Wait, what?! How can you have cycles in an ownership graph?

Ah, answering my own question, it seems to be called "circular ownership" and while it can sometimes occur from a long history of mergers and acquisitions (Samsung seems to be such a case), its generally a tax dodge or to mask ownership? At least, the top hits I see are all talking about it as a classic way to obscure oligarch ownership and things.

Genuinely curious who actually gets to make the decisions.

One important part of the answer is that there are two „Porsches“, a holding and a car manufacturer. It is also complicated though and there is much speculation who has how much influence.