OpenFOAM is free software, meaning users have the freedom to run, copy, distribute, study, change and improve the software. Users benefit from these freedoms, which account for much of OpenFOAM’s popularity. The OpenFOAM Foundation is the copyright holder of OpenFOAM, which it licenses exclusively under the GPL. It maintains a strong legal position to enforce the licence and preserve its freedoms, by being the single owner of OpenFOAM. This requires contributors to the project to assign copyright in their OpenFOAM contributions to it, through its Contributor Agreement. Organisations with a serious commitment to free software are signing the Agreement, including CFD Direct, blueCAPE, VTT Technical Research of Finland Ltd and Intel.
Where is the Source Code? is a campaign to promote free, public distribution of OpenFOAM and software that links intimately to OpenFOAM. It is in response to a general dissatisfaction with the practice of making a modification to OpenFOAM, then promoting the benefits of the modification, without making that modification freely available to the public, often in order to sell it commercially. The campaign is simply to get people to ask “Where is the Source Code?” when modifications like this are promoted, for example after a conference presentation or in a response to a discussion on the Internet.