I suspect jayvanguard is not talking about Berkshire Hathaway's public company investments (for which I'm sure Buffett does not use material non-public informat

I suspect jayvanguard is not talking about Berkshire Hathaway's public company investments (for which I'm sure Buffett does not use material non-public information) but Berkshire Hathaway's private company investments and acquisitions. These make up more than half the company's market cap, I believe.