> It is open-source, but disallows commercial for-profit use.
The NPOSL is not disallowing commercial use, it is claiming that the source of the software is a non-profit, derives no revenue from the software (including hosting), and provides no warranty for the software.
In other words, the NPOSL has modifications from the OSL that further protect a non-profit from being sued. A judge (depending on jurisdiction) might look askance at a complete disclaimer of warranty if an implied commercial relationship can be construed between the entities that provided and used the software (for example, through a donation, or perhaps by contributing employee work).
There is probably case law of non-profits being sued for something they provided for free, the NPOSL is trying to protect against that, given that compared to for-profit companies, they are likely to be resource constrained.
Thank you for correcting that! I read the license more careful now, and you are indeed right. I confused licensor with licensee. I was wondering about it, because I thought that open-source must allow commercial use under the OSI definition.
> I was wondering about it, because I thought that open-source must allow commercial use under the OSI definition.
You thought correctly. This is usually stated as "the license may not discriminate against a field of endeavor". Besides limiting commercial use, another commonly raised desire is forbidding military or law enforcement use, but those can't be called "Open Source" either, not to mention being incompatible with the GPL.
BTW, compatibility with the GPL is a big deal even if you want a permissive license. One of the big drivers for drafting the Apache 2.0 license was that Apache 1.0 wasn't compatible with the GPL, causing quite a few headaches. Relicensing the Apache Foundation's projects wasn't too difficult, since the foundation requires copyright assignment for all contributions. OTOH, relicensing the Linux kernel from GPL 2 to GPL 3 is effectively impossible even if Linus weren't opposed to it, without tracking down all contributors and getting their permission, or replacing the affected bits of code if they (or their successors) cannot be found or refuse to cooperate.
So one thing you might consider is licensing your project as GPL 3.0 or any later version as published by the FSF, which does mean you would be trusting the FSF not to screw with the spirit of the GPL in future versions. Probably a safe bet for the next decade or two, but then again Linus didn't (and presumably still doesn't) like the changes made to GPL 3.0, so YMMV.
> It is open-source, but disallows commercial for-profit use.
The NPOSL is not disallowing commercial use, it is claiming that the source of the software is a non-profit, derives no revenue from the software (including hosting), and provides no warranty for the software.
In other words, the NPOSL has modifications from the OSL that further protect a non-profit from being sued. A judge (depending on jurisdiction) might look askance at a complete disclaimer of warranty if an implied commercial relationship can be construed between the entities that provided and used the software (for example, through a donation, or perhaps by contributing employee work).
There is probably case law of non-profits being sued for something they provided for free, the NPOSL is trying to protect against that, given that compared to for-profit companies, they are likely to be resource constrained.