A bill entitled the "Taxpayer Antitrust Enforcement Act of 1983".

Amends the Clayton Act to authorize the Attorney General of the United States or of any State to bring suit on behalf of the United States or such State or a political subdivision or citizen thereof to secure monetary relief for injury sustained by reason of a violation of antitrust law, regardless of whether the United States, State, political subdivision, or citizen has purchased directly from the defendant.

Entitles the defendant in an antitrust action to prove as a partial or complete defense, in order to avoid duplicative liability, that some or all of the plaintiff's damages have been passed on to others who have standing to bring such an action.