[License-review] BSD-based anti-patent license

[John Funnell]

Dear license-review,

GPL v2 has a patent retaliation clause. The way I understand it, it is
a neat way to make a strong anti-patent statement, effectively giving
a licensee three options:
- redistribute our code, but don't arrange any patent license for it
- redistribute our code and arrange a patent license for all possible
downstream recipients
- don't redistribute our code at all.

[If my understanding of GPL v2 is not quite accurate, please don't
dispute at length here, I want to focus on a new license.]

I really like this model but would also like cover the case where a
recipient decides to procure a patent license from a third party for
his own use. I would like anyone believing my code infringes on some
patent to have three similar choices:
- use our code, but don't arrange any patent license for it
- use our code and arrange a patent license for all possible users of our code
- don't use our code at all.

This shares the intentions of GPL v2, that is, it is not intended to
encourage people to infringe patents. Rather, the application of this
license to a popular project would be a strong anti-patent stance
which may even encourage patent holders to loosen their grip and offer
free licenses. Or for a philanthropic and PR-minded company to buy or
license patents to support free software usage.

The license itself is very straightforward. It's just new-BSD with an
extra clause, reproduced below. It may well be possible to reword this
to be more effective or clearer.

I have three questions:

1. Is this OSI compliant?
2. Does the license work as intended, i.e. preventing people
redistributing or using the software if they procure a patent license
only for themselves or only for a subset of recipients?
3. Is the extra clause so broad, vague or scary such that it might put
off potential non-patent-licensing users?

Looking forward to OSI acceptance,

John



Copyright (c) <year>, <copyright holder>
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

    [ three standard new-BSD conditions not shown here]

    * No patents are licensed from any third party in respect of
      redistribution or use of this software or derivatives unless the
      patent license unconditionally permits anyone worldwide to
      distribute, redistribute and use this software and derivatives.

THIS SOFTWARE IS... [standard BSD disclaimer not shown here]