1 Eigen is primarily MPL2 licensed. See COPYING.MPL2 and these links: 2 http://www.mozilla.org/MPL/2.0/ 3 http://www.mozilla.org/MPL/2.0/FAQ.html 4 5 Some files contain third-party code under BSD or LGPL licenses, whence the other 6 COPYING.* files here. 7 8 All the LGPL code is either LGPL 2.1-only, or LGPL 2.1-or-later. 9 For this reason, the COPYING.LGPL file contains the LGPL 2.1 text. 10 11 If you want to guarantee that the Eigen code that you are #including is licensed 12 under the MPL2 and possibly more permissive licenses (like BSD), #define this 13 preprocessor symbol: 14 EIGEN_MPL2_ONLY 15 For example, with most compilers, you could add this to your project CXXFLAGS: 16 -DEIGEN_MPL2_ONLY 17 This will cause a compilation error to be generated if you #include any code that is 18 LGPL licensed. 19
