Canonical has updated the intellectual property rights policy for Ubuntu Linux to address a brouhaha over how the software is licensed, but free software advocates still aren't satisfied.

The Free Software Foundation (FSF) and the Software Freedom Conservancy (SFC) have been bickering with Canonical since 2013 over concerns that certain clauses of the Ubuntu IP rights policy seemed to claim to override provisions of the GNU General Public License (GPL) – something the GPL explicitly forbids.

On Wednesday, Canonical published a new version of the policy that the FSF and SFC has resolved this central issue satisfactorily, but the advocacy groups say there are still other issues to address.

"While the FSF acknowledges that the first update emerging from that process solves the most pressing issue with the policy ... the policy remains problematic in ways that prevent us from endorsing it as a model for others," the Richard Stallman-founded group said in a statement.