Not a bad idea honestly. Would be interesting to see how it affects tech companies since they rely on hypergrowth. My one worry is that instead of divesting they would just play shell games with complex ownership structures.
Berkshire Hathaway: it's a holding company, spin out the big holdings
Nvidia (this one is tougher): Ethernet, Video Cards, AI cards; maybe chipsets vs cards?
Meta: Facebook, Instagram, WhatsApp. Or ... split out the internal Cloud Services from the frontends.
TSMC: I dunno what to do here, but it's also not a US corp, so yeah. You could spin off fabs by node maybe.
United Health: not a tech company, but Insurance (possibly spin out regionally), Regional Healthcare Providers, Pharmacy Stuff
There's potential to break up some of the other companies along regional lines, like the Baby Bells ... but IMHO, that doesn't make that much sense for most of these.
Have some sort of phase-in, but if ownership between formerly related companies remains similar, contracts between them need to be a) public, b) terms must be available to others (FRAND). For cases where the spun-off companies are still market dominant (a lot of what I've suggested), constrain the company from entering other markets; this doesn't end the monopoly, but it prevents using one dominant position to establish another.
Not OP but a progressive tax generally scales non-linearly to tax higher brackets a higher %. So then you have an increasingly lower / decreasing incentive to make even more money.
Many countries already have a progressive tax on income, but that is irrelevant to business profits.
Yep, exactly. There's an easy way to make it gradual, too: put the "heel" of the progressive tax above where the largest American companies are and let inflation bring them into the curve. They can either pay a tax cost not to split, or they can split.
Alternatively, don't. I expect this proposal to be popular with executives regardless because it creates new spots for executives, just as it does with lower-flying labor.
