This legislation, known as the "Defining Dealer Act," aims to significantly revise the definition of a "dealer" within the Securities Exchange Act of 1934. It clarifies that a dealer is any person who engages in the business of effecting securities transactions for customers by both buying from them for their own account with a view to disposing of them elsewhere, and by selling to them securities purchased for their own account elsewhere. The revised definition specifically excludes certain security-based swaps from this scope, except for those involving non-eligible contract participants. Furthermore, the Act includes provisions for addressing past legal actions, requiring courts or the Securities and Exchange Commission to vacate orders or judgments that would not have been entered if the new definition of "dealer" had been in effect at the time.