Berkshire Filing Reveals Insurer Chubb as Buffett's Mystery Stock

Key Takeaways Warren Buffett's Berkshire Hathaway (BRK.A, BRK.B) has revealed that insurer Chubb (CB) is the mystery stock that the conglomerate had started building a position in last year but had asked regulators to keep under wraps. In its quarterly 13F filing with the Securities and Exchange Commission released late Wednesday, Berkshire said that it ended the first quarter with nearly 26 million shares of Chubb valued at about $6.72 billion. It's unclear why Berkshire had omitted Chubb from its filings ...