Federal Circuit Holds There is No ‘Presumption of Irreparable Harm’ on Preliminary Injunction Motions: What Took So Long?

On August 4, 2026, the U.S. Court of Appeals for the Federal Circuit (CAFC) chose to issue a precedential opinion formally holding that there is no “presumption of irreparable harm” in preliminary injunction proceedings in patent cases. The court acknowledged that this conclusion should have been apparent from the 2006 Supreme Court decision in eBay  Inc. v. MercExchange, L.L.C., 547 U.S. 388, 393-94 (2006).

In my personal opinion, this should have been apparent—and was apparent—well before 2006, and perhaps as early as 1983, when the presumption was first adopted by the Federal Circuit.

The Socket Solutions Case

Socket Solutions, LLC v. Import Global, LLC, ___F. 4^th___, 2026 U.S. App. LEXIS 23199, No. 2025-1121 (Fed. Cir., Aug. 4, 2026), was an appeal from a district court order granting a preliminary injunction in a patent case involving electrical wall outlet covers. The bulk of the decision was devoted to the question of whether the patentee had demonstrated a likelihood of success on the merits, and the entire focus of that analysis was on claim construction issues. The appeals court concluded that the District Court had erred in construing two claim terms. The court did not elaborate on exactly how these errors had impacted the analysis of the patentee’s likelihood of success. And nothing in this initial part of the opinion seems to explain the court’s decision to make the opinion precedential.

The court then turned to irreparable harm, and this is where the reason for a precedential opinion became clear. The Federal Circuit concluded that the District Court had also erred “to the extent it relied on a presumption of irreparable harm when a clear showing of patent validity and infringement has been made.” It concluded that this presumption cannot be justified after eBay. In invoking that presumption, the District Court had cited two Federal Circuit decisions which preceded the eBay decision.

As the Federal Circuit went on to explain in Socket Solutions, eBay involved the vitality of the presumption in the context of a request for a permanent injunction. The same was true of a more recent decision, Robert Bosch LLC v. Pylon Mfg. Corp., 659 F.3d 1143 (Fed. Cir. 2011), which had purported to “take the opportunity to put the question to rest and confirm that eBay jettisoned the presumption of irreparable harm as it applies to determining the appropriateness of injunctive relief.” The court concluded in Socket Solutions that there was no reason to depart from those holdings in the preliminary injunction context.

No reason indeed. It had always seemed to me that if there could be no presumption in the context of a permanent injunction (where there had been a full trial or summary judgment, such that the likelihood of success was 100%), how could there be a presumption when the likelihood of success was less certain?

eBay Is Not the Only Reason a Presumption of Irreparable Harm Is Wrong

In 2004—two years before eBay was decided—I co-authored, with a student at Rutgers Law School, an article in which we confronted head-on the presumption of irreparable harm in preliminary injunctions in patent cases, which had been on the books since Smith Int’l, Inc. v. Hughes Tool Co., 718 F. 2d 1573 (Fed. Cir. 1983). See Wepner & Ellis, The Federal Circuit’s Presumptively Erroneous Presumption of Irreparable Harm, 6 Tulane J. of Technology and Intellectual Property 147 (2004).

Our article advanced five arguments why Smith was wrong. One of them stressed that Smith was a procedurally unusual case. In Smith, there had been a full trial on the merits—and even an appeal—before the patentee sought what was characterized as a preliminary injunction, but which was (for all intents and purposes) a permanent injunction. At the time, as was later pointed out in eBay, the practice had long been that if a patentee prevails after trial, an injunction should be granted absent unusual circumstances. This is what was actually abolished in eBay. It would seem to me that while a presumption might be valid for permanent injunctions, that was not enough to extend it to preliminary injunctions. But if the presumption was “jettisoned” for permanent injunctions, it should have been totally off the table for preliminary injunctions. Now, finally, that is true as a matter of binding Federal Circuit precedent.

In writing our article, I recall being particularly fond of an argument that distinguished patent cases from trademark cases, where such a presumption in preliminary injunction proceedings had existed since long before Smith. We endorsed the presumption in trademark cases on the theory that damages are notoriously hard to prove in trademark cases, and confusion in the minds of actual and potential purchasers can never be undone, let alone compensated with money. In other words, as we put it, “eggs cannot be unscrambled.” In contrast, in patent cases, where confusion is not an issue, patent owners are statutorily entitled to damages adequate to compensate for the infringement under 35 U.S.C. §284.

I for one am delighted that, after a bump in the road, the presumption still (or again) prevails in trademark cases. Not long after eBay, the regional circuits, which handle most trademark appeals, fell into line in following eBay in preliminary injunction situations. See, e.g., N. Am. Med. Corp. v. Axiom Worldwide, Inc., 522 F. 3d 1211 (11^th Cir. 2008); Herb Reed Ents., LLC v. Fla. Entm’t Mgmt., 736 F. 3d 1239 (9^th Cir. 2013).

It took an act of Congress to restore the presumption of irreparable harm in trademark injunction proceedings, and Congress covered all the bases in doing so. As part of the Trademark Modernization Act of 2020, 15 U.S.C. §1116(a) was amended to state that a plaintiff seeking an injunction shall be entitled to a rebuttable presumption of irreparable harm upon a finding of a “violation” (e.g. infringement of a federally registered mark, or infringement of an unregistered mark under Section 43(a)) in the context of a motion for permanent injunction, or a finding of a likelihood of success on the merits in the context of a motion for preliminary injunction or a temporary restraining order.

It may have taken 43 years, but Socket Solutions now brings us back to where we were before the Smith case, and where we should be: a presumption of irreparable harm is available in trademark cases, and not in patent cases.

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Author: maxkabakov
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