A lawsuit claiming Amazon is prohibiting vendors from offering their products at reduced prices on other websites hangs over the company's head as it enters Prime Day, one of its biggest sales occasions of the year.

The Federal Trade Commission's long-awaited antitrust complaint is the organization's most assertive effort to date to restrain Amazon's market dominance, a business that has come to be associated with online shopping and quick deliveries.

To rectify what many of her supporters perceive to be decades of lax antitrust enforcement, the agency hasn't been afraid to test the boundaries of competition law and take strong measures against some of America's largest corporations.

The FTC's attempt to stop Microsoft's acquisition of Activision Blizzard and Meta's acquisition of the virtual reality firm Within Unlimited are two high-profile examples of how this strategy backfired.

Khan has come full circle with the Amazon case, which was supported by 17 states. She is now directly fighting the organization she analyzed in a significant academic article she wrote while a Yale Law student. Khan stated in a paper titled "Amazon's Antitrust Paradox" that the traditional method of evaluating anti-competitive behavior by its effect on prices was inadequate in the modern economy. She advocated for a more modern strategy that considers how business concentration affects the larger market.

President Joe Biden, whose administration has adopted a harsher line on antitrust enforcement, chose Khan to lead the FTC two years ago.

Her agency is now expected to demonstrate in court that Amazon is a monopoly and that it is abusing its power to stifle market competition.

If the lawsuit is not dropped by a new administration, dismissed by a judge, or results in a settlement like the one Amazon negotiated with European regulators last year, a final decision in the Amazon case will probably not be made for years.

Trial in a related action brought by the state of California last year is scheduled for 2026. A federal judge dismissed the District of Columbia's lawsuit against Amazon last year after it attempted to sue the online retailer on antitrust grounds in the past.