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Difference between revisions of "Patent clauses in software licenses"

(mention grants in the intro)
(WebM licence: Google first published the WebM audio-video codec under a licence which had a patent grant and a retaliation clause. After some unrelated controversy,<ref>http://lwn.net/Articl)
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==WebM licence==
 
==WebM licence==
  
This is the licence used by Google for the [[WebM|VP8]] video codec, first published in May 2010:
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Google first published the [[WebM]] audio-video codec under a licence which had a patent grant and a retaliation clause.  After some unrelated controversy,<ref>http://lwn.net/Articles/389611/</ref><ref>http://lwn.net/Articles/391073/</ref> they changed to a simpler licence and a separate grant.  The text relating to patents didn't change much.  The text from the grant is:
  
* http://www.webmproject.org/license/software/
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* http://www.webmproject.org/license/additional/
  
 
<blockquote>
 
<blockquote>
''Subject to the terms and conditions of the above License, Google hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except as stated in this section) patent license to make, have made, use, offer to sell, sell, import, and otherwise transfer this implementation of VP8, where such license applies only to those patent claims, both currently owned by Google and acquired in the future, licensable by Google that are necessarily infringed by this implementation of VP8. If You or your agent or exclusive licensee institute or order or agree to the institution of patent litigation against any entity (including a cross-claim or counterclaim in a lawsuit) alleging that this implementation of VP8 or any code incorporated within this implementation of VP8 constitutes direct or contributory patent infringement, or inducement of patent infringement, then any rights granted to You under this License for this implementation of VP8 shall terminate as of the date such litigation is filed.''
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''Google hereby grants to you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except as stated in this section) patent license to make, have made, use, offer to sell, sell, import, transfer, and otherwise run, modify and propagate the contents of this implementation of VP8, where such license applies only to those patent claims, both currently owned by Google and acquired in the future, licensable by Google that are necessarily infringed by this implementation of VP8. This grant does not include claims that would be infringed only as a consequence of further modification of this implementation. If you or your agent or exclusive licensee institute or order or agree to the institution of patent litigation against any entity (including a cross-claim or counterclaim in a lawsuit) alleging that this implementation of VP8 or any code incorporated within this implementation of VP8 constitutes direct or contributory patent infringement, or inducement of patent infringement, then any patent rights granted to you under this License for this implementation of VP8 shall terminate as of the date such litigation is filed.''
 
</blockquote>
 
</blockquote>
  

Revision as of 09:55, 19 July 2010

Red alert.png What this entry documents is not a solution.
This practice may be ineffective or useless in the long term.
ESP's position is that abolition of software patents is the only solution.


Software licences can solve a small category of patent problems. They can give recipients an explicit grant of patent rights, and they can place requirements on patent holders who participate in distributing that software.

Among free software licences, the best licences to use in terms of patent clauses are GPLv3 (among the "strong copyleft" licences), LGPLv3 (among the "weak copyleft" licences), and Apache 2 (among the "permissive" licences).[1] Each of these is discussed below.

Limits to effectiveness

  1. These clauses only apply to patent holders who distribute the software which uses this licence.
  2. The stronger the clause, the less likely it is that dangerous patent holders will distribute software that uses the licence.

How to evaluate patent clauses

Good patent clauses that can be put into software licences include:

  • A grant of patent rights.
  • Retaliation - retract the granted rights from anyone who initiates litigation. This allows the distributor to use their patents to defend against aggression.
  • Indemnity - this would be great, but it's usually impractical.

GNU GPL v2

See section 6 and section 7.

Dan Ravicher argues that GPLv2 includes an implicit patent grant.[2][3]

GNU GPL v3

Note: the same patents clause exists in the: GNU Affero General Public License v3

Section 10:

you may not impose a license fee, royalty, or other charge for exercise of rights granted under this License, and you may not initiate litigation (including a cross-claim or counterclaim in a lawsuit) alleging that any patent claim is infringed by making, using, selling, offering for sale, or importing the Program or any portion of it.

Also, section 12, which is very similar to GPLv2's section 7.

Related discussions

LGPL 2.1

Apache License

The Apache License contains both a patent grant and a patent retaliation clause.

The grant is the fist half of Section 3:

Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except as stated in this section) patent license to make, have made, use, offer to sell, sell, import, and otherwise transfer the Work, where such license applies only to those patent claims licensable by such Contributor that are necessarily infringed by their Contribution(s) alone or by combination of their Contribution(s) with the Work to which such Contribution(s) was submitted.

The retaliation clause is the second half of that section:

If You institute patent litigation against any entity (including a cross-claim or counterclaim in a lawsuit) alleging that the Work or a Contribution incorporated within the Work constitutes direct or contributory patent infringement, then any patent licenses granted to You under this License for that Work shall terminate as of the date such litigation is filed.

Among the "permissive" class of free software licences, Apache 2.0 is the licence recommended by Bradley Kuhn as being the best with regard to patents.[4]

Mozilla Public License

Section 8:

(excerpt) "...if You initiate litigation by asserting a patent infringement claim (excluding declatory judgment actions) against Initial Developer or a Contributor (the Initial Developer or Contributor against whom You file such action is referred to as "Participant") alleging that..."

WebM licence

Google first published the WebM audio-video codec under a licence which had a patent grant and a retaliation clause. After some unrelated controversy,[5][6] they changed to a simpler licence and a separate grant. The text relating to patents didn't change much. The text from the grant is:

Google hereby grants to you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except as stated in this section) patent license to make, have made, use, offer to sell, sell, import, transfer, and otherwise run, modify and propagate the contents of this implementation of VP8, where such license applies only to those patent claims, both currently owned by Google and acquired in the future, licensable by Google that are necessarily infringed by this implementation of VP8. This grant does not include claims that would be infringed only as a consequence of further modification of this implementation. If you or your agent or exclusive licensee institute or order or agree to the institution of patent litigation against any entity (including a cross-claim or counterclaim in a lawsuit) alleging that this implementation of VP8 or any code incorporated within this implementation of VP8 constitutes direct or contributory patent infringement, or inducement of patent infringement, then any patent rights granted to you under this License for this implementation of VP8 shall terminate as of the date such litigation is filed.

CDDL

(See: CDDL and patents)

Related pages on ESP Wiki

External links

References

  1. "Post-Bilski Steps for Anti-Software-Patent Advocates". http://ebb.org/bkuhn/blog/2010/06/30/bilski.html. "License your software using the AGPLv3, GPLv3, LGPLv3, or Apache-2.0. [...] At least when such companies contribute code to projects under these licenses, we know those particular codebases will be safe from that particular company's patents." 
  2. http://ipmall.info/hosted_resources/sipla/sipla_2005/ravicher_slides.pdf
  3. https://www.fsf.org/licensing/seminar-materials/2005nyc/implied-patent-grant-slides.pdf
  4. "Post-Bilski Steps for Anti-Software-Patent Advocates". http://ebb.org/bkuhn/blog/2010/06/30/bilski.html. "License your software using the AGPLv3, GPLv3, LGPLv3, or Apache-2.0. [...] At least when such companies contribute code to projects under these licenses, we know those particular codebases will be safe from that particular company's patents." 
  5. http://lwn.net/Articles/389611/
  6. http://lwn.net/Articles/391073/