Selling software that includes 3rd party open source

[Limited]

We have developed some software that we would like to sell. We've got a bit of interest from existing customers, and I'm trying to put together the licence side of things. I've just realised that we're using a number of open source dlls and just wondered if anyone knows what the situation is with these. I'm guessing that doesn't stop us selling the software - do we just need to reference them in someway, include their licence details etc. Do the rules vary depending on the authors.
I've read the GNU but it doesn't make much sense to me.

Anyone done anything similar?

thanks

[DaveB]

We have developed some software that we would like to sell. We've got a bit of interest from existing customers, and I'm trying to put together the licence side of things. I've just realised that we're using a number of open source dlls and just wondered if anyone knows what the situation is with these. I'm guessing that doesn't stop us selling the software - do we just need to reference them in someway, include their licence details etc. Do the rules vary depending on the authors.
I've read the GNU but it doesn't make much sense to me.

Anyone done anything similar?

thanks

IANAL

As I understand it the GPL essentially means that if you incorporate any Open Source software licenced under the GPL in your own software you must :

A) Make the source code available for those parts covered by the GPL

B) Include full credit to the original authors of the GPL parts.

C) Allow free redistribution of the GPL items by anyone you sell the software to.

D) If any part of your application contains GPL code in such a way that it cannot be readily identified as a seperate component in it's own right, then the entire application must be distributed under the GPL, free of charge.

[RichardCranium]

You need to check the licence for each piece of open source software (assuming it is open source and not shareware or similar) you have used; there are many different types of licence.

If the GNU licence is the one that applies, there are varying forms of that too.

But I cannot help wonder, if you cannot interpret a very popular software licence, should you be selling licensed software without using proper legal advice?

[VectraMan]

If it's libraries, then they're often LGPL (or something similar), which basically means you can do what you want and include it in your application (and charge money). But you should check the terms carefully. I've used a couple of libraries like this recently, and all they say is that you have to acknowledge it somewhere and not try to pretend it's your work.

As I understand it, GPL means you essentially can't link it as part of your application, unless you also release your application under the GPL. However I have used GPL software within commercial applications that's launched as an external tool. I.e. My software runs and passes parameters to another bit of software that happens to be GPL and just happens to be included in my distribution.

[blacjac]

If it's libraries, then they're often LGPL (or something similar), which basically means you can do what you want and include it in your application (and charge money). But you should check the terms carefully. I've used a couple of libraries like this recently, and all they say is that you have to acknowledge it somewhere and not try to pretend it's your work.

As I understand it, GPL means you essentially can't link it as part of your application, unless you also release your application under the GPL. However I have used GPL software within commercial applications that's launched as an external tool. I.e. My software runs and passes parameters to another bit of software that happens to be GPL and just happens to be included in my distribution.

Stands for lesser gnu public licence.

Basically, GPL = your software should be free, LGPL = you can charge for it.

Make sure all software you use is LGPL, but if you have to use GPL software, as others have said, make it a stand alone module that you give away free with your main product that you charge for (if that makes sense).

[Limited]

All very helpful

Thanks

[TheCyclingProgrammer]

Stands for lesser gnu public licence.

Basically, GPL = your software should be free, LGPL = you can charge for it.

Make sure all software you use is LGPL, but if you have to use GPL software, as others have said, make it a stand alone module that you give away free with your main product that you charge for (if that makes sense).

A minor point, but there is nothing in the GPL stopping you from selling your software as long as you comply with the terms of the license (which as others have pointed out, basically involves releasing any code that links to the GPL'd code under the GPL license).

I'm not a big fan of the GPL's viral nature to be honest and prefer to release all of my own open-source code under a permissive license such as the MIT or BSD.

[blacjac]

A minor point, but there is nothing in the GPL stopping you from selling your software as long as you comply with the terms of the license (which as others have pointed out, basically involves releasing any code that links to the GPL'd code under the GPL license).

I'm not a big fan of the GPL's viral nature to be honest and prefer to release all of my own open-source code under a permissive license such as the MIT or BSD.

Absolutely correct, you don't have to 'give it away', but when you do sell it you have to provide the source code with it in order to comply with the GPL.

So the difference between LGPL and GPL is that with GPL you have to provide the source code and the customer has the right to modify it as they see fit, then pass it on (or sell it). With the LGPL they don't.

When the GNU community use the word 'free', they don't mean no cost, but once you have obtained the software you are then free to do what you want with it.

[BlasterBates]

You can sell your own source code. There's nothing to stop you including the Open Source on your distribution, but you can't copyright it. The GNU license is just there to stop you copyrighting the Open Source.

[TheCyclingProgrammer]

You can sell your own source code. There's nothing to stop you including the Open Source on your distribution, but you can't copyright it. The GNU license is just there to stop you copyrighting the Open Source.

As above, its a bit more complicated than that. Linking to GPL'd code means you need to release your own code under the GPL (although you can still sell it). It's not really a matter of copyright.

That said, I don't remember any of this GPL stuff being tested in court.