By definition, a license that discriminates against commercial use would not be open source, if I understand correctly (http://www.opensource.org/docs/osd http:

By definition, a license that discriminates against commercial use would not be open source, if I understand correctly (http://www.opensource.org/docs/osd http://www.opensource.org/docs/osd). That said, the GPLv3 would probably meet your needs well. It ensures that if anyone modifies your program and distributes it, they are obligated to release their changes to the source code (also under the GPL). I suppose they could still bundle your code up and sell it, but at least any value added by them in terms of program-modification should come back to you.