The Open Definition

The Open Definition is a document published by the Open Knowledge Foundation (now Open Knowledge International (OKI)), to define openness in relation to data and content. It specifies what licences for such material may and may not stipulate, in order to be considered open licences. The definition was derived from the Open Source Definition.

OKI summarise the document as:

Open means anyone can freely access, use, modify, and share for any purpose (subject, at most, to requirements that preserve provenance and openness).

The latest form of the document, published in November 2015, is version 2.1. The use of language in the document is conformant with RFC 2119.

The document is available under a Creative Commons Attribution 4.0 International License, which itself meets the Open Definition.

The first draft of the Open Definition, v0.1, was circulated in August 2005. v1.0 was published in July 2006. v2.0 was published in October 2014.

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