The Securities and Exchange Commission takes the lead in defining what a security is, not necessarily legislation, the regulator's Chair Gary Gensler said. 

“If Congress were to act, though I don’t think we need these authorities, not to undermine inadvertently through definitions of what’s in or out, or in essence allowing for conflicts that we don’t allow,” Gensler said. 

“I think many of the legislative vehicles would, if adopted, would undermine the securities remit,” Gensler added.