[wp-hackers] Re: Removal Of Over 200 Themes?

DD32 wordpress at dd32.id.au
Sat Dec 13 02:18:14 GMT 2008

I'm not a lawyer, Feel free to correct me if i'm wrong.

2008/12/13 Jacob Santos <wordpress at santosj.name>

> What is the technical definition of a derivative work in layman's terms?

A Derivative work is a work which cannot exist without the GPL'd parent,
WordPress Themes and Plugins are Derivative works since they do not function
without WordPress (They -must- call things like add_action() and
add_filter() in order to work (for plugins), Or they' call WordPress
Template functions (themes)

The GPL makes more sense for compiled items, It can be a bit harder to apply
it to interprated languages such as PHP, but it remains the same once you
decide how you define certain terms of the license, Its still being debated,
But a consensus among some people, has come to the conclusion that Its
Derivative if it cannot operate seperate from the GPL project by itself
(This is the interpratation that I personally believe, but this isnt about
my thoughts). Another group of thinkers, base the fact that a Plugin or
Theme is NOT a derivative work due to the item using the API provided(ie.
template functions, *_filters, *_action) and therefor while linking to, it
does not actually access directly, or something.. Something about WP calling
the plugin/theme, and not the theme calling WP, That school of thinking
mearly didnt make sense to me, thus my POV.

> Why is a theme considered a derivative work of WordPress, if it is
released separately, but dependent on WordPress?

Because it relies upon WordPress, A Derivative work does not need to be
distributed with the parent, mearly rely upon it.

> People keep saying GPLv2, but why couldn't I release my code new BSD?
I dont have any opinion on this, As i do not know anything about the BSD

> I do release my code new BSD, the HTTP API would also be new BSD, if I had
caught it quick enough. I suppose the issue now is that I would need
permission from Ryan and DD32 + plus a couple of others in order to change
the license. The HTTP API can be used separately from WordPress, with a few
modifications to remove the wp_option code.

Since it relies upon apply_filters() and get_option(), etc, WordPress
function, It'd need to stay GPL-Compatible, I'm not sure if this means it
would have to allways be GPLv2 or whatelse, But dual-licenced code is

Now, So, How to commercial projects such as (using this as a pure example)
Bad Behaviour still operate as plugins (legally)?
Bad Behaviour is a 2 step process, Theres the core library (Which is not GPL
compatible AFAIK), and then theres the WP plugin, The plugin is dual
licenced to GPL and something else (BSD I suspect?), The Plugin relies upon
WordPress and the BH Library (So it must be GPL), The BH library, Does not
rely upon WP at all, Infact, It never calls anything in WordPress directly.
The plugin is the part that does the work, It accepts data from WordPress,
Calls the BH library if need be, and returns the result back to WP, That way
BH is never directly relying upon WordPress, and therefor, can be

This is all an AFAIK, The problem with licenses, Is that the majority of us
are not lawyers, and while we think we may understand the license, that
doesnt mean we do; Until its tested in court properly, I dont think there
will be anything to base it off..

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