Here you will find in short an explanation of our licensing strategy.

Starting-points for Choice of Open Source License

Having decided to Open Source our products we were confronted with a very important decision to make: what Open Source license to use. We soon found that there appeared to be far more OSI approved licenses than we could imagine. We never got to choose an Open Source license for Sesame ourselves. Due to funding from the European Union and NLnet, we were restricted to using the GPL (General Public License). In a second Open Source project, named Aperture and started in 2005, we and DFKI ( Deutsche Forschungszentrum für Künstliche Intelligenz, or German Research Center for Artificial Intelligence) also wanted to use an Open Source license, but now we could choose ourselves. That was when we started looking at other Open Source licenses and tried to determine what we actually wanted to achieve with Open Source software. In discussions with others, checking Internet sites like the OSI site, reading books like the Cathedral and the Bazaar by Eric S. Raymond and Open Source licensing by Lawrence Rosen, our thoughts merged to:

• We strive to gain as many users of our Guided Exploration products as possible, improving computer use world-wide.
• We want to make our software available to others, to create a world-wide interest and community, to boost development.
• We want to use experience from others to develop our software and in return we want to allow others to use what we have made.
• We want to use a reciprocal license because we want improvements of our code to become available to the community.
• We do not want to enter into a technical discussion about Open Source licenses and we do not strive to enter into legal debates.
• We, as software developers, want to be able to understand the license ourselves.
• We are a (Dutch) company, that needs to generate income to keep up development.
• We have nothing against proprietary software.

Choice between OSL and GPL

This led us to compare the OSL (Open Source License) with the GPL (General Public License), asking a lawyer to compare the two for our situation. Some important conclusions in our lawyer's memo were:

• The OSL is written with the licensor as starting-point.
• The OSL is easy to read and understand (We realize that many users of our products are not large companies, with their own legal department, like us.)
• The OSL provides better protection of the rights of the licensor (concerning references to trade names and intellectual property, and automatic end of the license)
• The GPL, version 2 is dated and version 3 is not yet available, making the OSL more up-to-date.

Therefore we decided to make all our software products available under the OSL. We are convinced this is the best way to service our current and future customers and partners, meanwhile protecting our business interests as well.

Dual Licensing Model

Our choice to license our Open Source software under the OSL may discourage prospective licensees who are reluctant to accept certain conditions of the OSL. This may result in the situation where they cannot use our Guided Exploration software. To overcome the situation where our Open Source license restricts the use of our Guided Exploration software, we have decided to employ a dual licensing model, simultaneously making our software available under a commercial license.

Commercial License

For those prospective licensees who are reluctant to accept certain conditions of the OSL, like the reciprocity provision, we have decided to make our Guided Exploration software products available under a commercial license as well. The Aduna Commercial License relieves licencees from OSL conditions so that for example derivative works can be created that can remain proprietary. This way our developments can also be used in non Open Source projects, increasing the benefits of our Guided Exploration software for users. To compensate for the lack of attributions to the Open Source community, we have decided to ask a yearly fee that we can use to boost our development process. For information on licensing alternatives, we kindly ask you to contact Aduna sales.