OpenAPI Initiative

The OpenAPI Initiative (OAI) is a collaborative project of the non-profit Linux Foundation. The LF announced it on November 5, 2015, as the Open API Initiative, with 3Scale, Apigee, Capital One, Google, IBM, Intuit, Microsoft, PayPal, Restlet and SmartBear, which donated the Swagger Specification it had bought that March. On January 1, 2016 the specification was renamed OpenAPI. The OAI now publishes three specifications: OpenAPI, for describing HTTP APIs; Arazzo, for workflows that chain API calls; and Overlay, for patching an OpenAPI description from a separate file. All three are under the Apache 2.0 licence.

Companies join as Participating Members, whose yearly fee depends on headcount and LF membership, from $500 for one with fewer than 10 employees that already belongs to the LF to $45,000 for one with 5,000 or more that doesn’t; open-source projects, non-profits and universities can join free as Associate Members. Each member appoints a representative to the Business Governing Board (BGB), which manages the trademarks and budget. In October 2026 the OAI’s landscape listed 17 Participating Members, among them Google, IBM, Microsoft, SAP, SmartBear, Kong, Tyk, Bloomberg, eBay and the API tool makers 42Crunch, bump.sh, Redocly and Scalar, and 11 Associate Members, including the UK government and the OpenTravel Alliance.

For someone choosing a technology, the badge covers the specification documents and their JSON Schemas, not the tools that read them. Swagger UI and Swagger Editor belong to SmartBear, OpenAPI Generator is an independent community project, and Kiota, Spectral and Redocly each belong to their companies. There are no maturity stages: the OAI has its three specifications plus special interest groups (SIGs), and anyone can join the weekly calls where changes are discussed.