Detroit Diesel Corp. v. Martinrea Honsel Mexico SA de CV

• Court: Court of Appeals for the Sixth Circuit
• Decided: October 1, 2025
• Docket: 25-1280
• Status: Unpublished

Opinion

NOT RECOMMENDED FOR PUBLICATION File Name: 25a0446n.06

Case No. 25-1280

UNITED STATES COURT OF APPEALS FOR THE SIXTH CIRCUIT FILED Oct 01, 2025 ) KELLY L. STEPHENS, Clerk DETROIT DIESEL CORPORATION, ) Plaintiff-Appellee, ) ) ON APPEAL FROM THE UNITED v. ) STATES DISTRICT COURT FOR ) THE EASTERN DISTRICT OF MARTINREA HONSEL MEXICO SA DE ) MICHIGAN CV, ) Defendant-Appellant. ) OPINION )

BEFORE: SUTTON, Chief Judge; BATCHELDER and LARSEN, Circuit Judges.

SUTTON, Chief Judge. Auto-parts supplier Martinrea Honsel Mexico has a long-running

agreement to sell transmission components to engine-manufacturer Detroit Diesel. When

Martinrea threatened to stop making deliveries under the agreement, Detroit Diesel sought a

preliminary injunction against Martinrea. The district court granted the injunction, ordering

Martinrea to continue making deliveries for the next six months. That injunction expired on

September 30, 2025. We thus dismiss Martinrea’s appeal of the preliminary injunction as moot.

Detroit Diesel operates a manufacturing facility in Redford, Michigan, where it produces

truck engines, axles, and transmissions. In 2013, it signed a long-term contract with Martinrea to

purchase special-built transmission housings, which Detroit Diesel ordered through time-to-time

requests. No. 25-1280, Detroit Diesel Corp. v. Martinrea Honsel Mexico SA de CV

In 2024, Detroit Diesel filed a money-damages lawsuit against Martinrea that signaled the

beginning of the end of their 11-year relationship. Detroit Diesel alleged that Martinrea had

breached their contract by falling behind on its delivery obligations. Martinrea responded by

notifying Detroit Diesel that it would reject all future purchase orders, asserting that a recent

Michigan Supreme Court decision made the contract unenforceable. Detroit Diesel, in turn,

requested a preliminary injunction to compel delivery. After briefing and oral argument, the

district court granted Detroit Diesel’s request, ordering Martinrea to continue deliveries for the

next six months until September 30, 2025. The district court separately certified the enforceability

question to the Michigan Supreme Court and stayed the case through the duration of the

preliminary injunction.

Martinrea appealed the preliminary injunction, contesting only Detroit Diesel’s likelihood

of success on the merits. After the conclusion of the briefing, Detroit Diesel notified our court that

it would not seek an extension of the preliminary injunction. We asked the parties to brief whether

the appeal would become moot after September 30, 2025.

Article III of the United States Constitution limits the federal judicial power to “Cases”

and “Controversies.” U.S. Const. art. III, § 2. To respect that “cradle-to-grave” limitation, federal

courts must ensure that a live dispute persists throughout the case. Fialka-Feldman v. Oakland

Univ. Bd. of Trs., 639 F.3d 711, 713 (6th Cir. 2011). If, during the appeal, it becomes “impossible

for the court to grant any effectual relief,” a case or controversy no longer exists, and we must

dismiss the case as moot. Church of Scientology of Cal. v. United States, 506 U.S. 9, 12 (1992).

This appeal is moot. In Martinrea’s appeal, it asks only that we dissolve the preliminary

injunction. But once that injunction expired, it “required nothing of” and “meant nothing to”

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Martinrea. Fialka-Feldman, 639 F.3d at 714. We thus have no way to grant the requested relief,

making the appeal moot.

The possibility of Martinrea seeking damages for compliance with the preliminary

injunction cannot keep the appeal live. On-point cases from the Supreme Court and our own court

show why. In University of Texas v. Camenisch, a district court preliminarily enjoined the

university to pay for a deaf student’s sign-language interpreter. 451 U.S. 390, 391–92 (1981).

During the subsequent appeal, the student graduated, but the university tried to maintain the appeal

on the theory that a victory on the merits would allow it to recover those payments. Id. at 393.

The Court found the appeal moot, explaining that “it would be inappropriate . . . to intimate any

view on the merits” because “the only issue presently before [it] [was] the correctness of the

decision to grant a preliminary injunction.” Id. at 394, 398. Our decision in Marketing Displays

International v. Shaw followed the Supreme Court’s approach. 93 F.4th 967, 970 (6th Cir. 2024).

Shaw appealed a preliminary injunction, but the injunction expired before the parties finished their

appellate briefing. Id. Applying Camenisch, we rejected Shaw’s attempt to keep the appeal live

through the possibility of a yet-unfiled counterclaim. Id. Because “anything we might say about”

the preliminary injunction “wouldn’t affect Shaw’s ability to recover damages,” any ruling on the

merits would be an impermissible advisory opinion. Id. The same conclusion applies here.

Martinrea challenges this conclusion on two grounds, each unavailing. It first argues that

the appeal is not stale because a favorable ruling would resolve its planned (future) counterclaim

for the damages it incurred from complying with the preliminary injunction. A dispute, it is true,

remains live if granting “the relief sought would . . . make a difference to the legal interests of the

parties.” Id. (quotation omitted). And Martinrea, it is also true, may be able to recover damages

for complying with the preliminary injunction if it receives a favorable ruling on the merits. Id.

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But controlling caselaw prevents Martinrea from collecting these damages until it brings that claim

and obtains a “final judgment in [its] favor.” Camenisch, 451 U.S. at 397 (quotation omitted);

Shaw, 93 F.4th at 970. This appeal concerns only the preliminary injunction, which limits us to

deciding Detroit Diesel’s likelihood of success on the merits. See Brown v. Yost, 122 F.4th 597,

602 (6th Cir. 2024) (en banc) (per curiam). Because we cannot decide the ultimate merits of the

underlying dispute at this point, a favorable ruling on the preliminary injunction “wouldn’t affect

[Martinrea’s] ability to recover damages.” Shaw, 93 F.4th at 970. Martinrea’s ability to recover

damages at the end of this case cannot save this appeal from mootness. See Brown, 122 F.4th at

601–02 (citing Camenisch, 451 U.S at 394).

Martinrea also argues that the appeal fits within a mootness exception—that the

preliminary injunction is capable of repetition and of evading review. FEC v. Wis. Right to Life,

Inc., 551 U.S. 449, 462 (2007). This narrow exception applies to disputes that tend to become

moot before the litigation runs its course, such as an election or a labor strike, and are “likely

forever to evade review.” Lewis v. Cont’l Bank Corp., 494 U.S. 472, 481–82 (1990) (quotation

omitted). In this case, a live controversy remains as to the merits of Detroit Diesel’s breach-of-

contract damages claim. The “correctness of the decision to grant a preliminary injunction”

implicates “the same issue underlying the merits claim,” and so will not evade review by the

district court. Grupo Mexicano de Desarrollo, S.A. v. All. Bond Fund, Inc., 527 U.S. 308, 317

(1999) (quotation omitted). If Martinrea wants to contest that merits decision, nothing would stand

in the way of eventual appellate review.

We dismiss this appeal as moot and remand the case for further proceedings.