Berkshire Hathaway CEO Warren Buffett lost $1.4 billion on Tuesday after the world's largest bank by valuation, Wells Fargo, fell 3.3% after being penalised for opening 2 million fake accounts. Berkshire Hathaway, the bank's biggest shareholder, fell 2%, causing the world's fourth-richest person's fortune to drop. Notably, the world’s 400 biggest fortunes have lost $93 billion since Friday.