What Is the History of the SmartBear Swagger Acquisition?

What Is the History of the SmartBear Swagger Acquisition? #

Swagger’s journey from an internal Wordnik tool to an industry-standard specification didn’t stop with its creator, Tony Tam — see Who Created Swagger? for that origin story. The next major turning point came in 2015, when SmartBear Software acquired the project and, within the same year, set in motion the process that would turn it into the vendor-neutral OpenAPI Specification. Here’s a detailed, source-linked timeline of how that happened, who was involved, and what changed as a result.

From Wordnik to a Standalone Project #

Tony Tam built the first version of Swagger in 2010 while he was CTO of Wordnik, and the project was open-sourced soon after. As Swagger’s popularity grew well beyond Wordnik’s own API, the specification and its tooling (Swagger UI, Swagger Editor, Swagger Codegen) effectively became a project of Wordnik’s parent company, Reverb Technologies, rather than a piece of internal tooling. That set the stage for what came next: a dedicated company acquiring the project outright.

March 2015: SmartBear Acquires the Swagger Project #

In March 2015, SmartBear Software — a Massachusetts-based company known for software quality and API testing tools such as SoapUI and ReadyAPI — acquired the open-source Swagger API specification from Reverb Technologies, Wordnik’s parent company. The move gave SmartBear stewardship of the Swagger specification and its surrounding open-source tooling, positioning the company to invest directly in Swagger’s growth rather than relying on a side project at an unrelated dictionary company.

This acquisition is documented in the “History” section of the OpenAPI Specification Wikipedia article, which cites SmartBear’s own announcement, “SmartBear Assumes Sponsorship of Swagger API Open Source Project,” as the primary source for the March 2015 date.

September 2015: Tony Tam Joins SmartBear #

Six months later, on September 28, 2015, Tony Tam formally joined SmartBear as the company’s Vice President of Products, dedicating himself full-time to Swagger and the broader API tooling strategy. SD Times covered the move in an article titled “Swagger creator joins SmartBear”, which included a quote from Doug McNary, CEO of SmartBear at the time:

“Tony Tam brings his unique vision for Swagger and his passion for the API industry to SmartBear, which will help the company bring forward not only our open-source strategy, but our API tools strategy as a whole. He is a well-respected expert in the API industry, and we’re excited to have Tony’s knowledge and enthusiasm on the SmartBear team. The combination of Tony Tam and Ole Lensmar, creator of SoapUI, gives SmartBear a true brain trust in the space of open-source API tools.”

That quote also names Ole Lensmar, the creator of SoapUI who joined SmartBear through its 2011 acquisition of Eviware and later became the company’s Chief Technology Officer. Tam himself was quoted in the same piece: “For the first time since Swagger began in 2011, I am dedicating 100% of my time to it and am excited to see the next stages of growth and maturity evolve for the API industry.”

November 2015: Donating Swagger to a Neutral Home #

Owning Swagger outright raised an obvious tension: a single vendor controlling the specification that much of the API industry depended on. SmartBear resolved this in November 2015 by announcing that it would donate the Swagger Specification to a brand-new organization, the OpenAPI Initiative (OAI), operating under the sponsorship of the Linux Foundation.

According to the OpenAPI Initiative’s own FAQ, the founding members announced alongside SmartBear were:

This lines up with the OpenAPI Specification Wikipedia entry, which describes the same founding roster and cites the Linux Foundation’s original November 2015 announcement, “New Collaborative Project to Extend Swagger Specification for Building Connected Applications and Services.” Placing governance under the Linux Foundation was a deliberate choice to make the specification’s future vendor-neutral, so that no single company — including SmartBear — would unilaterally control its direction.

January 2016: Swagger Specification Becomes the OpenAPI Specification #

The donation became official on January 1, 2016: the Swagger Specification was renamed the OpenAPI Specification (OAS) and moved to a new home on GitHub, OAI/OpenAPI-Specification, where it continues to be developed today. From that point forward, “OpenAPI” refers to the specification itself, while “Swagger” refers to SmartBear’s suite of tools (Swagger UI, Swagger Editor, Swagger Codegen, SwaggerHub) that implement and support it — a distinction covered in more depth in What Are the Differences Between Swagger and OpenAPI?

Growing the Initiative #

The OpenAPI Initiative expanded quickly in the years that followed:

2016: Apiary — the company behind the competing API Blueprint format — joined the OAI and added OpenAPI support, as announced in its blog post “We’ve got Swagger”. Around the same time, SmartBear CTO Ole Lensmar published an “OAI Update” on the new members joining and early progress toward OpenAPI 3.0.
2017: MuleSoft, the company behind RAML (RESTful API Modeling Language), also joined the OAI and added OAS support — a consolidation covered by InfoQ in “The HTTP API space is Consolidating around OAS.”
July 2017: The OAI released OpenAPI Specification 3.0.0, the first major version developed entirely under the initiative’s open governance rather than by a single company.

As a side note on SmartBear itself: in May 2017, private equity firm Francisco Partners acquired a majority stake in SmartBear in a deal reported by the Wall Street Journal at around $410 million. That transaction changed SmartBear’s ownership structure but did not affect the OpenAPI Specification, which by then was already governed independently by the OAI under the Linux Foundation.

Swagger vs. OpenAPI Today #

Today, SmartBear continues to develop and sell the Swagger family of tools — SwaggerHub, Swagger Inspector, and Swagger Codegen among them — while the OpenAPI Specification itself is developed collaboratively by the OpenAPI Initiative, now with dozens of member organizations. SmartBear remains one of those members, but it no longer owns the specification outright. This split — a single vendor’s tools built on top of a vendor-neutral, Linux Foundation-governed standard — is the direct result of the acquisition and donation described above.

Watch and Read More #

For a detailed, if unofficial, recap of how the specification moved from a company-owned project to an open standard, the OpenAPI Initiative’s own FAQ points to the talk “Bridging Systems and Subcultures: A Swagger Origin Story”. For Tony Tam’s own first-hand account of Swagger’s creation and his perspective on where OpenAPI is headed, see the interview with Kin Lane, The API Evangelist, also referenced in Who Created Swagger?

Additional primary sources for this timeline:

Conclusion #

SmartBear’s March 2015 acquisition of Swagger from Reverb Technologies, Tony Tam’s move to the company that September, and SmartBear’s November 2015 decision to donate the specification to the newly formed OpenAPI Initiative together mark the transition of Swagger from a single company’s open-source project into the vendor-neutral OpenAPI Specification the industry relies on today. Understanding this history helps explain why “Swagger” and “OpenAPI” are related but no longer interchangeable terms, and why the specification’s governance sits with the Linux Foundation rather than any one vendor.

Last updated on August 14, 2026.