Zoom out. Even after Friday's drop, Nu has soared 69% this year. Go back further, and you'll see the stock has soared 245% since the start of last year. Buffett owns 20.7 million fewer shares now, but the value of his Nu stake is 56% higher than it was at start of this year and a beefy 197% greater than it was a year earlier.

Warren Buffett is stockpiling cash. His Berkshire Hathaway holding company continued to sell more than it bought in the third quarter when it offloaded a quarter of its stake in Apple, regulatory filings revealed Thursday.