restrictions on web service linking?

Matthew Flaschen matthew.flaschen at
Mon Nov 20 05:00:22 UTC 2006

Clark C. Evans wrote:
> This "proprietary platform" category of free rider is particularly
> important from a moral perspective.  The value of one's database (or
> more generally, programming language or operating system)

A database is not a programming language or operating system.  I think
you're offbase in viewing databases as software.  They are inherently
data, and thus can be manipulated by multiple programs.  Attempting to
limit this to open source programs limits the freedom of the data (the
copyright of which may belong solely to the user).

> By writing software
> which is then easily ported to those platforms, one quite directly supports
> proprietary platforms without reasonable "return" to the community.

This is in accordance with fundamental copyright principles.  These
platforms (languages, databases, etc.) are not derivative works of your
software; their licensing is independent of your software's.  Even the
GPL (a license which is deliberately very demanding on redistributors)
underscores this by stating, "Thus, it is not the intent of this section
to claim rights or contest your rights to work written entirely by you;
rather, the intent is to exercise the right to control the distribution
of derivative or collective works based on the Program." It seems you're
trying to slip around this principle (fundamental to copyright law) by
limiting the user's right to use proprietary and open source software
together (since you can't limit proprietary software itself).  Thus, the
user is being limited (perhaps permanently, if their database is
tainted) because of the licensing choices of software developers they
may be unable to control.

> By analogy, suppose that I have a program that is released under the GPL
> which statically links to a particular graphics library (also GPL'd).
> One is forbidden from replacing the graphics library with a proprietary
> equivalent since it would violate the GPL.

This is because the library is a derivative work under copyright law (by
most interpretations) from the GPL software.

> In the same way, I'd like a
> clause which prevents a service upon which I'm depending from being
> replaced with a proprietary alternative.
> The GPL license comes tantalizingly close to this problem,
> were it that platforms were always statically linked. addressing  I see the use of
> sockets and other dynamic linking mechanisms as a weak spot of this
> license; one which prevents it from being enforced as intended.  I
> realize that the GPL has a particular exception for operating system
> libraries, but this was a matter of practicality, IMHO, not of intent.
> My previous attempt at a clause for this case was summarily shot down by
> Michael Poole and Matthew Flaschen, who both quoted #6 "Discrimination
> against Fields of Endeavor".  I personally don't see the problem, since,
> in my mind, the actual distinction is licensing -- which has historically
> been fair game.

Licensing use restrictions are not "fair game", as shown by OSD #9,
"License Must Not Restrict Other Software."  The section states,

"The license must not place restrictions on other software that is
distributed along with the licensed software."  It goes on to add as a note

"Yes, the GPL is conformant with this requirement. Software linked with
GPLed libraries only inherits the GPL if it forms a single work, not any
software with which they are merely distributed."

Whether it is a single work is determined by copyright law, and IANAL,
but I strongly believe that neither a database nor a platform would be a
derivative work of a program that used them.

However, you suggest:

"Let us define "Arrangement" as the static or dynamic combination of
this Original Work and its Derivative Works with other software systems
which together form a whole.  This could be accomplished through (a)
static linking, (b) dynamic linking, (c) requests done over a network
connection, (d) or any other mechanism which causes the Original and its
Derived Works to directly or indirectly control the operation of another
software system."

This goes so far beyond static linking that if a shell were under such a
license, every program distributed with it would have to be under the
same license.  Also, network applications like Firefox (if they were
under this license) couldn't communicate with servers that used
proprietary software.  Clearly, OSD #9 is intended to prevent such

Matthew Flaschen

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