How to Select a License for Research Software 

If you want to publish your self-developed software, does it make sense to provide a certain license? Yes, of course. Which licence is the best? It is a matter of many factors.

The selection of a suitable licence for a software depends on different aspects. However, there are good arguments for assigning a license for research software. Guideline 13 in the DFG Code of Conduct explicitly states that if “self-developed research software is to be made available to third parties, an appropriate licence is provided”.((Guideline 13 in the DFG Code of Conduct “Guidelines for Safeguarding Good Scientific Practice”, The FAIR Principles for Research Software (FAIR4RS R1.1) emphasise the same. Licensing can also be interesting for commercial use (e.g. multi-licensing).

We do not recommend a certain license, but we do recommend putting an (open source) license on code, so that possible re-users are aware of what they can do with the code. There is no preferred software license in the Max Planck Society in general. The Software Licensing and Copyright Policy of the Max Planck Institute for Meteorology, for example, specifies the BSD-3 clause as a benchmark. We at Max Planck Digital Library are using CDDL for our self-developed software. Other licenses are in use in the Max Planck Society, too.

You should first clarify with your director, if it is fine to publish the research software. It is, like a paper, a scientific outcome as described in your contract. Maybe s/he also has a preference about the license.

Second, you should clarify if there are dependencies in the software, e.g. third party libraries, which require a certain license, i.e. copy left licenses like GPL. To say it again, you must consider the compatibility with already integrated third-party libraries.

Third, the following websites give you an initial overview to select the suiting license:

The DLR offers its own (German-language) publication on the use of open source licenses. It is very detailed and highly recommended for a meaningful in-depth study of the topic.

This, of course, is no legal advice. If you want to be perfectly safe, contact your local IT and law team at your Max Planck Institute. Or write to the colleagues at the Administrative Headquarter via it-recht [at] gv [dot] mpg [dot] de.