Space X Stock - It's Turtles All the Way Down?

Elon Musk is worth about ten billion dollars. Much of that is tessel stock. The other part of it is space x stock. Space x is not a public company. There's no liquidity in space x stock. Elon certainly could sell some of his shares on the secondary market, but it's not easy or immediate. If he has a margin call on his loans, securitized loans from goldman and morgan stanley, and he needs liquidity to pay that off immediately, he's not going to be able to get that super quick from space x....