I have plan to develop a new Forum Software based on "Phpbb". Phpbb as you know is released under GPL. My question is , Can i restrict people to modify the certain parts of my software (say footer.php contains link to my website and i don't want anyone to change it). Please reply as soon as possible.
Ya.. PHPnuke have the samething as you ask about.. Check their website for which license type they are talking about..
Even under the GPL, there are restrictions on how and when others can create derivative works. The GPL has never been fully tested in court, so all you can go on right now is the interpretation of the open source community itself. The way people will interpret it is that they CAN create derivative works based on your mods and distribute that work along with your code. However, it is NOT clear under the GPL that you actually have to SHARE your mods with anyone else. That portion of the GPL is the source of major dispute, and stands on extremely shaky legal ground.
There are plenty of LinuX distribution in the market. In the same can i develop a distribution of PHPBB and release it with a different name for example "XYZ". However i will mention that the Phpbb Group holds the copyright. I will launch this software just like a commercial one (cool preview, videos, theme songs....). I am damn sure that the release of my software will change the people's perception about open source. Besides i will also test my new business model in it. I try to develop a fair balance between freedom and commercial benifit in this model. Expected release date is september 15, 2006. Whatever my commercial aims are, its still free for all hunks and chicks.
Not true. There's no interpretation necessary; the license is quite clear. Also not true. As above, it's quite clear: if you distribute a modified version of GPL'd software, you have to share your changes. If you don't distribute it, you don't. This is irelevant in this case anyway, since the software concerned is written in PHP and therefore is always distributed as source code.
Wallace v. FSF is a single district court ruling binding nowhere but in this particular district. It was also dismissed without a finding on the merits at trial. Don't put much stock in it. The GPL is not a "license" or "contract" so much as a fork in the eye of companies and software developers that seek to profit from enhancing GPL software or creating derivative works. Outside of the core kernel architecture, the GPL has become an albatross around Linux's neck: a major impediment both to innovation and to sales for Linux developers. This is not to say that I am surprised. Richard Stallman, the GPL's architect made his intentions very clear in his GNU Manifesto. His utopian goal was to reject all commercial or proprietary modifications and eliminate money from software development. Stallman believed, and still does, that "this can give us a feeling of harmony which is impossible if we use software that is not free. For about half the programmers I talk to, this is an important happiness that money cannot replace." However, as with all purported Utopias, all is not well. Stallman's plans left software developers with several problems to face. The GPL spends as much time in political dialogue as it does in outlining the terms of the license. The GPL contains so few of the essential elements of a contract that no IP lawyer could say with a straight face (and without a call to check on his malpractice insurance) that the GPL would withstand scrutiny in court. Fundamental terms, including among others the inconsistent use of "based on" (derivative works), lack of a choice of law, and the ambiguous treatment of patents, make it unlikely that a court could give full effect to the GPL. That the Free Software Foundation has been able to get everyone--including notable names like Cisco and MySQL--to settle is a testament not to the GPL's viability in a court of law (as FSF claims), but to the costs associated with being the first company to fight the GPL (bad publicity, delays in product launch, possible product recalls, redundant development, lost profits, etc.) The GPL also is what we call a "viral" license, in that it forcibly propagates itself on any software developer who has incorporated GPL code into a project. Again, the prevention of proprietary modifications and limiting software's commercial appeal was Stallman's expressed goal. The viral nature of the GPL is a tool of Stallman's politics, not because viral propagation of the GPL license is necessary. Proprietary modifications to GPL code do NOTHING to prevent people from obtaining the original, unmodified code from its original authors or maintainers.
If you release the source, certainly not. If you don't release the source, you're into a legal gray area that (as you can tell from the discussion) is clearly unresolved at this point.
It seems like a lot of people complain about the GPL, because they can't take code and put it in a commercial application ... and they'll charge people money for other people's hard work. Make your own code and then all copyright is within your own hands. People choose to use the GPL license; no-one forces them to. We should respect their choice, just like you'd expect people to respect your commercial license and pay for the software. There is a lot of software out there using less restrictive licenses, because the software author chose that, so if you really want to use other's code then choose software by an author who doesn't mind copying his/her work. HINT: The really big money isn't in software itself but support contracts. But otherwise, you can still make money from a GPL product. So, you could release your product as GPL and charge for support no problem. You can make mods/add-ons/themes for your gpl software that carry a different license, too. Look at the other ways you can make money from this product.
And this is where you're missing the point. People DON'T get to choose to use the GPL. If I take a GPL program, the GPL adherents would say that anything I create that links to that code MUST ALSO BE GPL'ed. Even if I still give away your unmodified code in source form and distribute only my code under a commercial license, I would supposedly be violating the GPL. The GPL isn't about "respecting" choices--it is a viral license designed to DENY choice.