Antitrust enforcement has long represented a significant source of corporate liability exposure, and, as D&O Diary readers know, often serves as the catalyst for follow-on securities class actions and derivative suits. In the latest example of this litigation pattern, online real estate and rental marketplace, the Zillow Group (“Zillow”), and its CEO and CFO, have been named as defendants in a securities suit after the FTC filed an antitrust lawsuit against Zillow in September.
The June 9, 2026, complaint against Zillow can be found here (Zillow SCA).
Background
According to the Zillow SCA, in February 2025, Zillow and Redfin, a residential real estate brokerage platform, entered into an agreement under which Zillow became the exclusive provider of multifamily rental listings on Redfin’s platform and affiliated websites. Zillow publicly described the arrangement as a partnership designed to expand listing distribution and increase exposure for rental properties.
According to the FTC, however, the arrangement was something quite different. In a complaint filed on September 30, 2025, the agency alleged that Zillow paid Redfin $100 million to exit the multifamily rental advertising market and transfer its business to Zillow. The FTC alleged that Redfin agreed to stop competing for multifamily rental advertising, terminate existing contracts, transition customers to Zillow, transfer competitively sensitive information, and facilitate the hiring of employees associated with the business. According to the FTC, the arrangement effectively eliminated Redfin as an independent competitor in the relevant market.
The FTC characterized the agreement as “an end run around competition” and alleged that it violated Section 1 of the Sherman Act and, viewed as an acquisition, Section 7 of the Clayton Act. The agency contended that Zillow had effectively paid a competitor to stop competing. Shortly after the FTC’s filing, five states (New York, Virginia, Arizona, Washington, and Connecticut) jointly sued Zillow and Redfin over the same $100 million rental listing market arrangement. On May 6, 2026, a federal judge denied Zillow’s motion to dismiss the FTC complaint.
The Zillow SCA
The core allegation is that Zillow mischaracterized the Redfin transaction as a “partnership” when it allegedly functioned as an acquisition of Redfin’s multifamily rental advertising business. The complaint alleges that defendants failed to disclose that the arrangement materially increased the company’s exposure to antitrust scrutiny and enforcement risk.
According to the complaint, investors were misled regarding both the nature of the transaction and the extent of the regulatory risks associated with it. The plaintiffs further allege that, even after the FTC filed suit, Zillow continued to downplay its legal exposure and the potential consequences of the antitrust allegations.
The complaint alleges violations of Sections 10(b) and 20(a) of the Securities Exchange Act and seeks damages on behalf of investors who allegedly suffered losses following the various disclosures relating to the FTC’s enforcement action and the associated litigation costs.
Discussion
The Zillow SCA represents the latest example of a well-established litigation phenomenon in which antitrust enforcement actions spawn follow-on securities litigation. As D&O Diary readers know, whenever a company becomes the subject of a significant antitrust investigation or enforcement proceeding, there is often a corresponding effort by shareholders to contend that investors were not adequately informed about the company’s regulatory risks, compliance deficiencies, or allegedly anticompetitive business practices.
The theory underlying the Zillow SCA follows this familiar pattern. The plaintiffs do not seek to establish that Zillow violated the antitrust laws. That issue will be determined in the underlying FTC action. Rather, the securities plaintiffs contend that the company mischaracterized the nature of the Redfin transaction and failed adequately to disclose the extent of the antitrust risks associated with the arrangement. In that respect, the case is less about antitrust law than it is about disclosure obligations.
The lawsuit is also noteworthy because it arises at a time when antitrust enforcement is expanding beyond traditional price-fixing and cartel cases. We have been following how antitrust theories increasingly are being applied in a variety of contexts, including ESG-related stewardship activities, labor market restrictions, college athletics, and industry governance structures. The FTC’s challenge to the Zillow-Redfin arrangement likewise reflects a broader willingness by regulators to scrutinize strategic partnerships, information-sharing arrangements, and other commercial agreements that allegedly reduce competition without taking the form of a conventional merger.
From a D&O perspective, one of the most significant aspects of this trend is that antitrust investigations frequently create multiple layers of potential liability. A company facing antitrust scrutiny may confront not only regulatory proceedings and private antitrust litigation, but also securities class actions, derivative suits, and books-and-records demands. The resulting defense costs and settlement exposure can substantially exceed the consequences of the underlying antitrust proceeding itself.
The case also highlights an issue that frequently arises in the D&O insurance context. Antitrust claims brought directly against a corporate entity often do not fall within the definition of a covered “Securities Claim” under a public company D&O policy. Yet when shareholders file a follow-on securities class action based on the same underlying conduct, the securities suit itself typically does trigger entity coverage under the D&O program. The result is that an antitrust investigation that may not itself be covered can nevertheless generate a covered securities claim with significant defense and indemnity exposure.
Whether the Zillow securities suit ultimately survives a motion to dismiss remains to be seen. The plaintiffs will still have to establish that the challenged statements were materially misleading and that the defendants acted with the requisite scienter. Nevertheless, the filing is a reminder that antitrust enforcement actions often have consequences extending well beyond the regulatory proceeding itself. As regulators continue to pursue increasingly expansive antitrust theories, companies and their boards face a growing risk that antitrust scrutiny will be followed by shareholder litigation seeking to convert competition-law allegations into securities law claims.