20 Licenses and Dependencies
Stan and its dependent libraries, are distributed under generous, freedom-respecting licenses approved by the Open Source Initiative.
In particular, the licenses for Stan and its dependent libraries have no ``copyleft’’ provisions requiring applications of Stan to be open source if they are redistributed.
This chapter specifies the licenses for the libraries on which Stan’s math library, language, and algorithms depend. The last tool mentioned, Google Test, is only used for testing and is not needed to run Stan.