and free software, and by critical governmental organizations (which are also working in domains like military and defense systems) also gives much more security than using the GPL alone, as the license is supported officially by a government which is a full member of WIPO, and by an enforceable law. This also means that all international treaties related to the protection of intellectual rights do apply to CeCILL-licensed products, and so they are enforceable by law in all countries that signed any of the international treaties protected by WIPO. However, this also leaves open the possibility that the French government will make a future version of the CeCILL unfree and restricted. The CeCILL license is approved as a "Free Software" license by the FSF with which the CeCILL project founders have worked. Since version 2.1, CeCILL is also approved by the Open Source Initiative as an "Open Source" license. Other CeCILL licenses The CeCILL project also adds two other licenses: CeCILL-B, which is fully compatible with BSD-like licenses (BSD, X11, MIT) which have a strong attribution requirement (which goes much further than a simple copyright notice), a requirement normally not allowed by the GPL itself (which describes it as an advertising requirement), and so this license may be incompatible with the original CeCILL license, if BSD-like components are integrated, unless the software uses a dual-licensing scheme and conforms to the licensing terms of all embedded components. CeCILL-C, for "component" software, which is fully compatible with the FSF's LGPL license. These two licenses are also defined to make BSD-like and FSF's LGPL licenses enforceable internationally under WIPO rules. Notable users Brian (software) G'MIC MedinTux Paradiseo PhoX Scilab ScientificPython SYNTAX Yass (software) Origins and general applicability Although the three CeCILL licenses were developed and used for strategic French research systems (in the domain of defense, space launching systems, medical research, meteorology/climatology, and various domains of fundamental or applied physics), they are made to be usable also by the general public or any other commercial or non-profit organization, including from other governments, simply because these software component need and use (or are integrated with) component software or systems which were initially released with an open-source or free license, and they are operated by organizations that also have a commercial status. Without these licenses, such systems could not have been built and used, and protected legally against various international patent claims. Due to the