[conspire] Chess pictures, licensing, and the law of "derivative works"
rick at linuxmafia.com
Fri Jan 16 14:46:11 PST 2009
Eric de Mund has invited me to give a licence analysis of issues raised
by a set of X11 pixmaps he's created for chess software. An author of a
chess program (whom we'll call "D.") has requested that Eric not use GPL
(or, impliedly, any other copyleft licensing for his pixmaps, because D.
would like to use them in a chess program issued under one of the BSD
family of licences.
D. believes GPL licensing for those image files to create licence
incompatibility; hence his request to Eric. (I'm assuming and hoping
Eric will forward my comments back to D.)
First, I commend both of you for caring enough to be careful about
licensing. Licence incompatibility is a lingering trap in both free
/ open source _and_ proprietary software, that can create big problems
later on: It can lead to distributors and reusers of those works
inadvertantly committing copyright violation. Also, my thanks to D. for
his generosity in making his work available under permissive licensing.
D.'s concern is that he or a subsequent distributor of his work, if it
incorporates Eric's pixmaps, would be held to violate Eric's copyright
and thus be a tort, subjecting that person to tort damages and remedies.
Why? Because of violation of the copyleft clause. _If_ violation occurs,
which is often not the case -- but we'll get back to that.
Before I go further, I need to explain about the concept of "legal
advice", because by law in this and other countries, only an attorney
may give (or sell) it to you: Legal advice is the act of giving a
formal opinion about how the law correctly applies to someone's real
legal situation. That is a regulated monopoly; I cannot lawfully do
that for you or anyone else, because I am not a lawyer.
However, the law recognises a clear distinction between legal advice and
legal information: All of us have a strong incentive, and even
citizen's duty, to have some understanding of law: We're in situations
with legal aspects literally all the time, and we actually _make_ laws
(by initiative statute) and elect representatives who make them. So,
our right to discuss, write about, and understand the law is protected:
We just may not advise others about their specific legal problems.
In California, unauthorised practice of law is a misdemeanor punishable
by up to 90 days in jail and a $1000 fine. Naturally, people _do_
tend to frequently give others casual advice and not get prosecuted, but
it's a bad habit.
So, while I cannot (lawfully) tell you and D. how the law applies to
your situation, I certainly can talk about application of copyright law
to situations involving BSD (/permissive) and GPL (/copyleft) elements
in works, generally.
Here's the nitty-gritty: People get spooked by a somewhat grandiose
clause in GPLv2 (clause 2) and GPLv3 (clause 5) that appears to give it
awesome magical powers to over other people's property adjoining the
covered work. In GPLv2:
You must cause any work that you distribute or publish, that in
whole or in part contains or is derived from the Program or any
part thereof, to be licensed as a whole at no charge to all third
parties under the terms of this License.
You must license the entire work, as a whole, under this License to
anyone who comes into possession of a copy. This License will therefore
apply, along with any applicable section 7 additional terms, to the
whole of the work, and all its parts, regardless of how they are
packaged. This License gives no permission to license the work in any
other way, but it does not invalidate such permission if you have
separately received it.
There is, it turns out, a great deal of FSF bullshit hidden in that
wording, because GPL (like other licences) has no such power, because
it has no such reach. In choosing a licence for an instance of a
creative work, an author (copyright owner, actually) is expressing his
requirements for redistribution of his/her property and and the creation
and distribution of _derivative works_ of his/her property. Inherently,
a licence's reach cannot extend beyond derivative works.
The question then is: What _is_ a derivative work? This is a term of
art, i.e., a technical term with a defined meaning, within copyright
Unfortunately, it's defined mostly through a large body of caselaw.
Generally speaking, for one work to be derivative of the other, it must
borrow major, copyright-protected elements of the other work and
incorporate them in some very substantive way. Merely using the work
and referencing it does not, per se, incorporate it.
Again, FSF tends to assert that dynamic linking codebase A to library
code B inherently makes work A a derivative of work B, but this is
I would say it's really clear that, to pick an artful example, a program
author choosing to use a set of sound files that are under a different
and incompatible licence does _not_, in itself, make the program
derivative of the sound files under copyright law. As long as the
author respects the separate licence terms of the sound files, he/she
has committed no tort, nor would any downstream redistributors. Just
putting the sound files in with the program and playing them, just like
including picture files with a program and displaying them, simply isn't
the sort of "reuse" that is intended by the legal term "derivative work".
It is sometimes alleged that the cited "You must cause..." clause causes
BSD-licensed code to get "infected" by GNU GPL obligations, if both BSD
and GPL-covered code are used in a project. This, too, is bullshit.
If it were true, then both Oracle Corporation and IBM Corporation would
already have had their Oracle RDBMS and DB/2 databases "tainted" by GPL
code they use and ship. Which of course they don't. So, this fear,
often heard in the BSD community [***COUGH*** Darren Reed ***COUGH***]
[***COUGH*** Brett Glass ***COUGH***] is rubbish.
In particular, the allegation that any infringement of GPL terms
that _does_ occur obligates the infringer to reissue his/her own code
under GPL, is simply not how copyright tort law works: If I'm ruled to
have violated your copyright (say, by creating a derivative of your
GPL-licensed work and then issuing it under proprietary licensing), then
I can be obliged to pay you statutory and actual damages (actual
financial losses you can prove to the court) and ordered to cease
infringing. That's it. The court cannot and does not order me to do
anything with _my_ property. It is concerned solely with what I may do
with _your_ property.
Last, BSD is a _family_ of licences. Only the older forms of that
licence, the ones with the famous "advertising clause" that basically
aren't used any more, clash with GPL in derivative works (_if_ what
one is creating is a derivative work at all). So, works under the newer
BSD licence -- the one actually in use for the last decade -- should
have no legal problems whatsoever from using GPLed anything. The two
are simply not incompatible licences. The people who say so are
I hope my very brief discussion of derivative work law is useful.
It's regrettable that I cannot advise you on the specifics of your
situation, but you can and should figure out for yourself how the legal
information I outline might apply to your case.
One last thing: You referred in your note to D. to the Merida and Alpha
fonts being "freeware". Unfortunately, the latter is a meaningless
term, when you're referring to licensing. We seem to have inherited
that term from the world of proprietary software users, where the main
obsession is over whether one can acquire and use something without
charge ("free"), without regard to whether it is lawful or not.
I notice that Merida's available at
Looking inside the archive, I see no licence statement whatsoever.
According to copyright law, the rights to redistribute and make
derivatives of a copyright-covered work rest by default with the
copyright owner. They are "reserved" rights: If the owner doesn't
grant them explicitly when he/she issues an instance of his/her
copyrighted property, then they're not given out. Period.
(Copyright law permits issuing licences in writing, orally, or through
conduct, so it would in theory suffice for someone to prove that the
Merida author nodded when asked "Do you grant people the right to
redistribute Merida and make derivatives of it?" But I see no such
permission grant, at first glance.)
I notice there's a great deal of that among the chess fonts on
http://www.enpassant.dk/chess/fonteng.htm : It's asserted to be
"freeware", and upon examination there's no indication of a licence at
all. This unfortunately is really typical of a lot of works casually
traded on the Internet: In many cases, the author assumed that, if
he/she merely uploaded a work somewhere, he/she is implying permission
to redistribute at will. That is not the case by law, however.
In practice, even though the result is technical copyright violation,
generally speaking nobody cares. The author _could_ object and enjoin
or get damages, but doesn't. The entire area of "abandonware" exists on
this sort of turning of a blind eye to copyright violation. So does a
great fraction of the material on YouTube, for example.
If your friend D. is looking for legal issues he -should- worry about
with his chess program, he might have a good, hard look at those fonts.
 Technically, only a _lawyer_ may give legal advice. The term
"attorney" means "someone who represents someone else in a legal
capacity". Someone who has passed the bar examination becomes a lawyer
by doing so, but becomes an attorney only subsequently by representing
clients. That is, "lawyer" is a professional qualification, while
"attorney" is an occupational role. Note that there are also a few
types of attorney roles that non-lawyers are permitted to perform, e.g.,
someone empowered to act as someone else's agent is said to be that
person's "attorney-in-fact". See:
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