> Thanks. So, there is no way to obligate to liberate the code of these games
after a couple of years or something?
No. There is no law requiring anyone to publish source code to anything.
> how many years last their patents?
Video games are not typically patented. They are copyrighted. Copyright is
fundamentally different from patents.
Copyright monopolies in the U.S. last until 70 years after the death of the
author. In the case of anonymous works, pseudonymous works, and works made
for hire, the term is instead 95 years after publication or 120 years after
creation, whichever is shorter. So the effective answer is "forever". No work
which was created during your lifetime is a work you are ever going to see
enter the public domain. In fact, no work which was created during your
parents' lifetime is likely to be a work you are ever going to see enter the
public domain. And that's assuming the copyright industry doesn't purchase
yet another retroactive copyright term extension.