D. Xenakis wrote: > Can someone develop a closed source but NON-commercial software, by using > PyQT4 GPL license? no, by definition of GPL: if you are using a GPL library, you must distribute your software as GPL. (the GPL does not care about commercial / non commercial) http://www.gnu.org/licenses/gpl-faq.html#IfLibraryIsGPL -- ZeD