Ask HN: How do acquisitions work at FAANG?

I am curious how acquisitions work at FAANG or other BigCos.

Probably they have teams to find potential targets. Maybe not. What if a "normal" employee finds a good acquisition target? How do targets reach the right people at the company? Are those teams having a budget and buy what they want? Is there a limit? How it's decided if a C-level executive has to overlook the acqusition? Is there something special about acqui-hires? Are acqui-hired people being told in advance it is an acqui-hire or not?

I am not interested in legal stuff and due diligancs. There are dozens of topics about this but I couldn't find one talking about the internals of such acquisitions. It's just curiosity from me.