Warren Buffett teased to CNBC a ‘tiny purchase’ in March. Berkshire filing may have revealed it

Warren Buffett speaks with CNBC during the Berkshire Hathaway Annual Shareholders Meeting in Omaha, NE on May 2, 2026. David A. Grogan | CNBC Billionaire investor Warren Buffett hinted in March that Berkshire Hathaway had made a small addition to its portfolio. A new regulatory filing may have just revealed what he was referring to. …