Maybe what I am asking is ambiguous. However, @dogma said that anything you work on during the time you are employed might be regarded as company IP.
What I am asking is what happens with work/projects/apps that someone has done on the side before joining a company, and especially in the case that this creates a revenue stream.
Oh in that case I'm not sure, but I would always be clear with the employer at the interview stage.
In my current role I mentioned that I work on things on the side and they were like... oh that's not allowed, and I said... oh well I can't work here then.
In my current role I mentioned that I work on things on the side and they were like... oh that's not allowed, and I said... oh well I can't work here then.
Good for you! There seems to be a certain mindset in some company bosses, and it's usually middle management types who have made it to a moderately senior level and never not been "company men" (or women etc. obviously) in my experience. It's like they think becoming an employee at their firm means giving over your life to them, and that by graciously allowing you to work for them they're doing you some big favour that justifies that stance. This is supported by the corporate lawyers routinely trying to insert heavily one-sided terms into employment contracts. But that simply isn't what an employment relationship is, certainly not in the West in 2020, and enough good people saying "no" and being willing to walk away is the only way the "we own you" people will learn.
What I am asking is what happens with work/projects/apps that someone has done on the side before joining a company, and especially in the case that this creates a revenue stream.