Coinbase Tokenized Stock, explained: a trust certificate on Base, closed to U.S. persons

What the holder owns

The issuer is Coinbase Onchain SPV Ltd, incorporated in the Abu Dhabi Global Market on 17 June 2026. Its sole shareholder is Onchain Marketplace Holdings Limited, “an indirect wholly owned subsidiary of Coinbase Global, Inc.” The ADGM’s regulator approves a prospectus for each stock; NVIDIA’s was approved on 4 August 2026.¹

This is the custodial model, not a note. “Each Security represents a pro rata beneficial interest in the Deposited Property (as a whole) attributable to the Securities held by the Issuer on trust for Holders.” Alpaca Securities holds and buys the shares. Even so, “The Securities do not constitute direct investments in the Underlying.”¹ Base’s listing page calls them “individual US company shares brought onchain.”² The prospectus is the document that binds the issuer, and it says otherwise.

Who counts as a holder depends on a register, not the chain. “The Legal Register constitutes the definitive and exclusive record of legal title to the Securities,” and Onchain Marketplace Ltd, a sister company authorised as a central securities depository, keeps it. A buyer who has passed that company’s checks, proved control of the wallet, and named a bank account becomes a Vested Holder on the register. A buyer on a decentralized exchange who has not is an Unvested Holder: “The Issuer is recorded as the Registered Owner of Unvested Securities, which it holds as bare trustee.”¹

The rights are thinner than a share’s. “Holders of the Securities do not have direct voting rights”; the issuer may “endeavour to vote” on holders’ instructions, but is not obliged to where it judges that impractical. “Holders will not receive cash dividends.” U.S. withholding of 30% comes off each dividend, the issuer takes “a fee of 5.0% of the gross aggregate value,” and the rest is reinvested.¹

Can a US client own it?

No. The prospectus says, in capitals, that the certificates “MAY NOT BE ACQUIRED, HELD, OFFERED, SOLD, RESOLD, TRANSFERRED, DELIVERED, OR OTHERWISE MADE AVAILABLE, DIRECTLY OR INDIRECTLY, IN THE U.S. OR TO, OR FOR THE ACCOUNT OR BENEFIT OF, ANY ‘U.S. PERSON.’”¹ Base’s page says “Available only in eligible jurisdictions outside the US,” and publishes no country list.² The word “held” matters: the bar covers owning the certificate, not only buying it from Coinbase.

Outside the United States there is no minimum. Only Authorised Participants create certificates, at a fee of 0.01%; everyone else buys on chain, in fractions.¹

Who holds the freeze key

The prospectus says the contract “includes blacklist, freeze, and pause functions operable by the Tokenisation Entity in its capacity as CSD, which remain available throughout the Security lifecycle and operate without requiring counterparty cooperation.” It also warns that a change in the vesting conditions, even after a holder has vested, “may result in the freezing or confiscation of the Securities.”¹

On chain the tokens are B20 tokens: code built into Base itself rather than a contract the issuer deployed, so Base, not the issuer, controls the code. The issuer controls roles. On 23 September 2026 the admin role on NVDAc was held by 0x38467be0…, an address with no contract code: a single private key. The admin can grant every other role, including the ones that block an address and burn its balance. No address held the pause or burn roles that day; the admin can grant them at will.³⁴

Base scheduled a wider power for 30 September 2026. Its Cobalt upgrade adds seizeWithMemo, which “reassigns a holder’s balance to a destination in one admin call” for whoever holds a new SEIZE_ROLE.⁵ Base’s upgrades page listed mainnet as “Targeting September 30, 2026,” and a pending change to Base’s documentation marks Cobalt live on mainnet from 18:00 UTC that day.⁶⁷ Ketju re-reads the roles once the upgrade shows on chain.

How a holder gets out

A Vested Holder redeems through Onchain Marketplace Ltd and chooses shares delivered to a brokerage account, U.S. dollars, or USDC, for a fee of 0.05%. No time is promised. An Unvested Holder cannot redeem at all: “Unvested Holders shall not be entitled to redeem Securities or withdraw Underlying.”¹ For them the exit is a sale on a decentralized exchange on Base, into whatever liquidity the Authorised Participants supply.

The certificates are now loan collateral too. On 25 September 2026 Aave opened a market on Base that lends USDC against seven of them. Over weekends and U.S. holidays the price feeds “hold the last published price, so collateral values do not change until the underlying market reopens,” and a reserve is “paused until the new token multiplier is applied” after a split or dividend.⁸ The tokenized securities guide walks a lender through that loan.

What has gone wrong or changed

• 17 June 2026. Coinbase Onchain SPV Ltd is incorporated in the ADGM.¹
• 4 August 2026. The ADGM’s regulator approves the first prospectuses, NVIDIA’s among them.¹
• 3 September 2026. Six more prospectuses follow, from Amazon to SpaceX; Base lists ten tokens.²⁹
• 23 September 2026. Ketju’s memo rejected the program for U.S. clients. The research file gives the reasons.
• 25 September 2026. Aave’s market on Base begins lending USDC against seven Coinbase certificates.⁸
• 30 September 2026. Base’s Cobalt upgrade, scheduled for that day, adds a seize power to B20 tokens.⁵

What an advisor should record

• That the client holds a Coinbase Onchain SPV certificate over shares held on trust, not a share.
• Whether the client is a Vested Holder on the Legal Register, with the date, or an Unvested Holder who cannot redeem.
• Where and when the client acquired it, and the client’s U.S.-person status on that date.
• The admin key on the token, and any grant of the pause, burn, or seize roles; a grant reopens the file.
• The dividend fee and withholding taken, from the multiplier on the token.
• Any use of the certificate as loan collateral, and on which market.

The NVDA ticker page sets NVDAc beside every other tokenized version of the same stock, and the Atlas chart for Base records who controls the chain.