Re: comparison of public licenses?

On Thu, Jan 20, 2000, Nate Puri <natepuri[_at_]office.ompages.com> wrote:
>
> On Wed, Jan 19, 2000, Terry Carroll <carroll[_at_]tjc.com> wrote:
> >
> > Does anyone know of any comparison of the features of the major open
> > source licenses (e.g., the Gnu Public License, the Artistic License,
> > Netscape's and Apple's public licenses, etc.)?
>
> I would look at <http://www.opensource.org/>. All the licenses are
> present there and Bruce Perens, the webmaster, should have some good
> HOWTO type documents on the license features. You can email him
> directly as well and he is a very good source of information. I don't
> think anyone has written a law review yet on the topic; it's just too
> new. I could be wrong about that though. I plan to write something
> after the bar exam, as I have studied this pretty intensively.
>
> In a nutshell, GPL says, "if you change it, you have to submit the diff
> files back to the author."

Not quite.

The GPL requires that, for copies or modifications of licensed works distributed in binary format, you must either:

• Accompany it with machine-readable source code, under the terms of the GPL.
• Accompany it with a written offer valid for three years to give any third party machine-readable source. The price of this source may not exceed the cost of physically performing the distribution (generally read as media plus shipping).
• Provide information you received for finding sources. This option is only allowed for noncommercial distribution and other restrictions.

The GPL does not bind you to submitting your modifications to *any* specified party, unless that party is receiving a binary distribution based on the original work. You must, however, make your modifications available to anyone who asks, if choosing the second of the above options. See GNU GPL v.2 (3). Submission of modifications to the original developer is a courtesy, not a requirement.

This is distinguished from several recent "source code" licenses (neither free software nor open source), including Sun Microsystem's "SCSL" or Sun Community Source License, which mandates that any bugfixes created by any licensee must be submitted to Sun, whether or not these bugfixes themselves or derived code are distributed by the developer.

The key points of the GPL are:

• A work, and all derived works, must be licensed under identical terms to the original work. This is the "persistent" or "hereditary" nature of the GPL. No addition or subtraction from these terms is allowed. This condition is what makes the GPL incompatible with many other free software licenses.
• Distribution of copies or modifications of a work requires making sources available under one of the three terms above.
• A "work" includes source code, which includes build support.
• Various limitations of liability.

> The BSD license says, "do what you want with it but post the Regents
> of UC copyright notice." And the other licenses by the commercial
> entities are iterations of these two licenses with added ownership
> provisions.

Essentially, yes.

> The Artistic is a variation of the BSD.

No, it's a perversion unto itself. Some describe the Artistic License as a non-license, in that it carries no requirements. Larry Wall is reported to have written it to be deliberately vague, conveying an impression of relicensing requirements without actually imposing them. The Artistic License is intended to allow a broad degree of latitude in relicensing options.

> GPL = restrictive; BSD = permissive.

There's a term I've heard applied to free software licenses which I like. It describes the scope of what falls under the relicensing requirements of a license, and is somewhat apropos after last night's celestial show: penumbra.

A license which is broadly inclusive of what derived or larger works fall under it has a large penumbra. The GNU GPL would be a prime example -- its penumbra includes all works which incorporate the original (or portions) in either source, object, or runtime instance (the link-level boundary).

A license which is narrowly inclusive of what derived or larger works fall under has a narrow penumbra. The GNU LGPL and Mozilla Public License (MozPL) are examples. The LGPL is a bit fuzzy, but essentially includes only works which incorporate the original (or portions) in source form. The MozPL applies on a file-by-file basis.

A license which is non-inclusive of derived or large works has no penumbra. The (revised 1999) BSD and X licenses are examples, in that they require only a copyright notice, but do not otherwise prescribe relicensing terms.

> What is uncertain is the manners in which copyright will render one or
> more provisions of the GPL type licenses moot.

Could you expand on this?

IANAL, this is not legal advice.

-- 
Karsten M. Self (kmself[_at_]ix.netcom.com)
    What part of "Gestalt" don't you understand?

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