Options Clearing Corporation
In 2011, OCC was the largest clearing house in the USA. The Securities and Exchange Commission (SEC) and the Commodity Futures Trading Commission (CFTC) are the two parts of government that watch over OCC.  Under the SEC, OCC helps with stocks and options, indexes for stocks, foreign currencies, and futures contracts. The OCC is called a "registered Derivatives Clearing Organization (DCO)" by the CFTC.  The have helped pay for schools to teach investors about trading, and they help finance advisors and companies learn answers to very difficult problems. They also teach about risk.