On December 29, 2025, the Ninth Circuit upheld a district court’s refusal to grant Amazon’s request for a preliminary injunction to pause an ongoing unfair labor practice proceeding while Amazon litigates its constitutional challenge to the structure of the National Labor Relations Board (“NLRB” or “Board”).

The Ninth Circuit is the third federal appellate court to opine on how the Norris-LaGuardia Act (“NLGA”) limits the jurisdiction of federal courts to enjoin NLRB unfair labor practice proceedings while challenges to the constitutionality of Board job-removal protections are pending. The growing circuit split, which now involves the Third, Fifth, and Ninth Circuits, further signals that this issue is likely to be heard by the Supreme Court.

Background

In Amazon.com Services, LLC v. National Labor Relations Board, Amazon’s constitutional challenge originated in September 2024 after Region 31 of the NLRB issued a consolidated complaint on unfair labor practice charges targeting Amazon’s delivery service provider model.

The Acting Regional Director found merit to the allegations that Amazon and Battle Tested Strategies (“BTS”), a California-based delivery contractor, were joint employers, and by cancelling its contract shortly after BTS employees unionized with the International Brotherhood of Teamsters (“Teamsters”), Amazon effectively discharged drivers in violation of the NLRA. The consolidated complaint included additional unfair labor practices allegedly committed by Amazon as a joint employer of BTS employees, marking the first formal NLRB complaint against Amazon based on a theory of joint-employer status with one of its delivery contractors.

Shortly after Region 31 filed its consolidated complaint, Amazon sued the Board in the Central District of California to enjoin the unfair labor practice proceeding based on the theory that the NLRB’s structure and administrative procedures are unconstitutional because Board Members and administrative law judges are insulated from presidential removal.

On February 5, 2025, the district court denied Amazon’s motion for a preliminary injunction in part because the NLGA prohibits federal courts from issuing injunctions “in a case involving or growing out of a labor dispute.” The district court found that none of the NLGA’s narrow exceptions to this broad prohibition applied. On February 10, Amazon appealed to the Ninth Circuit.

The Ninth Circuit’s Decision

In its decision, the Ninth Circuit interpreted the NLGA’s text, which strips federal courts of their jurisdiction and power to issue injunctions “in a case involving or growing out of a labor dispute.”(emphasis supplied). On appeal, Amazon argued that the NLGA’s text imposes separate requirements as to what constitutes a case and what constitutes a labor dispute. Amazon further argued that its constitutional challenge—to which only Amazon and the NLRB are parties—fails to satisfy the case requirements because it is not an action between Amazon and its employees; it does not involve people engaged in the same industry, trade, craft, or occupation; and it is not related to terms and conditions of employment.

While the Ninth Circuit agreed that the NLGA imposes separate requirements to the pending case and the underlying dispute, it disagreed that Amazon’s constitutional challenge failed to meet the case requirements. Rather, the court held that Amazon’s challenge is a case within the meaning of the NLGA because (1) it was brought only after the NLRB issued a complaint on unfair labor practice charges, which would unquestionably qualify as a labor dispute; and (2) the parties have conflicting or competing interests in that underlying labor dispute. The Ninth Circuit specifically reasoned that the Teamsters need not be named as a party to the case for the case to qualify as a labor dispute under the NLGA.

A Growing Circuit Split

As the Ninth Circuit noted, Amazon’s argument adopted wholesale the reasoning of an August 2025 Fifth Circuit order affirming preliminary injunctions that paused unfair labor practice proceedings against SpaceX and two other companies while they litigated the constitutionality of the Board’s job-removal protections, as we reported here. The Ninth Circuit explicitly rejected the reasoning of the Fifth Circuit and noted that enjoining the underlying proceedings would improperly interfere with the Teamsters’ ability to vindicate the statutory rights of its members, which can only be accomplished through the NLRB.

Instead, the Ninth Circuit aligned itself with the reasoning of the Third Circuit, which, as reported here, rejected a similar request for injunctive relief in December 2025. The Third Circuit likewise rejected the reasoning of the Fifth Circuit and held that the NLGA broadly bars federal courts from issuing injunctive relief in disputes between employers and the NLRB.

Takeaways

With three federal appellate courts now weighing in on the NLGA’s jurisdictional limitations in the context of constitutional challenges to the Board and its administrative processes, an eventual date with the Supreme Court appears inevitable.

Employers should continue to monitor these and similar cases as they progress. If the Supreme Court endorses the Fifth Circuit’s reasoning, then that could potentially increase judicial intervention in labor disputes by authorizing federal courts to halt any NLRB proceeding where an employer subsequently raises a constitutional challenge. In contrast, should the Supreme Court adopt the approach of the Third and Ninth Circuits, then that would largely maintain the status quo on judicial intervention in labor disputes.

In addition, employers should also pay attention to the underlying complaint against Amazon, which will proceed following the Ninth Circuit’s order. With the NLRB recently regaining a quorum, as we covered here, the Amazon unfair labor practice proceeding would afford the Republican-majority Board the opportunity to weigh in on joint-employer issues.

We will continue to monitor these and other labor-related developments as they arise.