Ondo Finance says it has launched a U.S. implementation of third-party tokenized securities that keeps the underlying shares inside existing custody and brokerage infrastructure.

The first assets named in the launch are BlackRock's iShares Core S&P 500 ETF, ticker IVV, and Micron shares. Ondo says its registered transfer agent, Oasis Pro TA, mints tokenized security entitlements backed one-for-one by the underlying securities. The tokens are issued on Ethereum while regulated custodians continue to hold the traditional shares.

The structure is designed around a January SEC staff statement that described third-party tokenized securities models, including a custodial version where a crypto asset represents an entitlement to an underlying security held in custody. Ondo is presenting the launch as a production deployment of that model rather than a synthetic exposure product.

Broadridge is also part of the rollout. Ondo says token holders will receive issuer communications, regulatory disclosures, and proxy voting access through Broadridge's ProxyVote.com system, with transfer restrictions enforced by the participating broker-dealer, transfer agent, and custodian.

The launch is notable because tokenized equities in the U.S. have often run into questions about custody, investor rights, and market plumbing. Ondo's version does not remove those questions, but it narrows the experiment: the token is a record and access layer around securities that remain in the regulated custody chain.

For now, the meaningful test is operational rather than promotional. If the model works beyond two initial assets, it could give tokenized securities providers a more concrete path for matching onchain access with traditional shareholder protections.