When the Unified Patent Court (UPC) opened on 1 June 2023, the decision facing every holder of a European patent was framed as a risk-management reflex rather than a strategic choice. A new supranational court could, in a single proceeding, revoke a classical European patent with effect across every UPC Member State in which it was in force; the safe move, absent any track record of how that court would decide, was to keep the crown jewels out of its reach. Portfolio owners opted out in volume during the sunrise window that preceded the Court’s opening, with pharmaceutical patents among the most heavily opted out.1Agreement on a Unified Patent Court [2013] OJ C175/1 (UPCA), Art. 83; Rules of Procedure of the Unified Patent Court, r. 5. On sector opt-out patterns, see the opt-out analyses referred to at n 4. Three years on, the Court has passed its third anniversary, and the reflex can now be tested against a body of decided cases. The picture that has emerged is neither the run-away revocation machine some feared nor the neutral forum others hoped for, and for a US-headquartered life-sciences company the original opt-out, made blind, is worth re-opening before the transitional period that permits it runs out.
1. The Decision Most US Portfolios Deferred
The choice is unusually consequential for US companies for a structural reason. A US biotech or pharmaceutical group typically holds its European rights as a bundle of national validations of a granted European patent, obtained through the European Patent Office (EPO) and then split into German, French, Italian, Dutch and other territorial parts. That bundle is precisely the object Art. 83 UPCA lets a proprietor opt out, and it is precisely the object the UPC can otherwise revoke in one stroke. The unitary patent, by contrast, is inseparable from the Court: it exists only because the UPC exists, cannot be opted out, and lives or dies before the UPC alone.2Regulation (EU) No 1257/2012 implementing enhanced cooperation in the area of the creation of unitary patent protection [2012] OJ L361/1; UPCA (n 1), Art. 32 (exclusive competence over unitary patents and, subject to the transitional regime, classical European patents). So the opt-out question only ever concerned the classical validations, and those are the assets a US portfolio most often treats as its European core.
Because the opt-out had to be lodged before any UPC action touched the patent, the decision was front-loaded into 2023, when there was nothing to reason from. Most owners resolved the uncertainty conservatively and opted out, deferring the real strategic question, whether the Court is a forum to fear or to use, to a later day that has now arrived. The early caution was reasonable on its own terms; what has changed is that the facts it stood in for now exist, and they do not all point the same way.
2. What Article 83 Gives, and the Gate It Closes
Article 83 UPCA builds a transitional regime lasting seven years from the Court’s opening, which the Administrative Committee may extend by up to a further seven years after a review conducted five years in. Absent a prolongation decided under Art. 83(5) UPCA, the transitional period expires on 1 June 2030, and an opt-out has to reach the Registry no later than one month before that expiry. During it, an action on a classical European patent may still be brought before the national courts, and a proprietor may opt a patent or a published application out of the UPC’s competence altogether by notifying the Registry, an opt-out that carries with it any supplementary protection certificate (SPC) based on that patent.1 An opt-out is made per patent, takes effect on entry in the register, and once made it endures for the entire remaining life of the patent, not merely to the end of the transitional period. It removes the patent from the UPC and returns it to the mosaic of national courts for both infringement and validity.
The opt-out is easy to enter and, in the case that matters most, impossible to leave. Its value therefore has to be judged not against today’s litigation posture but against every dispute the patent might see for the rest of its term.
The asymmetry sits in the withdrawal rule. Article 83(4) UPCA lets a proprietor withdraw an opt-out, that is, opt the patent back into the UPC, at any time, but not once an action concerning that patent has been brought before a national court. The Court of Appeal has read that limitation narrowly. In AIM Sport Development v Supponor it held that only national actions brought during the transitional period lock the patent out of withdrawal, so that a national dispute begun before 1 June 2023 does not forever bar a later opt-in; but the corollary is unchanged and severe: once a qualifying national infringement or revocation action has been commenced at any point in the transitional period, whether before or after the opt-out and whether brought by the proprietor or against it, the door back into the UPC shuts for good, and a patent whose opt-out has once been withdrawn cannot be opted out a second time.3UPC Court of Appeal, AIM Sport Development AG v Supponor Oy and others, UPC_CoA_489/2023 and UPC_CoA_500/2023 (order of 12 November 2024), interpreting Art. 83(4) UPCA and r. 5.8 of the Rules of Procedure: a national action commenced before the start of the transitional period does not preclude withdrawal of an opt-out. A patent whose opt-out has been withdrawn may not be opted out again (r. 5.10). Which actions qualify is settled in one direction and open in another: on subject matter the Court of Appeal has read the trigger in Art. 83 UPCA as reaching every action within the Court’s own competence and no other, which is what the Rules of Procedure already said; but the Rules confine the trigger to proceedings before a court of a contracting Member State, while Art. 83(4) UPCA speaks of an action brought before a national court without saying whose. A competitor who wants to keep a US originator’s patent out of the UPC can therefore engineer that result unilaterally, by commencing a national action before the courts of a single contracting Member State, converting the originator’s reversible opt-out into a permanent one. The opt-out is thus better understood as a one-shot option the patentee holds but a rival can cancel, and that structural feature, more than the headline revocation risk, is what gives the choice its strategic weight.
3. Three Years of Data: Where the Court Actually Bites
The record now available, in the Court’s own annual statistics and in the practitioner reviews published at its third anniversary, answers the question the 2023 decisions could only guess at. The Court has been busy and its business is concentrated. Infringement actions, not revocations, dominate the docket, with 164 infringement actions initiated in 2024 and 266 in 2025, and the overwhelming majority filed in the German local divisions, which have accounted for the large majority of both preliminary-injunction requests and infringement actions.4Caseload and opt-out figures drawn principally from the UPC Annual Reports 2024 and 2025, outcome figures from practitioner three-year reviews (2026): infringement actions of 164 (2024) and 266 (2025); German divisions accounting for 70% of preliminary-injunction filings and 76% of infringement main actions; a preliminary-injunction grant rate of c. 60% across the decided applications; US entities as c. 44% of PI applicants; electricity (IPC H) leading and human necessities (IPC A) second among the technical fields. Opt-out applications reached 469,749 by the end of the sunrise period and 662,012 by 31 December 2025, with pharmaceutical patents over-represented. Preliminary injunctions, the remedy that most frightens a defendant, are granted in about sixty percent of the applications the Court has decided. The largest technical field before the Court is electricity, the section that carries the standard-essential-patent docket, and human necessities is the second, at 105 and 56 respectively of the patents drawn into the infringement and revocation actions lodged in 2025; life sciences sits close to, without occupying, the center of gravity of the Court’s docket.
Two figures speak directly to US portfolios. US entities are among the most frequent defendants in standalone revocation actions, and among the most frequent applicants for preliminary injunctions, which means US companies are already both wielding the Court and being pursued in it more than the opt-out rhetoric of 2023 would suggest.4 The validity outcomes distribute as follows: across the decided infringement actions in which revocation was counterclaimed, just over half of the patents were maintained as granted and a further sixth in amended form, while roughly a third were revoked.4 What that aggregate implies for any particular patent is not readable off it.
4. The Long Arm After BSH v Electrolux
The single development that most unsettles the 2023 arithmetic did not come from the UPC at all. In BSH Hausgeräte v Electrolux the Court of Justice of the European Union (CJEU) held that a court of the Member State where a defendant is domiciled may hear an infringement action covering all national parts of a European patent, including parts validated in other Member States, and that a validity challenge to a foreign-validated part does not strip that court of its jurisdiction over infringement; it may even rule, with effect between the parties only, on the validity of a patent granted in a non-Union third state, unless a convention preserved by Art. 73 of the Brussels I bis Regulation reserves that question, as the Lugano Convention does for Switzerland, Norway and Iceland.5Case C-339/22 BSH Hausgeräte GmbH v Electrolux AB, ECLI:EU:C:2025:108 (CJEU, Grand Chamber, 25 February 2025), on Art. 4(1) and Art. 24(4) of Regulation (EU) No 1215/2012 (Brussels I bis): the domicile court retains jurisdiction over infringement of foreign-validated European patent parts notwithstanding a validity defense, and may rule inter partes on the validity of a third-state patent, save where Art. 73(1) preserves the exclusive validity jurisdiction of a State party to the 2007 Lugano Convention, as Switzerland is. UPC divisions had begun to test that reach before the ruling was delivered, and have since treated it as a warrant for their own long arm, entertaining claims that extend beyond the contracting Member States to national parts of a European patent in other jurisdictions, whether because the defendant is itself domiciled within the UPC’s territory or because it is drawn in as a co-defendant to one that is.
For a US portfolio the consequence is double-edged, and it changes the meaning of both postures. Staying in the UPC, or opting back in, now offers a claimant a forum that may adjudicate infringement not just across the UPC states but across a wider European footprint in one action, which raises the offensive value of UPC access for a US patentee enforcing against a European-domiciled competitor. But the same expansion cuts against the defensive premise of the opt-out, because BSH concerns the jurisdiction of national Member-State courts under the Brussels regime, and opting a patent out of the UPC returns it to exactly those courts, several of which may now assert a broader cross-border reach than they did in 2023. The opt-out was sold as a way to keep disputes small, national and predictable; after BSH the national forum it hands the patent back to is itself a potential cross-border venue. Neither door leads back to the contained, one-country litigation the original opt-out was meant to preserve.
5. Why the Calculus Is Sharper for Biotech
Three features of life-sciences patenting make the opt-out decision heavier for a biotech portfolio than for most others. The first is concentration of value. A small-molecule or biologic franchise frequently rests its European exclusivity on one or a few compound and second-medical-use patents, so the loss of a single patent in a single UPC proceeding is not a portfolio dent but a franchise event. The Court of Appeal’s decision in the Amgen v Sanofi and Regeneron dispute over PCSK9-inhibitor antibodies, which reversed the Munich central division’s revocation of Amgen’s patent and clarified how the UPC assesses inventive step, in particular the requirement of a reasonable expectation of success rather than mere hope, shows both that biologics claims are being litigated to final European determinations at speed and that the substantive validity standard is still settling as it goes.6UPC Court of Appeal, Amgen Inc v Sanofi and Regeneron, UPC_CoA_528/2024 and UPC_CoA_529/2024 (25 November 2025), reversing the Munich central division’s revocation of Amgen’s patent EP 3 666 797 and maintaining it; the Court of Appeal set out the UPC’s own inventive-step approach, on which a reasonable expectation of success (a rational prediction of success), not mere hope, is required.
The second is that the UPC’s life-sciences case law began, and continues, with the fast remedy. The first inter partes preliminary injunction the Court granted, in 10x Genomics v NanoString, was a life-sciences dispute later overturned on appeal, and the pattern since is of biotech and medical-device patentees testing the Court’s injunctive muscle early. For a US company whose European launch depends on freedom to operate, the possibility that a competitor obtains a UPC-wide preliminary injunction in a matter of months is a live scenario, and it arises in the field where the Court has been most active.710x Genomics v NanoString, UPC_CFI_2/2023 (Munich Local Division, preliminary injunction of September 2023), widely regarded as the UPC’s first inter partes PI, set aside by the Court of Appeal (UPC_CoA_335/2023, 26 February 2024). Illustrative of the Court’s early concentration in life sciences and of the appellate correction rate on PIs.
The third is the supplementary protection certificate and the geography of where such disputes are heard. With the opening of the Milan section of the central division on 27 June 2024, the Court’s central-division work was divided three ways: Munich took chemistry alongside the mechanical fields it already held, Milan took human-necessities patents in International Patent Classification (IPC) section A other than those carrying an SPC, and Paris acquired exclusive competence over all SPC matters regardless of the underlying product’s classification. Because a pharmaceutical franchise’s later-life European exclusivity often turns on an SPC layered over a basic patent, and because the basic patent and its SPC can now be routed to different seats while their opt-out status cannot be split, the exposure on a life-sciences asset has to be read patent by patent and certificate by certificate even though the opt-out itself moves them as one.8UPC Administrative Committee decision reallocating the former London central-division competences; the Milan section opened on 27 June 2024 and hears IPC section A (human necessities) patents without SPCs, Munich hears IPC section C (also without SPCs) and section F, and Paris hears the remaining sections and all SPCs. An SPC and its basic patent may accordingly fall to different seats, but their opt-out status cannot be split: an opt-out, or its withdrawal, extends to any SPC based on the patent (r. 5.2 of the Rules of Procedure).
6. Strategic Considerations for US Portfolios
The unifying question is no longer whether to fear the UPC but which patents belong in it, and that question resolves into several that a US portfolio owner can no longer answer by default. Which assets carry genuine pan-European enforcement value, such that single-action injunctive reach against a European-domiciled infringer would be worth the exposure, and which are defensive holdings whose only realistic UPC role is as a revocation target? Whether the Court’s injunction practice and its post-BSH reach have moved that balance in either direction is a judgment that turns on the individual asset, and on the same patent the two pull opposite ways.
How reversible is the opt-out in practice for the specific patents at issue? Because withdrawal is barred once a qualifying national action has been commenced, the opt-out on a commercially important patent is only notionally reversible: a single competitor can foreclose the opt-in by commencing a national action before a court of a contracting Member State in a matter within the Court’s own competence, and the patent may already carry such an action from earlier in the transitional period without anyone having treated it as a UPC event. Which patents are already, or are about to become, the subject of national proceedings that would lock their status either way, and does the sequencing of a planned enforcement campaign have to account for that lock before the first shot is fired?
Does the existing contract base still describe the right that now exists? In-licenses, co-development agreements and acquisition documents drafted before or during the UPC’s opening frequently allocate control of “European patent litigation,” or the right to decide opt-outs, in language that did not anticipate a forum in which one proceeding disposes of the whole European bundle, and on an inbound biotech asset it is frequently not determinable from those documents which party now holds a decision that moves in each direction only once. And a jurisdictional question a US team is least likely to frame for itself: Switzerland is neither a Member State nor a party to the UPCA, so the Swiss part of a European patent can be neither opted out nor revoked by the UPC, and its validity is reserved to the Bundespatentgericht (the Swiss Federal Patent Court) on its own timetable, a reservation the Court of Justice expressly preserved in BSH for States party to the Lugano Convention. What the post-BSH case law has changed is narrower and easy to miss: a UPC division seised of a defendant domiciled in a contracting Member State may nonetheless rule on infringement of that Swiss part, so a “European” strategy built around the UPC neither disposes of the Swiss track nor leaves it untouched.9Switzerland is not a Member State of the European Union and is not a contracting party to the UPCA (n 1); the validity of Swiss designations of a European patent granted by the EPO remains subject to the exclusive jurisdiction of the Bundespatentgericht (Federal Patent Court) under the Patentgerichtsgesetz (PatGG) vom 20. März 2009 (SR 173.41). The UPC’s competence and the Art. 83 opt-out regime do not extend to Swiss patent rights, though infringement of a Swiss designation may be heard by the court of a defendant’s domicile.
None of these questions has a portfolio-wide answer, which is the practical point. The 2023 opt-out was a single switch thrown across an entire portfolio in the absence of data; what the record since has exposed is that the switch is not one switch but one per patent, that it moves in each direction only once, and that a competitor’s filing can freeze it where it stands. These are questions that require analysis tailored to specific patents, commercial objectives, and the litigation posture of likely adversaries.