I am not a lawyer. If you want legal advice, talk with a lawyer. Here is the license for the C# compiler (Roslyn): https://github.com/dotnet/roslyn/blob/maste

I am not a lawyer. If you want legal advice, talk with a lawyer. Here is the license for the C# compiler (Roslyn): https://github.com/dotnet/roslyn/blob/master/License.txt https://github.com/dotnet/roslyn/blob/master/License.txt The license is an MIT which means that you should be able to fork the language and do anything you want with it. The names "C#" and ".NET" are Microsoft trademarks and so you would need to use some other name