SENTENSA software is 100% GPL (General Public License) and LGPL (Lesser General Public License); if your software is 100% GPL and LGPL compliant, then you have no obligation to pay us for SENTENSA licenses. This is a great opportunity for the open source community and those of you who are developing open source software.

The formal terms of the GPL and LGPL can be found at the site of the Free Software Foundation (GPL, LGPL). Please note that the GPL and LGPL can be restrictive, so if they don't meet your needs, you are better served by a SENTENSA Commercial License.

SENTENSA Knowledge Miner’s two major parts – Indexing and Search – are distributed under differing licenses: Indexing under LGPL and Search under GPL. The LGPL license is primarily used by SENTENSA in order to permit the user to link the SENTENSA Knowledge Miner’s Indexing library into non-free programs (this is not permitted under the GPL).

A product based on SENTENSA Knowledge Miner can use a standard commercial license that includes user restrictions to third parties. This is illustrated in the simplified model below:

Note that the GPL and LGPL do not restrict a user from charging a fee for the distribution of software. However, the distributed software must (unless the LGPL exception, as illustrated above, is applicable) be free for the user to use (i.e. freedom of redistribution, amendment of the software, etc).

• SENTENSA is free to use for those who are 100% GPL (for search) and 100% LGPL (for indexing) compliant. If your application is licensed under GPL/LGPL or compatible OSI license approved by SENTENSA, you are free to ship any GPL/LGPL SENTENSA software with your application ('application' means any type of software application, system, tool or utility). You do not need a separate signed agreement with SENTENSA, because the GPL/LGPL license is sufficient. We do, however, recommend you contact us, as there usually are good opportunities for partnership and co-marketing.
• Under the Open Source License, you must make the complete source code openly available for the application that is built on SENTENSA. You do not need to release the source code for components that are generally installed on the operating system on which your application runs, such as system header files or libraries.
• SENTENSA is free to use for those who never copy, modify or distribute it. As long as you never distribute (internally or externally) the SENTENSA software in any way, you are free to use it for powering your application, irrespective of whether your application is under GPL/LGPL or not.
• You are allowed to modify SENTENSA software source code any way you like as long as the distributed derivative work is licensed under the GPL/LGPL as well.
• You are allowed to copy SENTENSA binaries and source code, but when you do so, the copies will fall under the GPL/LGPL license.

1. Non-Profits, Academic Institutions, and Private Individuals

If you represent a non-profit organization or an academic institution, we recommend you publish your application as an open source / free software project using GPL/LGPL. Thereby, you are free to use SENTENSA software free of charge under GPL/LGPL. We believe that if you have strong reasons to not publish your application in accordance with the GPL/LGPL, you should purchase commercial licenses.

Please note that even if you ship a free demo version of your own application, the above rules apply.

2. Recommendations

Please note that SENTENSA can only give advice on which license is right for you. The final judgment, of course can be made only by a court of law. Having that said, we recommend purchase of the commercial license to all commercial and government organizations. This frees you from the strict requirements of the GPL/LGPL license.

To all free software enthusiasts we recommend our products under the GPL/LGPL license. To anyone in doubt, we recommend the commercial license. It is never wrong.

3. Support

Users of the SENTENSA software can benefit from our different support packages. SENTENSA Support is designed to save you time and to ensure proper functioning of your SENTENSA products at all times. Whatever you need, we have a support level to match your requirements. For more information please refer to the support page.