I've downloaded a WordPress Theme which has a GNU licence. I have to modify it a great deal to really make it suitable for my website.

So how exactly does the certification focus on this? The initial were built with a "Created by X" within the footer however I've made changes, I am sure they will not wish to seem like they produced it anymore because it is different then the initial.

Should I only say "with different design by X"? or must i say anything since it's been modified?

I have attempted reading through the GNU documentation but it is not too obvious and I'd rather not break any rules

For modifications, you have to pay special focus on section "5. Offerring Modified Source Versions". Particularly, the notices you have to give are:

  • a) The job must carry prominent notices proclaiming that you modified it, and giving another date.

  • b) The job must carry prominent notices stating that it's launched under this License and then any conditions added under section 7. This requirement modifies the necessity in section 4 to “keep intact all notices”.

For how you can interpret that language for any specific work: browse the FSF's GPL FAQ, then talk to your legal consultant.

You need to keep your original author notice intact to change it. Check this out for more information.

Based on this: http://world wide web.gnu.org/licenses/gpl-3..html http://world wide web.gnu.org/licenses/gpl.html (because the striked you will most likely connect to more recent version later on)

(5. Offerring Modified Source Versions.)

You might convey a piece in line with the Program, or even the modifications to produce it in the Program, within the type of source code underneath the relation to section 4, so long as additionally you meet many of these conditions:

a) The job must carry prominent notices stating that you simply modified it, and giving a relevant date.

b) The job must carry prominent notices stating that it's launched under this License and then any conditions added under section 7. This requirement modifies the necessity in section 4 to “keep intact all notices”.

c) You have to license the entire work, in general, under this License to anybody who makes having a duplicate. This License will therefore apply, together with any relevant section 7 additional terms, to the entire work, and all sorts of its parts, no matter the way they are packed. This License gives no permission to license the job in a other way, but it doesn't invalidate such permission for those who have individually received it.

d) When the work has interactive user connects, each must display Appropriate Legal Notices however, when the Program has interactive connects that don't display Appropriate Legal Notices, your projects do not need to make sure they are achieve this.

A compilation of the covered use other separate and independent works, which aren't by their character extensions from the covered work, and which aren't coupled with it for example to create a bigger program, in or on the amount of a storage or distribution medium, is known as an “aggregate” if the compilation and it is resulting copyright aren't accustomed to limit the access or legal privileges from the compilation's customers beyond exactly what the individual works permit. Inclusion of a covered operate in an aggregate does not cause this License to use towards the other areas from the aggregate.

Obviously this isn't legal counsel

If you're not disbursing the program, you can usually benefit from what's known as the net services loophole. Unless of course the affero version of GPL can be used, you don't need to create any changes open to others than individuals who've the binaries from the software. Simply using the program over web doesn't count.

However, I believe you'll still have to mention the authors as always, but I'm not an attorney...