Software Licensing recommendations

This page describes the joint LSC/Virgo Computing and Software recommendations on the copyright and licensing of software products used to fulfill the scientific mission of the LSC and Virgo.

Introduction

It is critical to the credibility of the results published by the GW community that those results are reproducible; in order to reproduce results, both the data and the software must be freely available{{in this context, 'free' means zero monetary cost}}. Data are being made available by GWOSC, but there is no over-arching policy on the availability of software.

To this end, the joint LSC/Virgo Computing and Software groups make the following recommendations:

All software projects used to produce or validate scientific results published by the LIGO Scientific Collaboration should be made available under an open-source software license.

Throughout, we adopt all definitions laid out in the The Open Source Definition.

Approved licenses

The following licenses are approved for use based on their classification by the Open Source Initiative:

List of approved software licenses

Name	SPDX short identifier
GNU Affero General Pulic License (AGPL) version 3 (or later)	AGPL-3.0-only, AGPL-3.0-or-later
BSD 3-Clause "New" or "Revised" license	BSD-3-Clause
GNU General Public License (GPL) version 2 (or later)	GPL-2.0-only, GPL-2.0-or-later
GNU General Public License (GPL) version 3 (or later)	GPL-3.0-only, GPL-3.0-or-later
GNU Library or "Lesser" General Public License (LGPL) version 2 (or later)	LGPL-2.0-only, LGPL-2.0-or-later
GNU Library or "Lesser" General Public License (LGPL) version 3 (or later)	LGPL-3.0-only, LGPL-3.0-or-later
MIT license	MIT

If you wish to distribute software that uses a license not included in this list, please contact the Software Change Control Board to have your proposed license reviewed.