Simply you are mistaken, and that's not true (submitting the source code). First of all, lots of companies do license many 3rd party libraries, without their s

Simply you are mistaken, and that's not true (submitting the source code). First of all, lots of companies do license many 3rd party libraries, without their source code. Sometimes these said libraries are specifically compiled with latest bugfixes to the relevant project they've been used. What the companies might require is usually symbols/debug information/etc. But never the source code! After all, Microsoft, Sony, Nintendo are direct competitors. Why should an independent publisher (EA, Activision, THQ, Konami) be sharing source-code with them?