That license looks like an extended BSD license. Please add it to the according groups.
@Licenses team: Does this qualify as a free software license? It is 3-clause BSD with the following added clause: 4) This license shall terminate automatically and you may no longer exercise any of the rights granted to you by this license as of the date you commence an action, including a cross-claim or counterclaim, against the copyright holders or any contributor alleging that this software infringes a patent. This termination provision shall not apply for an action alleging patent infringement by combinations of this software with other software or hardware. I think this termination clause is problematic. Especially, will any downstream parties, e.g. who have received a modified version, have their licenses terminated, too?
I don't think it's a free licence. It's terminated if you "commence an action against" them. Just what does that means? I don't know, they refuse to tell me. This serves as yet another proof of why people shouldn't write their own licences.
Closing then. If this is to be added to one of the free software groups, ask upstream to have their license approved by the FSF or the OSF. Or alternatively and preferably, they should release their software under one of the existing free software licenses.
This is what upstream says. Any additional thoughts? Justin, The UDUNITS package is intended to be FOSS. Both GitHub and a license-person at the Free Software Foundation agree that it is. The anti-software-patent clause in the UDUNITS license is similar in intent to the following (from which it was adopted and adapted): Section 7 of "Common Public License Version 1.0" Section 7 of "Common Public License, version 1.0 (CPL-1.0)" Section 7 of "IBM Public License Version 1.0 (IPL-1.0)" Section 8 of "Lucent Public License Version 1.02 (LPL-1.02)" Section 7 of "Lucent Public License, Plan 9, version 1.0 (LPL-1.0)" Clause 3 of "Apache License, Version 2.0" Clause 3 of "Educational Community License, Version 2.0 (ECL-2.0)" Clause 11(c) of "RealNetworks Public Source License Version 1.0 (RPSL-1.0)" Clause 10 of "The Non-Profit Open Software License version 3.0 (NPOSL-3.0)" Clause 10 of "The Open Software License 2.1 (OSL-2.1)" Clause 10 of "The Open Software License 3.0 (OSL-3.0)" Clause 10 of "Academic Free License 3.0" Clause 13 of "Artistic License 2.0" Section 7 of "Eclipse Public License -v 1.0" Section 7 of "Eclipse Public License 1.0 (EPL-1.0)" Clause 8 of "Computer Associates Trusted Open Source License 1.1 (CATOSL-1.1)" Section 10 of "GNU AFFERO GENERAL PUBLIC LICENSE, Version 3 (AGPL-3.0)" Section 10 of "GNU General Public License, version 3 (GPL-3.0)" Clause 6(E) of "Adaptive Public License 1.0" All the above can be found at the Open Source Initiative <https://opensource.org/search/node/cross-claim>. The bug-report you referenced appears to indicate that we were asked about this before and refused to answer. I don't recall being asked about this (I'm the only developer and support person for the UDUNITS package). Please feel free to continue this interesting conversation.
Debian also have doubts about the freeness of the patent action clause, e.g. for the AFL-2.1 and the OSL-2.0: https://lists.debian.org/debian-legal/2004/10/msg00237.html https://lists.debian.org/debian-legal/2004/05/msg00118.html Our @FSF-APPROVED and @OSI-APPROVED license groups list licenses approved by (the lawyers of) the FSF and the OSI. In addition, for practical reasons we have the @MISC-FREE group, which lists licenses where we think that they conform to the Free Software Definition. However, as we are not lawyers ourselves, we tend to add only the obvious cases to @MISC-FREE. (In reply to Justin Lecher from comment #4) > This is what upstream says. Any additional thoughts? > > Justin, > > The UDUNITS package is intended to be FOSS. Both GitHub and a license-person > at the Free Software Foundation agree that it is. > > The anti-software-patent clause in the UDUNITS license is similar in intent > to the following (from which it was adopted and adapted): > [...] Then I don't understand why upstream don't release their software under one of the existing FOSS licenses. (For example, Apache-2.0 may be a good choice for what seems to be intended here, and is approved by both FSF and OSI.) License proliferation is bad: https://en.wikipedia.org/wiki/License_proliferation