with isolated positions shipping on 9 September 2026. The perps page covers the markets and margin modes in detail.

The important asymmetry: spot is open to anyone eligible, perps are not. Perps access runs on invite codes, minted at a rate of one per $1 million of qualifying perps volume, your own plus your direct referrals’, and codes cannot be transferred, sold or reassigned. Arcus puts it bluntly: the only way to get a code is from someone already trading on Arcus.

Before codes went live on 1 October 2026 there was a waitlist, opened 6 July 2026, where spot volume counted toward queue position. If you see somebody selling a code, see how invite codes actually work first.

What Robinhood Chain is, and why Arcus runs there

Robinhood Chain is a permissionless Arbitrum-based Ethereum layer 2 operated by Robinhood. Per the Arbitrum DAO forum factsheet, mainnet went live on 1 July 2026 with Uniswap and Chainlink deployed from day one, and Arcus launched on it the same day alongside other launch partners including Lighter and Pump.fun.

One consequence matters more than it should: you pay gas in ETH on Robinhood Chain. Not USDG, not a gas abstraction. You need a small amount of ETH bridged onto that chain before anything moves, and this is the most common place a first session stalls.

The deposit guide and how to use Arcus both walk through it. Background on the chain itself is in Robinhood Chain explained.

Onboarding uses Privy embedded self-custodial wallets with email or social login and no seed phrase step, so the sign-up feels like an app rather than a wallet. Custody is still self-custodial: Arcus says it never holds your funds or keys, spot settles wallet to wallet on-chain, and perps collateral sits in Robinhood Chain contracts that move only under user-authorised conditions.

Who built Arcus

The operating entity is Arcus Labs Ltd, a Cayman Islands exempted company, with terms governed by Cayman law and last updated 30 June 2026.

Eddie Zhang is CEO and founder. He co-founded Pocket Protector in 2024, dYdX Labs acquired it in July 2025, and he then became president of dYdX. His earlier background, per dYdX’s own announcement and coverage in The Block and CoinDesk, runs through Eventbrite, Facebook, Blackstone, Disney and Citigroup Hong Kong.

Antonio Juliano, who founded dYdX, sits on the Arcus board. Robinhood Crypto is a strategic investor; the amount, valuation and round structure are undisclosed everywhere, including Dealroom, so treat any specific figure you see as invented.

What Arcus is not

Three claims circulate that the primary sources contradict.

It is not a dYdX rebrand. Several outlets wrote exactly that. dYdX’s own post says Arcus was incubated at dYdX Labs and is built jointly by dYdX Labs and Robinhood Crypto, while dYdX v4 “will continue to be supported and your funds and positions will remain fully accessible on dYdX Chain”. Arcus calls itself the next chapter for the team that built dYdX. Two products, one lineage.

The side by side comparison spells out the differences.

It is not owned by Robinhood. Arcus states that it is an independent DEX. Robinhood operates the chain and invested in the company, which is close, but not ownership.

There is no Arcus token. The help centre is verbatim about it: “No, Arcus does not currently have a token.” dYdX has said an allocation of any future Arcus token would be reserved for the dYdX community, which describes a contemplated token, not an announced one. Arcus Points started Season 1 on 1 October 2026 and Arcus describes them as a participation metric only, with allocation at its sole discretion.

A Solana SPL token using the ARCUS ticker is indexed by price aggregators; since Arcus says it has no token, anything on sale under that ticker is not an official Arcus asset. The token page and the points page have the rest.

How big is it, honestly

Two sources disagree by roughly an order of magnitude, and it is worth seeing both.

Arcus, reported by The Block on 1 October 2026: more than $5 billion cumulative volume, more than 15,000 unique traders, more than $28 million TVL and 190+ stock tokens. The DefiLlama API on the same day: $1.02 million 24 hour volume, $27.1 million over 7 days, $111.2 million over 30 days and $343.8 million all time. CoinGecko the same week counted $2.31 million of 24 hour spot volume across 162 pairs.

The likeliest explanation is spot-only tracking against perps notional, but DefiLlama’s methodology could not be confirmed, so the gap stays unexplained here rather than resolved in either direction. Separately, The Block’s July figures of 3.1 billion volume and 65,000 users describe Robinhood Chain as a whole, not Arcus.

Is it worth your time

If you are outside the blocked countries, want US equity exposure outside US market hours and are comfortable holding a self-custodial wallet, the spot side is the part you can actually use today. If you came for 50x stock perps, the invite gate means you probably cannot start now. The full review argues both sides, and fees covers what the 0% spot headline really costs.

One thing to keep in view throughout. This is high-risk trading. Leveraged positions can be liquidated and most leveraged traders lose money.

Stock Tokens are not shares: no voting rights, no dividend claim as such, not necessarily redeemable, and a price that can drift from the real stock. Nothing here is financial advice.