Open Cap Table Format

The Open Cap Table Format (OCF) is a JSON-based open-source standard for storing and sharing cap table data. We use OCF to store data off chain. The format is maintained by the Open Cap Table Coalition. You’ll find the OCF modules in the root folder:

OCF Terminology

The Open Cap Format uses specific terminology:

• Stakeholder: An equity holder on the cap table (shareholder). Can be an individual (person) or institution (company/fund).
• Issuer: The company whose cap table is being tracked.
• Security: A specific equity position (shares, options, warrants, convertibles).
• Transaction: Events that modify the cap table (issuances, transfers, cancellations, etc.).

Note that “stakeholder” in OCF context is more specific than the general business term—it refers only to equity holders, not all parties with interest in the company.

How TAP Uses OCF Offchain

OCF defines the JSON shapes TAP uses for offchain records. The API routes on this site use those shapes for issuers, stakeholders, stock classes, transactions, and supporting records.

Use the Cap Table API guides for the routes you can call today. If you want the raw field-by-field reference, the generated schema docs live under ocf/docs/schema_markdown.

Our Database

TAP stores OCF-shaped records in a database layer. Also found in the root folder, our db schema and the server: