OpenIFS is currently licensed software. Although the intention for the future is to provide a less restrictive license, this requires approval by ECMWF Council and due process. For the moment, OpenIFS is licensed per institution and requires signatures from both ECMWF and the host institution. This should not be seen as a barrier to use of OpenIFS.
We also provide a contributors license for code written by users that we would like to include in OpenIFS or IFS.
For more details, please email: openifs-support@ecmwf.int, or you can phone ECMWF and ask to speak to Glenn Carver (OpenIFS project manager).