Very good list, I have seen most in action. I would also add AI where some people just make their own internal tools rather than making it open source to everyone.

> Apple is the classic example of an employer that simply doesn’t let most staff do outside open source

I have been encountering this a lot recently, and I don’t know why. Last one a couple months ago, a company wanted to hire me for some work and while all verbal promises were good, when the contract was sent, it has some shady terms but workable nonetheless, except one, the company prevent you from working in any open source work, including personal ones without a written permission, and everything you do will be the company property on or off duty! Obviously I challenged that and they got offended to even dare to challenge it, no deal! Other companies too but that was the craziest one so far.

I work on a ton of different stuff, and this clause comes up for every job. I get them to remove it, or I don't accept the job offer.

For me, this is a red/green flag on management. The clause is legal boilerplate, inserted because it's standard and they can. They don't actually care that much about anything you might build outside of work. If they won't (or can't) remove it then the organisation is inflexible and the people who are hiring me have no power within it. Or the people who are hiring me don't understand my point of view. This is a bad sign either way.

I have had one "win" with it; I worked for a company run by a trio of absolute arseholes. One of them called a meeting and tried to bully me into handing over one of my projects because of this clause. I explained that my contract didn't have that clause because they removed it before I signed it. He got angry. But couldn't actually do anything about it.