gplV2: can i use it for free or not?

Question

i'm confused, i've read the GPLV2 (and lesser GPL and all of them) over and over again, but i don't get it, and maybe you can:

i'm creating a website for a client. I get paid for that. When i'm done, the app won't be open source, it is solely meant to be used by my client.

Now i want to use a nice user control in it, but the control is licensed under GPLV2.

Can i use this control as a part of my app (i'm not selling the control, nor will i claim i've built it myself) or does me using this GPLV2 control mrean that the entire app must be relased as a GPLV2 ap too? (Which is NOT what i and the client want)

I'm very interested on your opinion.

This time i'm talking about the Telerik MVC controls on codeplex, but i once wondered the same thing for the CKEditor.

Answer 1

GPL license requires you to make the source code for you application available to anyone you distribute your application to. If you are hosting the application on your own server, you do not have to offer the code to anyone. But if your client runs it on their server, you would be obligated to offer them the code.

CKEditor is tri-licensed under the GPL, the LGPL, and the MPL, the LGPL and the MPL, if you use it under the LGPL or MPL license you are only obligated to release code changes you make to the CKEditor, but not your application.

If you don't want to pay for a license, and want to be safe, go with the CKEditor.

DISCLAIMER

I am not a lawyer, this is merely my interpretation.

Answer 2

Actually, there was some pretty good information in GPL sources include in commercial PHP web-service application as well concerning the use of licenses in web applications. The main thing is that the code, or a derivative of it, would need to be also licensed under the same licensing (from my interpretation of the license) link to GPLv2.

You definitely have to be careful about this type of issue due to the obvious legal consequences. What I have followed is to avoid it at all cost just to be on the safe side. However, realistically this is not the case in most instances. In one of our commercial applications we use jQuery. This is dual licensed, but to be on the safe side we put the libraries used for this under a separate directory (i.e. scripts/jquery). Then we made sure our product would function without the jQuery libraries. This gives us confidence that if there ever was an issue we can simply leave those files out of the package.