1*bf2c3715SXin LiEigen is primarily MPL2 licensed. See COPYING.MPL2 and these links: 2*bf2c3715SXin Li http://www.mozilla.org/MPL/2.0/ 3*bf2c3715SXin Li http://www.mozilla.org/MPL/2.0/FAQ.html 4*bf2c3715SXin Li 5*bf2c3715SXin LiSome files contain third-party code under BSD or LGPL licenses, whence the other 6*bf2c3715SXin LiCOPYING.* files here. 7*bf2c3715SXin Li 8*bf2c3715SXin LiAll the LGPL code is either LGPL 2.1-only, or LGPL 2.1-or-later. 9*bf2c3715SXin LiFor this reason, the COPYING.LGPL file contains the LGPL 2.1 text. 10*bf2c3715SXin Li 11*bf2c3715SXin LiIf you want to guarantee that the Eigen code that you are #including is licensed 12*bf2c3715SXin Liunder the MPL2 and possibly more permissive licenses (like BSD), #define this 13*bf2c3715SXin Lipreprocessor symbol: 14*bf2c3715SXin Li EIGEN_MPL2_ONLY 15*bf2c3715SXin LiFor example, with most compilers, you could add this to your project CXXFLAGS: 16*bf2c3715SXin Li -DEIGEN_MPL2_ONLY 17*bf2c3715SXin LiThis will cause a compilation error to be generated if you #include any code that is 18*bf2c3715SXin LiLGPL licensed. 19