no-liability -> liability, warranty

[mlinksva]

rename and add tag and associated descriptions

fixes #412

[waldyrious]

For convenience, quoting #412 (comment):

I thought almost all (except WTFPL) public copyright licenses have both [liability and warranty limitations], but searching the ones cataloged here, it seems MS-PL and MS-RL do not include a limitation on liability.

[mlinksva]

Thanks @waldyrious indeed I should've included that info. I also should've cc'd @richardfontana @benbalter @lee-dohm

[lee-dohm]

Looks good to me! 🎉 👍

[benbalter]

I thought almost all (except WTFPL) public copyright licenses have both [liability and warranty limitations], but searching the ones cataloged here, it seems MS-PL and MS-RL do not include a limitation on liability.

Why is it necessary to have distinct warranty and liability properties? Two reasons I ask:

1. Is it worth the added complexity to the vast majority of use cases for the incremental clarity provided for the (hidden) MP-* licenses? The fact that the MP-* licenses have a slightly weaker "don't sue me" clause (that covers contract, but not tort causes of action), seems too far in the weeds to make it worth adding the additional field to every other license. Perhaps it could be better served by a note in the sidebar clarifying the weaker protections?

2. The other limitations are liability, copyright, and trademark, and are in the negative, meaning you can't use my copyright, you can't use my trademark, and you can't hold me liable. In the case of warranty, it's that I've affirmatively disclaimed implied warranties (or that you can't bring a cause of action under one of those implied warranties, which again feels in the weeds for me... most would just call that liability, and if you need more specifics, you should get a lawyer to talk through your particular use case).

[mlinksva]

It's not necessary to have distinct warranty and liability properties. It's not necessary to have either of them. The only real outlier is WTFPL and that could be noted in its description. The MS-PL/RL difference is trivia, not a motivation for adding warranty; I only noticed in process of adding. In general we don't require variation among licenses in order to make something a tag. Indeed several permissions are mandatory in order for a license to be cataloged, ie they're the same for all licenses.

The reason for including any tag should be that it helps provide an accurate and clear description of licenses for licensors and licensees. Not necessarily a precise description, as that would entail getting into the weeds.

I agree that both limitation on liability and disclaimer of warranty serve same overall objective -- reduce potential costs to licensor and to some extent others. #412 (comment) made me think that level of abstraction might make it harder to be accurate, and harder to be clear. I guess that most people have a good intuition about what no warranty means, and I also guess that most people would not intuitively think of a warranty as a liability, simply because they've never even considered the question.

Again, I don't consider either tag really necessary here. The benefit to including either is probably to inform reader that these are issues that maybe you wouldn't have thought about, but by using a standard open source license, they are covered. For that benefit, I guess that stating both liability and warranty is better than folding them together.

I don't feel particularly strongly, happy to close this without merging if above is nonsense. 😄

[mlinksva]

I'm going to merge this in the next few days if I don't get other feedback. I'm somewhat attracted to not modeling limitations at all (explicit tm and patent non-permissions could be modeled as such) but that would be a bigger change and I think there's some benefit to calling liability/warranty limitation/disclaimer as a feature of most open source licenses.