Open Knowledge

Open Definition

Defining Open in Open Data, Open Content and Open Knowledge


Also see a Wikipedia article about the Open Definition.

Versions of the Open Definition

v2.1: 2015-11


2.0-2.1 diff

v2.0: 2014-10


1.1-2.0 diff

v1.1: 2009-11

Very minor corrections and emendations to the text. Merge annotated and simple versions of the definition.

1.0-1.1 diff

v1.0: 2006-07

After a final period in which to solicit feedback version 1.0 was released in July 2006. At the same time the project was moved from to


Further feedback led to another minor revision (v0.2.1) in May 2006.

v0.2: 2005-10

In response to that feedback a second draft (v0.2) was released in October 2005 and publicly posted on the OKF website at

v0.1: 2005-08

The first version (v0.1) of the definition was drafted in August 2005 and was circulated to, among others, Peter Suber, Cory Doctorow, Tim Hubbard, Peter Murray-Rust, Jo Walsh and Prodromos Tsiavos.

News Items

Autumn 2009 onwards: please see Open Definition Updates and the Open Definition category of the Open Knowledge blog.