Warren Buffett's simple investment strategy has propelled Berkshire Hathaway to market-beating returns since 1965. Buffett has invested in over 100 different companies, including giants like Apple, Coca-Cola,

An exchange-traded fund keyed to Warren Buffett’s Berkshire Hathaway equity portfolio has attracted nearly $250 million since its inception in March. The VistaShares Target 15 Berkshire Select Income ETF holds 21 stocks—20 in Berkshire’s portfolio plus 10% of its assets in Berkshire’s Class B shares.

Perhaps that’s one reason stocks are selling off globally this morning. While most indexes in Asia and Europe remain near their all-time highs, there is broad-based but mild selling in all of them.