FAQ

What are the differences between the terms open source, sustainable software and developer source?

All these categories of software licenses allow end-users to access to the source code of the program, but there are some differences on when you can access to the source and what you can do with it.

- An open source license is usually so named when the license is compliant with the OSI standard (www.opensource.org).

- A sustainable software license gives you the right to access to the complete source code for free and to be able to redistribute it to a third party for research, test and development purposes. However there are some limitations on execution of the program or its derivatives (e.g. internal deployment use or commercial use) where you still have to pay a fee. In all the cases contributors can be rewarded for their work (under the form of a discounted license fee or from any other manner such as stock options in the company, percentage of the sales,...)

- A developer source license only gives you the right to access to the source code of the application when you have acquired a license (no free access), might restrict your rights or force the signature of a NDA.


Is Sustainable Software compliant with the Open Source Definition (OSD)?

No. Sustainable Software does not respect the Section 1 of the OSD which clearly mention that there should be no royalty at all on the program. Then sustainable software license restricts your freedom to freely use the program but neither restricts free access to the source code neither free possible redistribution of the program (always only for research and development purpose as there may be a charge for certain other type of execution).

For sustainable programs, a customer can still use the software without royalty but he HAS to involve himself in the community as an active contributor. Sustainable Software tries to incentive people to become new contributors at the place of just passively and freely using the software that others have developed.

Finally let's mention that the opposite is ture. An Open Source (FOSS) compliant software is de facto automatically also compliant with the Sustainable Software Definition which is indeed more permissive than the OSD. The only difference is based on the fact that FOSS authors have accepted to put a value of zero (gratis) to their programs or modifications.

Do I still need to pay a royalty to the original authors if I plan to use or resell a derivative work? 

Yes of course. Sustainable Software allows you to charge a fee on certain type of execution of the program. This is of course also valid for any of the derivative work. So even if you are only reusing part of the source code into another program, you will have to negotiate a commercial agreement with the original author. This is then similar to embedding a commercial program excepted that you always have the right to pay through additional contributions.

Of course, the author of a modification is also free to impose extra charges and conditions within the terms of the original program's license. To avoid discrimation on modified version (for example imposing high charges on modified versions), Sustainable Software Licenses may only discriminate according to the purpose of the execution of the software. So the conditions for the execution of a modified version of a package must be the same as for an unmodified version.

What is the Contribution in kind Agreement available in certain sustainable licenses?

The basic idea behind this attachment is that current open source licenses have no way to incentive value added contributors and to tax technology free-riders.

At the basis, we were discussing on the mechanism behind the Internet: everyone pays a small piece of connection and agree to transfer and carry someone else data. So you can pay only local calls even if you are in relation with another country. We wanted the same for our programs. Those that contributed to the development of the technology could use it for free or with substantial discounts, others were "taxed". We call that principle: the No Value Added Tax (NVAT) mechanism.

The main idea is to enforce a viral "pay or contribute" paradigm based on quid pro quo and on the principle that Time = Money. Either you become an active contributor to the project, either you accept to pay some cash royalties that will help finance other developers in the community. Every customer has the choice to pay his license fee in cash or in kind.

How does an editor value a contribution in kind? 

Most of the time a Sustainable Software stipulates that you can use the program without paying a license in cash or with substantial discounts if you agree to provide a Value Added Contribution to the project as a counterpart.

Usually the licenses do not mention explicitly how the contribution will be effectively valued as it may become quite complex to formalize. This task is let to the responsibility of the community or its technical committee.

Basically arguments such as:
- Complexity of the code developed
- Time needed to develop it
- Quality of contributions
- Involvement inside the community
are taken into consideration on a contributor per contributor basis to calculate the value of the license discount.

Can I reuse my contributions for other purposes?

Yes, similar to any other Open Source License, You reserve all rights, titles and interests in your contributions. You may then release your contributions under another license if you want to do so.

Where is going the money received from payment in cash?

Often there is still a lot of work to do that community developers do not like to do (such as GUI refactoring, configuration wizards, multi-platform installer, tests, documentation ;...). Then, money received from license sales will most of the cases pay maintenance tasks or modifications and new extensions of the software. Then, those that pay a cash royalty also contribute indirectly to the maintenance and the development of the program.