Book-entry equity · Onchain settlement
The Open Cap Table Protocol extends the Open Cap Table Format onchain: issuer equity as programmable book-entry on distributed infrastructure. Fast settlement, tamper-evident audit trails, and rule-based controls aligned with securities obligations, without inventing a new cap table data model.
The protocol
Ownership and transfers are recorded with enforceable restrictions, clear provenance and automation that cuts operational friction for issuers, transfer agents, broker-dealers and investors, whether the stock is privately held or publicly traded. Controls you can audit, settlement you can reconcile, policy you can enforce in code.
Structured data aligned with the Open Cap Table Format, so transfers, restrictions and reconciliation stay consistent across implementations and compatible with industry cap table workflows.
Near-instant settlement with a tamper-evident audit trail and the controls regulators and operators require.
Permissioned visibility, role-based access and policy hooks, so sensitive ownership data stays with authorized parties.
Transfer restrictions, transfer agent obligations and market-integrity conditions implemented as verifiable rules rather than ad hoc spreadsheets.
Open Cap Table Format
The Open Cap Table Format is the open source capitalization data standard maintained by the Open Cap Table Coalition, a nonprofit trade organization whose members include leading U.S. securities law firms and major equity platform providers. It is the JSON model the industry uses to structure and exchange cap table data.
OCP is the onchain extension of that standard. Onchain equity records align with the data model top firms already promote, so the book of record stays compatible with counsel, transfer agents and the broader ecosystem.
What OCF carries
OCF mark from the Open Cap Table Format project, maintained by the Open Cap Table Coalition.
Adoption
Fairmint is an SEC-registered transfer agent running issuer book-entry on the Open Cap Table Protocol in production. The same open standard is available to other transfer agents and operators who want interoperable, onchain book-entry alongside their existing controls.
SEC-registered transfer agent. OCP in production for issuers.
Transfer agent planning to add onchain book-entry on OCP? Get in touch
Cap tables are the foundation of every company’s equity structure. Moving them onchain isn’t just about efficiency. It’s about making equity programmable.
History
By the late 1960s, trading volume had overwhelmed the settlement of physical stock certificates, fueling widespread fails and stress on broker-dealers. Regulators and exchanges went looking for models that would stop moving paper and instead settle ownership as book entry tied to the issuer’s official register.
In 1969, the American Stock Exchange commissioned what became known as the Rockwell Study. To cut certificate traffic, it proposed individual transfer agent depositories: a national clearing system paired with a decentralized network of transfer agent depositories, each maintaining the issuer’s register electronically and settling by debiting and crediting securities accounts on that register.
Listed U.S. equity instead converged on central depository and multilateral clearing. Outside that rail, private issuers kept the same register and transfer-agent concepts, but the capitalization record fractured across spreadsheets, PDFs and vendor silos. The networked, transfer-agent-centered book never went away. What it needed was infrastructure that could make multi-party, compliant electronic book entry practical at scale.
U.S. Securities and Exchange Commission
Concept Release on transfer agent regulations, Release No. 34-76743, December 2015.
Read the SEC releaseTo reduce the physical movement of securities, the Rockwell Study recommended the establishment of individual transfer agent depositories (‘TADs’), which was, at the time, a theoretical proposal that had not been implemented in any market. As proposed, the TAD model would have established a national clearing system together with a decentralized network of individual transfer agent depositories.
Concept releases solicit public comment on possible policy; they do not themselves adopt final rules.
Trillions in private markets depend on issuer-controlled issuance, transfer restrictions and transfer-agent obligations that do not disappear because a secondary venue or a bank portal goes live. Liquidity can move quickly; the authoritative capitalization record still has to satisfy issuers, counsel and regulators.
You can stand up electronic order matching or secondary markets; if the official book stays fragmented and off the same rails as your compliance story, you have not upgraded the system securities law cares about. The question stops being public or private, and becomes whether ownership sits on an interoperable, auditable, programmable system of record.
For partners
Transfer agents, cap table software vendors, banks and other market participants use the same open interfaces to connect their systems to OCP. Production-ready tooling by network, plus documentation and source, so your engineering team can wire issuance, transfers and reconciliation into an existing stack.
TypeScript library for product teams connecting to OCP on Canton: model issuance, transfers and book-entry reconciliation with network-level guarantees your stack can rely on.
Language · TypeScript
Partner tools get listed here as they ship. If you are scoping an integration, need a security or compliance review, or want to add a new runtime, talk to the team.
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