The oracle of omaha is the insurance king. Cash flow is predictable and the odds are in your favor. It’s like being the house in Vegas, you take some hits but in the long run it’s a cash flow machine.
Regarding Gieco and General Re, they are wholly owned subsidiaries of Berkshire Hataway and they don’t have to raise funds in part because their parent company has $27 billion in cash. (nice checking account balance! :-)) They are stock insurance companies with Berkshire owning 100% of the stock. And Berkshire is public so they are not “private” companies. They have all the same reporting requirements as any other subsidiaries and they are included in Berkshire’s annual report.