While there aren't any software licenses that do that, many projects do it as a condition of accepting contributions. As an example here is GCC's contributor d

While there aren't any software licenses that do that, many projects do it as a condition of accepting contributions. As an example here is GCC's contributor documentation: https://gcc.gnu.org/contribute.html https://gcc.gnu.org/contribute.html The short version is assign FSF copyright, or put it in the public domain.