How can I ensure a portion of my project's code remains in all derivative works?

Question

I had an idea for a website. After much coding and thinking out the idea, I've got it to a decent stage.

If I were someone else, potentially a more commercially-minded person, I might want to sell it, or slather it with ads. However, I've fallen somewhat in love with open-source, and I'd like to host the project on GitHub and give it a nice open-source license.

However, the project seems to be getting better all the time and, in fact, I think that it'll quickly grow to be fairly popular. So I want to put ads on it that benefit charity.

How can I ensure that one small text advertisement benefiting charity remains in all derivative works? Are there any licenses that would let me do this?

p.s. My other requirement for a license is that it gives me attribution (in the same form as the MIT license would be fine)

[EDIT] I've decided to just let it be Apache licensed. I'm hoping that people will just leave charity-benefiting ads in.

Answer 1

I like Patkos' answer, but I'd like to throw in a few other things.

First off, I would assume you could modify the GPL, or another similar license, as they require attribution and you simply add the stipulation that the original advertisements must remain.

However, by doing this you are somewhat defying the concept of open source software, as the source is no longer (completely) open.

There is nothing preventing someone else from starting an open source project to duplicate your webapp, as long as they don't use your code. And given the choice, which do you think people will pick?

Personally, I believe you either have to embrace open source or not. Straddling the line will only alienate the public.

Answer 2

I think there is no prewritten license to fulfill your requirements. However, noone stops you write your own license and attach it to the original work.

On the other hand, if you have something successful and open-source you may want to consider a business model where users are not required to pay but may be encouraged to donate or support the project.

Open-source, by definition implies that the code is completely open, and no one person should be limited to modify it. GPL, MIT, CreativeCommons and other standard licenses guarantee attribution.

So, go open-source and be open, or make parts of the project closed source. You could make that module that contains the advertisement closed and make the rest of the project depend on it. This will, in some degree protect you, but may also be discouraging for developers to be required to depend on something secret from you.

Other business options would be to open only parts of your project and give them for free, but retain other parts of the project and keep the whole as a paid service.

Answer 3

If by "open source" you mean "Free Software", then you have no other choice but to allow every possible kind of commercial exploitation, except those that would prevent people from accessing the sources. If you put restrictions on the source, such as mandating the inclusion of certain advertisements, then the software is no longer "free" (as in speech).

So you want to make money off of the software: that's fine, nothing wrong with that. But I believe making in "open source, but not really" isn't the right way to do it: you will miss out on many of the benefits of Free Software (for example, your advertisement clause will make it impossible to include your software in, say, debian), but you won't see much of the benefits of proprietary software either.

Going proprietary is one way to go, and unless you are a full-scale bearded hippie, I don't see any problem with that - you will miss out on free contributions, you will have a harder time gaining traction in the market, and you will have to actively persuade people to buy your product rather than just throwing it out there and waiting for people to bite; but you will also be able to put whatever price tag you like on the software, and pepper it with as many ads as you like.

The other alternative is to go completely Open Source: pick a suitable pre-written Free Software license (there is no point writing your own: the existing ones already cover pretty much all needs), and release it. You can't make any money from selling licenses, and you can't include ads in the software either (that would be pointless, as any fork could just remove them), but here are a few things you can exploit for money:

• Support. As the author, you are the prime source of inside information on the software; it's OK to make people pay for that information.
• Custom extensions and modifications. More often than you think, people are more than willing to pay to see your software incorporate feature X, even if that means everyone else will also get the feature. They don't pay your for exclusive rights to your development effort, but for prioritizing features they need the most.
• Resume building. If it becomes popular, you'll be famous. Not rock star famous, but enough to give your professional networking a significant boost and increase your employability.

And then, there's dual licensing - in short, you can offer the product gratis under an Open Source license (typically one from the GPL family), and offer the option to "upgrade" to a commercial license that allows things your Open Source license doesn't (such as re-selling with modifications without providing sources). This is a thin line though, and it won't help your 'street credit' in Free Software land.

Answer 4

The only way you can protect yourself against this sort of thing is to a) have a license that protects you from this, b) catch someone doing it, and c) use the court systems for remedy. Are you prepared to do that? Let's say you craft the perfect extension to a license which fully protects you. Are you willing and able to fight that in court when someone violates it?

No matter how great your website software is, the chance of you making money off of it once it goes open source is very nearly 0%. Accept that, and realize that the benefit of giving your source code away reaps benefits far greater than a small amount of money. If your software is as great as you think it is, giving it away will help people and that's a good thing.