Now that we have learned about the common economic definitions of futures and other derivatives, it’s time to see how the relevant US laws and regulations define these financial instruments. The legal and regulatory definitions of derivatives and other financial instruments are often different from the common economic definitions of those selfsame instruments. Why is that? Contrary to what one might think, it is not because Congress wants to make life difficult for law students, or to confuse people. Instead, the differences between how various financial instruments are conceptualized in everyday life and how they are described in statutes and regulations are largely (although not solely) the result of Congress trying to make sure that people cannot easily evade applicable laws and regulations by simply creating look-alike financial instruments that would escape the regulatory framework that Congress had intended for such instruments. In many cases, the legal and regulatory definitions of financial instruments are more expansive and ambiguous than the definitions in common usage.