GPLv3 hits 50 percent adoption

In July 2007, version 3 of the GNU General Public License barely accounted for 164 projects. A year later, the number had climbed past 2,000 total projects. Today, as announced by Google open-source programs office manager Chris DiBona, the number of open-source projects licensed under GPLv3 is at least 56,000.

And that's just counting the projects hosted at Google Code.

In a hallway conversation with DiBona at OSCON, he told me roughly half of all projects on Google Code use the GPL and, of those, roughly half have moved to GPLv3, or 25 percent of all Google Code projects.

With more than 225,000 projects currently hosted at Google Code, that's a lot of GPLv3.

If we make the reasonable assumption that other open-source project repositories Sourceforge.net and Codehaus have similar GPLv3 adoption rates, the numbers of GPLv3 projects get very big, very fast.

The data becomes even more significant, however, when you consider the number of active projects on Google Code, Sourceforge, and elsewhere. Google's ratio of active projects is much higher than Sourceforge's, which generously sees maybe 12 percent of its total number of projects under active development.

Hence, even if GPLv3's overall numbers may still seem small compared with GPLv2, its share of active projects may be quite large.

My recent flirtations with Apache-style licensing notwithstanding, clearly there's life remaining in the GPL, and particularly Version 3.

Follow me on Twitter @mjasay.

[t8]

Can GPL3 code be used in GPL2?

e.g., Linux is GPL2. Can GPL3 code be used?

[The_Decider]

Your question makes no sense.

Yes GPL3'ed code can run on linux, just like proprietary can run on Linux. Can it be included in the kernel? Probably not.

These are two completely separate concepts, hence your question is nonsense.

[odubtaig]

Unclear? Yes. I wouldn't be so harsh as to call is nonsense.

I think what's being asked is whether code from one can be use in the other.

If code is released under GPLv2, only if it is specifically stated that this code can be used with later license can it be used in GPLv3 licensed code. At the time GPLv3 was finalised, Linux was released under GPLv2 _only_ which prompted a lot of 'discussion' as to whether it could ever be moved to GPLv3 even if Torvalds and the primary community wished to do so due to contributed code possibly being owned by missing or deceased persons.

GPLv3 code cannot be used in GPLv2 licensed projects. There is no backwards compatibility. This is mainly because allowing this would defeat the point of a number of the changes made for GPLv3 which were designed to close loopholes present in GPLv2.

The only legal way around this is to acquire agreement from all original authors or copyright holders of the code in question for them to re-release the code under a new license.

In short:

If I release code under GPLv2 or above you can use it with GPLv2, 3 or 500 if you like, but not GPLv1.
If I release code under GPLv2 only, you can use it with GPLv2 only.
If I release code under GPLv3 or above you can use it only with GPLv3, 4, whatever but not GPLv1 or 2.
If I release code under GPLv3 only, you can use it with GPLv3 only.
I, on the other hand, can use this code under whatever license is convenient to me so long as this does not affect other people's copyrighted work, so if I release it under either of the above licenses, I can still release it under BDS, MIT, proprietary commercial, or any other license.

[odubtaig]

Yes, I meant BSD (I'll be calling it IBS next).

[aatinko]

Wow, that is just too cool. Good to see people care.
[CNET editor's note: Prohibited self promotion deleted.]

[kevinchin5]

Earlier this month (http://news.cnet.com/8301-13505_3-10276903-16.html) you referred to a Black Duck study which shows the GPL v3 is only at around 5% adoption. Less than a month later it's up to over 50%? Somebody's data is not adding up wouldn't you say... Am I missing something?