An Opt-Out Is Not a Register Entry: Ownership and the Limits of Procedural Choice Before the UPC

The least reliable line in a European patent portfolio review is the one that looks most reliable. Opted out: yes. The field is binary, the source is public, and the answer takes four seconds to obtain. Nothing else in the file is that easy, which is exactly why the answer is believed.

It should not be. An entry in the register of the Unified Patent Court records that an application to opt out was lodged and processed. It does not record that the persons who lodged it were entitled to dispose of the right, that every proprietor of every national part took part, or that no earlier event had already fixed the jurisdictional position in the opposite direction. The entry is the trace of a procedural act. It is neither the act itself nor evidence that the act produced the intended result.

Two European patents can carry the same entry and end up in different courts. Both entries are accurate. The register answers a question about filings, while the parties read it as an answer about entitlement, and nobody has told them that these are two different questions.

A status field that decides nothing

The architecture is transitional by design. For seven years from the entry into force of the Agreement, an infringement or revocation action concerning a European patent may still be brought before national courts, and the Administrative Committee may extend that period by up to seven further years.1Within that window, a proprietor may notify the Registry of an opt-out, which takes effect when it is entered in the register, and may later withdraw it.2

That mechanism covers granted European patents, published applications and supplementary protection certificates, and it has produced a register of considerable size together with a habit of treating the resulting field as the answer. The Court of Appeal has already shown what the habit costs. In Neo Wireless v. Toyota Motor Europe, the German part of EP 3 876 490 had been assigned to a German entity while the opt-out for the whole bundle had been lodged by the American proprietor alone. The register displayed an opt-out. The Court of Appeal held that a valid application requires that it be lodged by or on behalf of all proprietors of all national parts of the European patent, and that the application before it was therefore ineffective.3The revocation action proceeded before the Court.

That question reached the panel as an objection to the competence of the Court, which is where such questions will keep arriving. The validity of an opt-out surfaces once someone has already invested in filing, and it is then decided against a factual record assembled years earlier by somebody else.

The reasoning matters more than the outcome. The default position of the legislator is that European patents fall within the jurisdiction of the Court unless they have been validly removed from it, and one proprietor cannot dispose of the procedural position of another without consent.4What decides whether the exclusion happened is entitlement. A register entry that reflects an application signed by one of two proprietors is a faithful record of an act that failed.

What the register records, and what nobody verifies

The application to opt out identifies the proprietors, the right concerned and the representative, and it carries the applicants’ own statement of their entitlement.5The Registrar enters it. That is an administrative operation performed on the declarations received, which is a different exercise from deciding, after argument, who held the right on the day of the filing.

A Hamburg panel put the point in unusually explicit terms in May 2026. Ruling on EP 2 581 193, it observed that the Registrar had been unaware of a pending German revocation action, and that no decision binding the Court had been taken on the validity of the withdrawal of the opt-out, the Registrar having decided only on the application submitted to him.6The register had accepted a withdrawal that the Court then held to be without effect.

The current Rules of Procedure confirm the diagnosis rather than cure it. Since 1 January 2026, a proprietor may apply to have an unauthorized opt-out or an unauthorized withdrawal removed from the register, the Registrar decides as soon as practicable, and the decision may be reviewed by the President of the Court of Appeal within one month.7A drafting choice of that kind rests on an assumption worth stating plainly: entries can be procured by persons who had no authority to procure them, and the system needs a route to clean them. The route is administrative. It sits alongside, and does not replace, the jurisdictional analysis that a panel will conduct if the point is raised on the merits.

Behind all of this lies a distinction the Hamburg order articulates with precision. For unitary patents the register determines proprietorship. For European patents the proprietor is the substantive owner, and the register status amounts to a rebuttable presumption.8A presumption allocates the burden of proof. It says nothing about what is true.

Registration constitutes the effect, entitlement constitutes the choice

Here is the proposition the practice has not yet absorbed. The opt-out is an act of disposition exercised over the procedural regime attached to a bundle of national rights, and it therefore belongs to whoever holds those rights. Registration is constitutive of the effect of that act, because the Agreement makes the opt-out operative upon entry. Registration is merely declaratory of its validity, because nothing in the entry establishes that the persons who signed could dispose of the right.

Two questions follow, and they are governed by different bodies of law. Who could dispose is a question of substantive title, answered by assignments, merger deeds, universal successions, employee invention transfers and, where the national parts have been distributed within a group, by the instruments that distributed them. When the choice became operative is a question of procedure, answered by the register.

The two questions can produce results that surprise the parties in either direction. The Hamburg order is the mirror image of Neo Wireless and confirms the same thesis from the opposite side. The opt-out had been filed in March 2023 by the entity that was then both the registered and the material owner of the patent.9A later entitlement judgment transferred the patent to the claimant, but under German law such a judgment operates ex nunc, without retroactive effect, so the transfer could not unmake a choice that had been validly made when it was made. The opt-out stood, and the Court declined jurisdiction over the infringement action.

Life sciences portfolios show how quickly the list of required signatories grows. An opt-out extends to any supplementary protection certificate based on the European patent, and where a certificate has already been granted its holder must lodge the application together with the patent proprietor if the two differ.10Certificates are national titles, frequently held by the entity that obtained the marketing authorisation in that country, sometimes a local subsidiary and sometimes a commercialisation partner. A single European patent may therefore require signatures from the proprietor of the bundle and from several certificate holders that appear nowhere in the patent register, with the composition of that group changing from one designation to the next. A centrally managed portfolio can be centrally mismanaged in exactly this way, because the person who filed knew the patent and not the certificates.

That reasoning carries a consequence which deserves more attention than it has received. The temporal effect of an ownership judgment is a matter for the national law that governs the transfer. A system that treats a successful entitlement claim as retroactive would not necessarily reach the same result on the same facts. The jurisdictional status of a European patent bundle can therefore depend on the law of the national part in which the ownership dispute was decided, which is precisely the kind of fragmentation the transitional regime was expected to contain rather than to generate.

Two clocks, and the events that stop them

Anyone auditing an opt-out is really auditing two clocks.

The first runs to the date of the filing and asks who was entitled on that day. The second runs forward from it and asks whether an event has since fixed the position. Both are unforgiving, and neither is visible in the status field.

The blocking events are set out in the Agreement and refined by the Rules. An opt-out is ineffective if an action has already been brought before the Court before the entry is made.11A withdrawal is ineffective if an action has been brought before a national court. The scope of that second rule was decided in AIM Sport Development v. Supponor, where the Court of Appeal held that the actions capable of preventing a withdrawal are those commenced during the transitional period, so that litigation begun before the Agreement entered into force does not block the return to the Court, and confirmed that Article 83(4) prevails over the Rules of Procedure in case of inconsistency.12The blocking event has a window, and the window has a start date.

Two features of that first rule are easily missed. It applies irrespective of whether the earlier action before the Court is pending or has already been concluded, so a discontinued claim filed days before the entry can still defeat the opt-out. And the reference point is the date of entry in the register, not the date of the application, which turns the processing interval into a period of exposure that the proprietor does not control.

It also has a definition borrowed from elsewhere. In the Hamburg case, the withdrawal lodged on 4 February 2026 failed because a revocation action against the German part had been brought before the Federal Patent Court on 9 January 2026, and the moment at which that action was brought was determined by German procedural law, namely receipt of the statement of claim by the court.13Whether a national action was commenced in time is thus a question of local procedure, resolved by rules the party planning the withdrawal may never have consulted.

One further event removes the choice without anyone deciding to remove it. Where an application subject to an opt-out proceeds to grant as a European patent with unitary effect, the opt-out is deemed to have been withdrawn and the Registrar enters that withdrawal.14A portfolio strategy that opts out at application stage and later requests unitary effect for the same right has, without a further decision and often without a further conversation, placed the patent back within the exclusive jurisdiction of the Court. Combined with the prohibition on opting out again after a withdrawal, the sequence is worth mapping before it is executed rather than after.

Practitioners should draw the operational inference. A national revocation action now does double duty. Beyond the attack on validity, it can freeze an opponent’s route back to the Court, and it is available to whoever files first and knows the local rule on commencement. The party that controls the timing of a national filing controls the other side’s route back to the Court. And since a patent whose opt-out has been withdrawn cannot be opted out again, the manoeuvre is played on a board where one of the two moves is irreversible.15

The certainty objection, and five dates that answer it

The serious objection to everything written above is legal certainty, and it should be stated at its strongest.

Jurisdiction is supposed to be knowable in advance. A competitor deciding whether to attack a patent centrally, a licensee assessing its exposure, a purchaser pricing a portfolio: none of them can audit a chain of title they do not own, and none of them has access to the unrecorded instruments on which, on this analysis, the answer depends. If the validity of an opt-out turns on facts that are invisible to everyone except the proprietor, then the only public source becomes decorative, forum selection becomes a wager, and the removal procedure introduced in 2026 protects the proprietor who was wronged without helping the third party who was misled.

The objection is real and cannot be dissolved by asserting that diligence solves it. What answers it is that certainty here is produced by rules of evidence rather than by a fiction about the register. Three features already do most of the work. The presumption attached to the register places the burden on the party who challenges the entry, so the proprietor who filed correctly is not required to prove its title every time it enforces. The default identified by the Court of Appeal resolves residual doubt in favor of the Court’s jurisdiction, so uncertainty produces access rather than denial. The removal procedure offers a cheap administrative route to clear a defective entry instead of litigating jurisdiction at the merits stage of a case that has already cost both parties a year.

A residual cost remains, and honesty requires naming it. The party with the least information is often the one obliged to invest in the search. That cost is better priced than concealed, and it is one more reason why the institutional credibility of the transitional regime deserves the attention I have argued elsewhere it does not receive.16

Pricing it requires a method. Five dates decide the jurisdictional status of any European patent within the transitional regime, and a file that cannot evidence all five has not established the status it asserts.

The first is the date the application to opt out was lodged, together with the identity of every person who held substantive title on that day, evidenced by the instruments themselves rather than by a register extract taken later. The second is the date of entry in the register, which fixes the moment from which the opt-out operates and before which a UPC action defeats it. The third is the date of any action brought before the Court prior to that entry. The fourth is the date of any national action brought during the transitional period, computed under the procedural law of the country concerned rather than by analogy with a familiar one. The fifth is the date and the legal character of every ownership change since, including whether the applicable national law gives an entitlement judgment prospective or retroactive effect.

Three questions inside that grid cannot be answered from public sources. Which instrument established title on the day of the filing, and was it complete on that day or only signed. Whether every proprietor of every national part participated, including entities holding a single designation after an internal reorganisation. When, under the relevant national procedural rule, an action was brought, as distinct from when it was announced, served or reported.

A patent family unable to answer those questions is described incorrectly as an asset, because what is being valued is an enforcement route that may not exist.

The register records what was filed. The file records what was decided, by whom, and on which day. Portfolio jurisdiction is not a status to be read before a dispute. It is a fact to be proved, and the proof is assembled long before anyone needs it.

• 1Agreement on a Unified Patent Court, Article 83(1) and (5).
• 2Agreement on a Unified Patent Court, Article 83(3) and (4); Rules of Procedure of the Unified Patent Court, Rule 5.5 and Rule 5.7.
• 3UPC Court of Appeal, second panel, order of 4 June 2024, UPC_CoA_79/2024, APL_9578/2024 (appeal from UPC_CFI_361/2023), Neo Wireless GmbH & Co KG v. Toyota Motor Europe NV/SA, para. 50, https://www.unifiedpatentcourt.org/sites/default/files/files/api_order/5F9795874E86966B3D3A6B1A61BC2143_en.pdf.
• 4Ibid., paras 17, 20, 33, 34 and 38; Rules of Procedure, Rule 5.1(a).
• 5Rules of Procedure of the Unified Patent Court, Rule 5.3, https://www.unifiedpatentcourt.org/sites/default/files/upc_documents/Consolidated%20Rules%20of%20Procedure%20UPC_EN.pdf.
• 6UPC Court of First Instance, Local Division Hamburg, order of 7 May 2026, UPC_CFI_481/2026, Silimed Indústria de Implantes Ltda and Silimed GmbH v. Polytech Health & Aesthetics GmbH and others, para. 49, https://www.unifiedpatentcourt.org/sites/default/files/files/api_order/UPC_CFI_481-2026.pdf.
• 7Rules of Procedure of the Unified Patent Court, Rule 5A, in the consolidated version entering into force on 1 January 2026.
• 8Silimed, cited above, para. 37.
• 9Ibid., paras 31, 34 and 35.
• 10Rules of Procedure of the Unified Patent Court, Rule 5.2.
• 11Agreement on a Unified Patent Court, Article 83(3); Rules of Procedure, Rule 5.6.
• 12UPC Court of Appeal, second panel, order of 12 November 2024, UPC_CoA_489/2023 and UPC_CoA_500/2023, APL_596007/2023 and APL_596892/2023, AIM Sport Development AG v. Supponor Oy and others, EP 3 295 663, paras 32, 35 and 37, https://www.unifiedpatentcourt.org/sites/default/files/files/api_order/12B21CBC1FBCB93A97568A538CAA390D_en.pdf.
• 13Silimed, cited above, paras 41, 42 and 45.
• 14Rules of Procedure of the Unified Patent Court, Rule 5.9.
• 15Rules of Procedure of the Unified Patent Court, Rule 5.10.
• 16M. Dhenne, “The World Without the UPC: How a Successful Court Could Still Disappear”, Kluwer Patent Blog, 9 June 2026.