The Open Source Initiative (OSI) is the organization that has stood at the center of the open source movement since its earliest days. In its own words, it is “a non-profit corporation with global scope formed to educate about and advocate for the benefits of open source.” The organization describes itself as a California public benefit corporation with 501(c)3 tax-exempt status, founded in 1998.
OSI grew directly out of the moment when the “open source” label was first adopted. After a February 3, 1998 strategy meeting in Palo Alto where the term was chosen, Eric Raymond and Bruce Perens jointly founded the organization in late February 1998. By OSI’s own history, Raymond served as the first president and Perens as vice-president, with an initial Board of Directors that included Brian Behlendorf, Ian Murdock, Russ Nelson, and Chip Salzenberg.
The organization’s defining role is custodianship of a single document. As OSI puts it, one of its “most important activities is as a standards body, maintaining the Open Source Definition for the good of the community.” Software is not “open source” by OSI’s lights simply because its source is visible; it must be distributed under a license that satisfies every clause of the Open Source Definition.
To make that determination concrete, OSI runs a license review process and maintains the Open Source Initiative Approved License trademark program. OSI frames this approval mark as creating “a nexus of trust” that lets developers, users, corporations, and governments cooperate on open source software with confidence that the license behind a project actually grants the freedoms the label promises.
Beyond standards work, OSI positions itself as “the leading voice on the policies and principles of open source,” engaging in education, community building, and public advocacy. That combination of a precise technical definition with sustained advocacy is what allowed “open source” to move in a few years from a coined phrase into the default vocabulary of the software industry.