jetpacks contain MPL license

[johnjbarton]

Atul Varma and Kevin Dangoor asked me to post here.

Here is my understanding of the current jetpack addon system:
developers download a set of files called the jetpack SDK or software
development kit. They create more code and ship that code together
with the SDK as a Firefox extension. The SDK is licensed under the
MPL Mozilla public license (maybe 2.0).

Consequently everyone who creates and ships a jetpack addon has two
legal problems avoided by authors of addons that do not use jetpack:
1) They must understand and comply with the MPL license terms,
2) They must accept the liability associated with shipping the SDK
code.
Obviously different jetpack authors will evaluate these constraints
differently. Each author will weigh the costs they perceive against
the benefits they perceive. Individual developers can realistically
expect insignificant cost. Corporate developers can realistically
expect significant cost. Thus I think that the SDK model will be a
serious barrier as jetpack moves forward.

jjb

[David Illsley]

Yeah, I've been concerned about this for a while [1], but haven't had
the chance to check it out with my employers (also IBM) legal
department. I'm not expecting it to be an easy conversation,
especially because of the Tri-License [1] which mentions the GPL (and
hence enhanced attention).

For those reasons, I have avoided jetpack development at work during
recent hackdays etc.

David

[1] http://twitter.com/#!/davidillsley/status/11153404686
[2] a file picked at random...
https://github.com/mozilla/addon-sdk/blob/master/packages/addon-kit/lib/widget.js

[Kevin Dangoor]

IANAL (though I've cc'ed someone who is :), but the plain English version of the license goes like this...

1. you can opt for the GPL or LGPL if you're linking with projects that use those licenses (because the FSF said that the MPL was incompatible...)

2. most people would opt for the MPL which is the most liberal, or at least clearest in intent, of the licenses...

The MPL, in a nutshell, says that any changes *to the original files distributed* must also be released under the terms of the MPL. This is cleaner, imho, than the LGPL which talks about linking and things like that. The concept of the files that you got from the original source is pretty clear.

So, for the Addon SDK, if you don't make changes to any of the files you downloaded, you can just do whatever you want. If you *do* change some of the Addon SDK files, then you need to follow the terms of the license...

All of that said, the MPL 2.0 is in beta and is a good deal shorter and hopefully easier for people to digest.

I'd be surprised if there wasn't a lawyer at IBM already who had dissected the MPL. Finding that lawyer might be tricky though ;)

Kevin

--
Kevin Dangoor

work: http://mozilla.com/
email: k...@blazingthings.com
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