Hi,

I've been reviewing the DFSG team's history for mumps and we have a serious problem with the CeCILL-C license. As Andrew Mitchell pointed out in his recent review (https://dfsg-new-queue.debian.org/reviews/mumps), this license is not compatible with the Debian Free Software Guidelines. While the package was accepted for now to avoid immediate disruption, its presence in main is a DFSG violation that must be resolved.

You need to contact upstream immediately to negotiate a move to a standard DFSG-free license like LGPL-2+ or to see if they can provide a version of CeCILL-C that actually meets our guidelines. If upstream is unwilling to relicense, the package cannot remain in main and must be moved to non-free.

The question about CeCILL-C has been raised, but we don't have a
definitive declaration confirming incompatibility and requiring the
package to be ejected from Debian.  Let's not set the bug RC critical
before then.

The home of the licence is https://cecill.info/
( https://cecill.info/index.en.html )

FSF acknowledges CeCILL-C as Free,
https://www.gnu.org/licenses/license-list.html#CeCILL-C
We are not talking about a non-free licence here.

It is known to be GPL incompatible.
But that is not the same as LGPL incompatible.