S&P Global said it has agreed to acquire OpenZeppelin, the blockchain security firm behind the open-source smart-contract libraries used by most of the largest stablecoins and tokenized funds. The deal marks another step into on-chain markets for one of the oldest names in credit ratings, pairing a legacy ratings institution with one of the most widely used codebases in decentralized finance.

OpenZeppelin builds and audits software for blockchain-based finance. Its open-source Contracts library supplies the code that developers use to build DeFi protocols and tokenized assets. According to S&P Global, the library supports more than $37 trillion in value transferred, while OpenZeppelin has carried out more than 900 security engagements for protocols and institutions across digital-asset markets. The firm said those reviews have uncovered more than 10,000 vulnerabilities before the code reached production. Much of that value, in other words, moves across code that a single firm wrote or reviewed — the security layer S&P Global is acquiring.

The acquisition expands S&P Global's existing business into on-chain markets. Yann Le Pallec, President of S&P Global Ratings, said the company's digital assets strategy is focused on bringing trusted data, benchmarks, and transparent risk assessments to markets as they move on-chain. He added that OpenZeppelin's work would complement the company's existing capabilities in smart-contract and technology risk assessment. The fit reflects how risk works on-chain: where traditional ratings assess balance sheets and cash flows, smart-contract risk assessment examines the code that holds and moves funds — the layer where software flaws can put user assets directly at risk.

OpenZeppelin confirmed the agreement in a post on X:

Today we are announcing that S&P Global has entered an agreement to acquire OpenZeppelin. Onchain finance is growing from an emerging market into core financial infrastructure, and the standards and rails our team and community built are becoming the rails of global finance.… pic.twitter.com/iADnpWzQ8F

— OpenZeppelin (@OpenZeppelin) September 17, 2026

OpenZeppelin to operate as a standalone unit

OpenZeppelin will retain its name and operate as a separate business unit within S&P Global, according to the S&P Global press release. Co-founder Demian Brener will remain chief executive and will report directly to Le Pallec.

The company also moved to reassure developers, saying its Contracts libraries will remain open source, free, and publicly maintained on GitHub. OpenZeppelin added that existing audits, engineering work, and ecosystem programs will continue under the same teams as before. For developers, the assurance addresses the question that follows any widely used open-source project into an acquisition: whether the code they build on stays publicly maintained rather than absorbed into a proprietary product.

Brener said OpenZeppelin was founded 10 years ago with a vision of building a secure global financial system powered by blockchain-based smart contracts. Joining S&P Global, he added, could help the standard built by the company's team and community become the foundation for the next generation of global finance.

Terms undisclosed, shares little changed

S&P Global did not disclose the financial terms of the transaction, and the company said the acquisition is not expected to have a material effect on its financial results. The deal remains subject to conditions that must be met before it is finalized.

Investors appeared to view the acquisition as a relatively small addition, with S&P Global shares up 1.04% at $411 in premarket trading on the NYSE. Jefferies LLC and Clifford Chance are acting as advisers to S&P Global, while FT Partners and Cooley are advising OpenZeppelin.

The acquisition follows a string of recent deals by S&P Global, including an agreement to buy data-center research firm DatacenterHawk and a deal for a majority stake in Nigeria's Agusto & Company. Attention will now shift to whether the transaction secures the necessary approvals from regulators and how S&P Global plans to turn OpenZeppelin's security expertise into new risk products for on-chain markets.