Labor & Employment Law Daily Wrap Up, LABOR—UNFAIR LABOR PRACTICES—9th Cir.: NLRB erred in finding work-preservation defense unavailable in pure jurisdictional disputes, (Jun 20, 2025)

By Todd Harrison, J.D.

The Board’s position was foreclosed by a prior Ninth Circuit decision that found a valid work-preservation objective provides a complete defense against alleged violations of NLRA Sections 8(b)(4)(D) and 10(k).

Vacating an NLRB order directing the ILWU to cease and desist from pursuing maintenance work for SSA Terminals at the Port of Seattle, the Ninth Circuit found the Board erred when it determined that the work-preservation defense was not available in pure jurisdictional disputes, like this one, where multiple unions have valid contractual entitlements to the disputed work directly with the employer. The court held that the Board’s position was foreclosed by International Longshore and Warehouse Union v. NLRB (Kinder Morgan). Accordingly, the court vacated the Board’s order and remanded for the Board to evaluate the merits of the defense in the first instance (International Longshore and Warehouse Union v. NLRB, No. 23-632 (9th Cir. Jun. 18, 2025 vacated Dec. 16, 2025)).

Jurisdictional dispute. When multiple unions have irreconcilable contractual rights to perform the same work for the same employer, the resulting disputes are referred to as “jurisdictional disputes.” Here, a jurisdictional dispute arose between the International Longshore and Warehouse Union (ILWU) and the International Association of Machinists and Aerospace Workers (IAM), both of which claimed the right under collective bargaining agreements to perform certain work for SSA Terminals.

Conflict. In 2018, SSA Terminals began operating Terminal 5 of the Port of Seattle as a marine terminal, making Terminal 5 subject to Section 1.72 of a master collective bargaining agreement, the Pacific Coast Longshore Contract Document (PCLCD). However, this posed a conflict. Section 1.72 required SSA to assign the maintenance work to ILWU, but it also had a separate bilateral agreement with IAM, guaranteeing IAM-represented mechanics the right to perform all maintenance work at Terminal 5.

Initially, SSA assigned the maintenance work to ILWU. In response, IAM threatened “economic action” at Terminal 5.

Two-step mechanism. A two-step mechanism is employed when the Board is faced with a jurisdictional dispute. First, NLRA Section 8(b)(4)(D) makes it an unfair labor practice to “threaten, coerce, or restrain” an employer with the object of forcing that employer to “assign particular work to employees in a particular labor organization... rather than to employees in another labor organization.” Second, when the Board finds cause to believe that section 8(b)(4)(D) has been violated, Section 10(k) empowers it to hold a hearing and to award the disputed work to one of the competing unions.

SSA employed this mechanism here. First, it filed an unfair labor practice charge against IAM, alleging that its threat of “economic action” violated Section 8(b)(4)(D). This triggered Section 10(k), leading the Board to hold a hearing wherein it assigned the work to IAM.

Grievance. Refusing to accept the Board’s decision, ILWU pursued a grievance under the PCLCD seeking the value of the work assigned to IAM. An arbitrator found in favor of ILWU. From SSA’s perspective, the arbitration award made the Board’s Section 10(k) determination null and void.

Another unfair labor practice. SSA filed another unfair labor practice charge, alleging that ILWU had violated Section 8(b)(4)(D) because pursuing the grievance was intended to coerce SSA into assigning the work to mechanics represented by ILWU rather than IAM.

During a hearing before an ALJ, ILWU did not dispute that pursuing a grievance in defiance of a Section 10(k) award can violate Section 8(b)(4)(D). Rather, it argued that its conduct was immunized by the work-preservation affirmative defense. Specifically, it argued that pursuing the grievance was a “primary” union activity because it sought to accomplish a goal within the confines of its relationship with SSA.

The ALJ rejected this defense and the Board affirmed, holding that the work-preservation defense was unavailable in pure jurisdictional disputes, explaining that permitting a union to raise that defense would subvert Congress’s intention to “afford employers protection when their actions conform to a Board determination under section 10(k).” ILWU was ordered to cease and desist from pursuing the work at Terminal 5. This appeal followed.

Undisputed. Several issues were undisputed by the parties. They agreed that this was a genuine jurisdictional dispute and that when both unions pursued the maintenance work it was appropriate for the Board to resolve the dispute under Section 10(k). They also agreed that ILWU’s pursuit of a grievance in arbitration constituted a prima facie violation of Section 8(b)(4)(D). However, their respective viewpoints diverged on whether ILWU should have been permitted to raise a work-preservation defense to SSA’s Section 8(b)(4)(D) charge against ILWU.

Work-preservation defense. First, the court noted that there are two different doctrines called the “work-preservation defense” that were potentially relevant to this case. The first, set forth in NLRB v. International Longshoremen’s Ass’n (ILA), 447 U.S. 490 (1980), typically applies to unfair labor practice charges under Section 8(b)(4)(B), and draws a line between primary union activity, which is permissible, and secondary union activity, which is not.

According to the Board, this defense exists to separate permissible primary activity from impermissible secondary activity, and thus can only be invoked when a union is alleged to have engaged in secondary activity. Applying this defense in this context, argued the Board, would give every union an automatic defense to section 8(b)(4)(D) charges, gutting the Board’s section 10(k) authority to resolve jurisdictional disputes.

Instead, the Board contended that the only work-preservation defense that applies in this case is the one set forth in Highway Truck Drivers & Helpers, Local 107 (Safeway), 134 N.L.R.B. 1320 (1961). Under that doctrine, a union can compel the Board to drop section 8(b)(4)(D) charges and quash notice of a section 10(k) hearing if the union shows that the case is actually a “work preservation dispute” between the employer and the union, not a jurisdictional dispute between two unions.

Because all parties conceded that this was a classic jurisdictional dispute, the Safeway work-preservation defense did not apply. However, the Board argued that the jurisdictional nature of the dispute makes the ILA work-preservation defense inapplicable as well. The court noted that if it were starting from a blank slate, it might find this argument persuasive. However, this line of reasoning was foreclosed by the court’s decision in International Longshore and Warehouse Union v. NLRB (Kinder Morgan), 978 F.3d 625, (9th Cir. 2020).

Kinder Morgan. Kinder Morgan involved a jurisdictional dispute between ILWU and the Electrical Workers union. The Board awarded the work to the Electrical Workers and ILWU continued to seek the work by pursuing grievance procedures, prompting the Board to file an unfair labor practice charge against ILWU under Section 8(b)(4)(D).

ILWU invoked the work-preservation defense, which the Board rejected. The Ninth Circuit reversed the Board’s order holding that “[a] valid work-preservation objective provides a complete defense against alleged violations of section 8(b)(4)(D), as well as against jurisdictional disputes under section 10(k).” Thus, the court found that a union can avoid liability under Section 8(b)(4)(D) by satisfying the test outlined in ILA.

Here, the Board’s conclusion that the ILA work-preservation defense was inapplicable could not be reconciled with Kinder Morgan, said the court.

Secondary activity. Although the Board was correct in pointing out that Kinder Morgan also involved an allegation of secondary activity, this was not enough to carry its argument that the decision was inapplicable to the case at hand. The court noted that the secondary activity allegation was not the only allegation to which it held that the work-preservation defense applied.

The secondary boycott allegations in Kinder Morgan were brought under Section 8(b)(4)(B), observed the court. Thus, Kinder Morgan must mean that the ILA work-preservation defense provides a “complete defense against alleged violations of section 8(b)(4)(D)” in addition to allegations of secondary activity brought under section 8(b)(4)(B).

In conclusion, the court determined that Kinder Morgan compels it to hold that a union charged with an unfair labor practice under Section 8(b)(4)(D) may raise the ILA work-preservation defense even when the union is not alleged to have engaged in secondary activity. The Board’s refusal to entertain this defense was error, thus its order was vacated and the matter was remanded to the Board to evaluate the merits of the defense in the first place.

Concurrence. In a concurrence, Judge Miller wrote separately to express his view that Kinder Morgan was wrongly decided and should be reconsidered en banc, asserting that grafting the ILA work-preservation defense onto Section 8(b)(4)(D), as Kinder Morgan did, undermines the jurisdictional dispute-resolution scheme enacted by Congress.

The case is No. 23-632.

Judge: Miller, E.

Attorneys: Robert S. Remar (Law Office of Robert Remar) for International Longshore and Warehouse Union. Kira Dellinger Vol for the NLRB.

Companies: International Longshore and Warehouse Union

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