China's stock market rout threatens $13 billion worth of snowball derivatives, putting pressure on brokerages to liquidate hedge positions and raising market volatility. About $4.2 billion of structured products tied to the CSI 1000 Index are near levels that trigger losses at maturity. In addition, $27 billion worth of derivatives, including autocallables, are at risk. Regulators have tightened their grip on these products to prevent them from being marketed to retail investors as fixed-income products.