The Sherman Antitrust Act specifically provides in section six that property may be forfeited if owned under an agreement in violation of the provisions of the Act. The scope of what may be forfeited as a result of anticompetitive conduct ranges from real assets like land and machinery to pecuniary interests such as income derived from a monopolistic operation. The provision states that any property that is owned under any prohibited contract or by any unlawful combination is subject to forfeiture. It goes on to include property that is subject to a conspiracy. For example, a milk producer who conspires with a competitor to share resources and create barriers to entry to their market might face a forfeiture of income derived from artificially high-priced milk, or even forfeiture of his entire bottling operation. The forfeiture statute gives prosecutors a powerful weapon in investigating and prosecuting antitrust cases, since it enables them to freeze a suspect’s bank account in order to get a snapshot of their operation. It has the further effect of immobilizing a defendant, quite literally, as defense funds and travel expenses are hard to come by with a frozen account.

The forfeiture statute expressly references section one of the Sherman Act, which refers to the specific contracts, combinations, and conspiracies to unreasonably restrain market competition. Thus, all per se violations (such as price fixing and bid rigging) are subject to property forfeiture. Property owned under a collusive contract or subject to such a conspiracy is forfeited to the United States. The proceedings for seizing and condemning such property is identical to the proceedings for property that is imported into the United States contrary to law.