This is fascinating, although I still feel there's too much disagreement for me to have a clear picture of how this works in California. I'll give a Dutch pers

This is fascinating, although I still feel there's too much disagreement for me to have a clear picture of how this works in California. I'll give a Dutch perspective (which perhaps applies to some degree to other parts of Europe): Until 2016, clients had to proactively ask for a 'Verklaring Arbeidsrelatie (VAR)'. An 'explanation of the work relationship'. If I understand correctly, the contractor/freelancer had to prove that they had more clients than just that one, and it had to be reasonable. So no having five clients of which one accounted for 99% of all income. If a client didn't ask for this 'VAR', it could cause problems down the road. From 2016 on they changed this, but apparently the result has been a confusing mess, so in 2021 they'll try to clear up some of it. Practically speaking, as a contractor, I've found that only the big clients (with legal teams, I imagine) would ask for a VAR, if at all. Most of the time, whether working in Holland or Germany, I usually did the exact same work that their employees did. In some cases there seemed to be vague distinction where I worked on shorter projects and they did support and the like, but in practice that distinction was very blurry. I suppose with some of these clients I could've caused trouble, but because I got paid well, often better than the full-timers (even with insurance and all that deducted), I didn't see any reason to. My general impression is that NL is a bit more 'liberal' in these matters than many other parts of Europe, so I'd be curious to hear how this works in France/Germany/Italy, etc.