Buybacks can continue for as long as Berkshire has at least $30 billion in cash and equivalents on its balance sheet. Since the conglomerate is sitting on a staggering $347 billion in liquidity right now, Buffett and his team can authorize more buybacks whenever they feel the time (or the price) is right.

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.