Just to make it clear, I'm too in favor of adding an Apache2-like patent clause to the license.
And for the sake of full-disclosure, my employer does releases quite
a large amount of Apache-2 licensed code.
On Fri, Jan 13, 2012 at 8:34 PM, Eric Rannaud
<address@hidden> wrote:
On Fri, Jan 13, 2012 at 11:16 AM, Dave Crossland <
address@hidden> wrote:
> On 13 January 2012 20:13, Werner LEMBERG <
address@hidden> wrote:
>> I would like to add something similar, with the exception that code
>> especially marked as patented within the FreeType source code is not
>> covered.
>>
>> Comments?
>
> Why not just switch to Apache?
Switching to Apache2 is an interesting possibility, but such a license change means getting the approval of all contributors to the project. Given FreeType's age, that might be challenging and/or time-consuming (e.g. what are the chances that all email addresses in our copyright disclaimers are still valid).
An easier approach would be to ask for all future contributions to be covered by "FreeType License 1.1", which would be equal to the actual one, plus a patent clause. This allows us to keep the existing code just as-is in case we don't have a contact or agreement with the original author of some piece of code. Also makes explaining the change easier.
We can still continue to contact contributors to ask them their opinion/agreement on switching their existing code to Apache 2 though, and maybe later switch to it.
Apache2 is not compatible with GPLv2 notably because of this
particular patent clause (that's the general agreement anyway -- some
see GPLv2 as already having an equivalent clause, albeit less
explicit). Apache2 is compatible with GPLv3, however.
GPL is already not an issue since the original FreeType license is not compatible either (due to the credit clause). That's why we dual-license the library by the way. I don't see why anything would change with the proposed license update.
So you want to be careful adding that kind of exception, you may
create a number of new license compatibility questions.
If you want such a patent grant clause, you might as well have
Freetype released under Apache2 and continue to make it available
under GPLv2. At least license compatibility is then clear.
However, by switching to Apache2, or by adding such a clause, you will
likely make Freetype harder to use for some projects that may have
liked the current license better. (e.g. OpenBSD: they don't like
Apache2, and maybe would reject Freetype license + patent grant.)
I'm ok with OpenBSD rejecting an updated license (you can't please all people in the world after all). I still can't find any official reason why they're opposed to Apache2, but they can still use the existing FreeType code and back-port security fixes manually if they want. They've been doing it with Apache 1 for years and nobody's been greatly impacted by it as far as I understand.
It might be a good thing to bump the library's minor version number for the license change to make this back-tracking easier.
- David