Wow. I would never have expected that in other countries what you produce on your own time is the property of your employer. That is an absolute non-starter for entrepreneurship .
It's not 'other countries', or exactly what you're saying. It's that other locals (including other states) don't explicitly state otherwise in law.
In many states it's either not mentioned, or left to your employment contract details - in California, it's enshrined in the legal code.
