Janssen-Cilag Limited v The United States of America [2026] EWHC 1532 (Pat)

[2026] EWHC 1532 (Pat)Case No HP-2026-000007
IN THE HIGH COURT OF JUSTICE
BUSINESS AND PROPERTY COURTS OF ENGLAND AND WALES
INTELLECTUAL PROPERTY LIST (ChD)
PATENTS COURT
Venue Royal Courts of Justice, Rolls Building, Fetter Lane, London, EC4A 1NLDate 22 June 2026
Before
THE HON MR JUSTICE MELLOR
Between
JANSSEN-CILAG LIMITEDClaimant/THE UNITED STATES OF AMERICADefendant/
Justin Turner KC and Michael Conway (instructed by Herbert Smith Freehills Kramer LLP) for Claimant/RespondentProfessor Dan Sarooshi KC and Ian McDonald (instructed by Bristows LLP) for Defendant/ApplicantHearing Hearing dates: 5 June 2026. Draft Judgment to the parties 16 June 2026.
APPROVED JUDGMENTThis judgment was handed down remotely by circulation to the parties’ representatives by email.It will also be released for publication on the National Archives and other websites. The date andtime for hand-down is deemed to be Monday 22 June 2026 at 10.30am.THE HON MR JUSTICE MELLOR

Introduction

[1]The Defendant, the United States of America, as represented by the Secretary, Department of Health and Human Services, applies to set aside service of this claim against it. The Defendant is the registered proprietor of a European Patent (UK), and the Claimant seeks revocation of it in this claim.[2]The application before the Court was principally concerned with ss.12(1), 12(6) and 12(7) of the State Immunity Act 1978 (“the SIA” or “the SIA 1978”). Section 1 of the SIA is headed ‘General immunity from jurisdiction’ and provides:
‘(1) A State is immune from the jurisdiction of the courts of the United Kingdom except as provided in the following provisions of this Part of this Act. (2) A court shall give effect to the immunity conferred by this section even though the State does not appear in the proceedings in question.’
[3]Sections 2-11 fall in the next section of the SIA which is headed ‘Exceptions from immunity’. Each of those sections provides a ‘State is not immune’ in certain particular situations indicated by their headings. I will mention later some particular aspects of those sections which were relied upon.[4]Section 12 of the SIA sits under the heading of ‘Procedure’ and is mainly concerned with service of process. The relevant provisions (as amended) are as follows:
‘(1) Any writ or other document required to be served for instituting proceedings against a State shall be served by being transmitted through the Foreign, Commonwealth and Development Office to the Ministry of Foreign Affairs of the State and service shall be deemed to have been effected when the writ or document is received at the Ministry. (2) Any time for entering an appearance (whether prescribed by rules of court or otherwise) shall begin to run two months after the date on which the writ or document is received as aforesaid. (3) A State which appears in proceedings cannot thereafter object that subsection (1) above has not been complied with in the case of those proceedings. (4) No judgment in default of appearance shall be given against a State except on proof that subsection (1) above has been complied with and that the time for entering an appearance as extended by subsection (2) above has expired. … (6) Subsection (1) above does not prevent the service of a writ or other document in any manner to which the State has agreed and subsections (2) and (4) above do not apply where service is effected in any such manner. (7) This section shall not be construed as applying to proceedings against a State by way of counter-claim or to an action in rem; and subsection (1) above shall not be construed as affecting any rules of court whereby leave is required for the service of process outside the jurisdiction.’
[5]In more detail, the application was the Defendant’s application to set aside the service of this claim against it pursuant to the Orders of HHJ Hacon dated 25 February and 4 March 2026. In essence, the Claimant secured those Orders on the basis that this claim for revocation of a patent is ‘an action in rem’, within the meaning of s.12(7) of the SIA, such that s.12(1) did not apply.[6]Subsequently, after discovering that the Defendant had filed an address for service with the United Kingdom Intellectual Property Office (“UK IPO”), the Claimant’s representatives also served the proceedings at that address. This gave rise to an alternative basis for service pursuant to section 12(6).[7]The issues under the SIA arise in the following circumstances.[8]In this action, the Claimant seeks an order for revocation of EP(UK) 3,689,383 B1 entitled ‘Chimeric Antigen Receptors Targeting B Cell Maturation Antigen’ (‘the Patent’). The Claimant is a subsidiary of Johnson & Johnson, the healthcare and pharmaceutical company, which has developed “Carvykti”: an innovative treatment for patients suffering relapsed or refractory multiple myeloma (“MM”) (a type of bone marrow cancer). Carvykti provides personalised therapy based on modifying a patient’s T-cells with a receptor, called a chimeric antigen receptor (“CAR”), which binds a particular antigen on MM cells. The Claimant holds the UK marketing authorisation for Carvykti, and I will refer to the Claimant as “J&J”.[9]The Defendant (hereafter “the USA” or “the USDH”) is the registered proprietor of the Patent. 2seventy bio (“2seventy”), a subsidiary of Bristol Myers Squib, has a licence to the Patent (which it claims in the UPC proceedings referred to below is an exclusive one) under which it markets Abecma, an alternative CAR-T cell based therapy for MM. In the UPC proceedings it is said by 2seventy that Carvykti falls within the scope of the Patent.[10]The claim form was issued, along with the Particulars of Claim and the Grounds of Invalidity, on 5 February 2026.[11]On 5 June 2026 I heard the application of the Defendant by notice dated 7 April 2026 by which it sought to challenge service of these proceedings and hence the jurisdiction of the Court (“the Set Aside Application”). Having done extensive pre-reading with the aid of the very useful Skeleton Arguments from each side, and following nearly a full day of oral submissions, at the conclusion of submissions I announced at least part of the result – I declared that the USA had been validly served pursuant to section 12(6) of the SIA when the proceedings were served, on 23 March 2026, at the address for service listed on the Register of Patents held at the UK IPO. I left over the outcome of the more involved issue which arose over the proper interpretation, in section 12(7) of the SIA, of the phrase ‘an action in rem’. This judgment contains my reasons on both these issues.[12]At the outset, it is necessary to keep in mind what the phrase ‘action in rem’ actually signifies, along with its counterpoint an ‘action in personam’. In an ‘action in personam’ the Court exercises personal jurisdiction i.e. against a natural person or a body which exists in law. By contrast, in an ‘action in rem’, the jurisdiction of the Court is (at least initially) exercised against the res (the thing). See further below. Procedural background The UPC infringement proceedings

Procedural background

[13]The Patent was granted on 31 December 2025.[14]On 5 January 2026, 2seventy brought proceedings in the Unified Patent Court alleging infringement of the Patent by J&J in respect of Carvykti and seeking damages, and in the alternative injunctive relief, across UPC signatory states. J&J noted that the injunction sought in those proceedings is conditional on certain damages not being awarded and would only take effect after determination of the later of the final decision, including appeal, in the UPC or EPO opposition proceedings.[15]On the evidence before me, the UPC action is anticipated to proceed quickly. It is likely that a first instance hearing will take place in Q1 2027, and a decision may follow shortly thereafter.[16]To date, 2seventy has not brought a claim for infringement in the UK. It has, however, indicated that it may do so “as a result of the commencement of [these] Proceedings”. J&J observed that it is unclear why commencing these revocation proceedings should have impacted on 2seventy’s assessment of the merits or otherwise of bringing an infringement claim here, though they noted that, had 2seventy done so at an earlier date, it would have required the USA to be joined either as co-claimant or as a third party to such proceedings, in which case J&J would have had no difficulty serving a revocation action on the USA brought by way of counter-claim (see the terms of s.12(7) of the SIA, set out above). J&J say that it is now clear that there is a very real threat of J&J facing infringement proceedings in the UK as well as the UPC.[17]The USA was named as the proprietor of EP 383 in 2seventy’s particulars of claim for the UPC action, and the Munich address of Grünecker (the USA’s patent attorneys) was listed as the USA’s address for service. There are indications that the USA has been actively coordinating with 2Seventy in respect of its litigation strategy in the UPC and EPO. On 17 April 2026 the USA applied to be joined to the UPC action as an intervenor. For these purposes, it also requested that all notifications and communications in the proceedings be effected on the physical and/or email address of its nominated representatives – based at Trevisan & Cuonzo, in Milan.[18]J&J observed that it is a striking feature of the USA’s position that it is actively seeking to enforce the Patent against J&J in the UPC by coordinating with 2seventy, and now directly participating in the UPC proceedings, and for those purposes is content to accept service at its representatives’ address.[19]At the same time as making the request to intervene, the USA made an application under Rule 9.1 of the UPC Rules of Procedure to change the address for service to an address of the National Institutes of Health in Maryland, US. Prior to that point, the address for service of the proprietor had been listed as Grünecker’s Munich address.[20]The UPC made an order allowing the application to intervene and to permit service via Trevisan & Cuonzo in Italy – noting that the parallel request to add the US address was “contradictory and creates confusion”.

EPO Opposition

[21]Opposition proceedings in respect of EP 383 are ongoing at the EPO. However, J&J’s position is that these proceedings will not give it certainty in relation to its current and planned activities in the UK within the required timeframe. Even on an accelerated timeframe, opposition proceedings would not be decided until approximately Q2 2027 and a decision from any appeal is likely to take at least a further 12 months.

Service of these revocation proceedings in the UK

[22]Following the issue of these revocation proceedings on 5 February 2026, J&J filed an application for permission to serve the USA by alternative methods (“the Service Application”) on 9 February 2026, which was heard before HHJ Hacon on 25 February 2026. J&J argued that in view of the urgency of the proceedings, permission for alternative service was necessary to avoid the lengthy delay entailed by serving proceedings in accordance with s.12(1) SIA, or in accordance with Art.5 of the Hague Service Convention 1965 (‘HSC 1965’). Having decided that s.12(1) SIA (and therefore also the provisions of CPR 6.44), did not apply to these proceedings, the Judge accepted that J&J had established that there was sufficiently good reason to order service by alternative means, as required by CPR 6.15.[23]The USA filed an Acknowledgement of Service indicating its intention to challenge jurisdiction on 20 March 2026 and filed the Set Aside Application on 7 April 2026. It did not prove possible to have the hearing of this Application until 5 June 2026, due to the congested Court diary.

The issues for decision

[24]Although my decision under section 12(6) was sufficient to determine the service issue, Counsel for the USA made it clear that they wished me to decide the issue under s.12(7) (and effectively whether HHJ Hacon was correct to make his Order(s)), in case his Judgment was deployed against the USA in the future. In view of the substantial argument on the point (and also the costs consequences), I acceded to that request.[25]During the hearing, Counsel for J&J accepted that, if I was against them on the section 12(7) point (and subject to the section 12(6) issue), such that section 12(1) applied, then the Court had and has no jurisdiction to make an order for service by alternative means pursuant to CPR 6.15.[26]That left two issues for decision, and the parties chose to argue them in the following[27]As the backdrop to both these issues, Counsel for the USA stressed his argument (based on caselaw which I discuss below) that service of legal proceedings on a foreign State is ‘a relatively unusual matter’ and that such service involves ‘particular sensibilities’ and is of ‘considerable sensitivity’ amongst States. Accordingly, it is necessary to set out these considerations first, before addressing the two specific issues.

Service under the State Immunity Act 1978

[28]On the general topic of service under the SIA, Counsel for the USA made the following submissions, which I did not understand Counsel for J&J to dispute, following his acceptance of the point mentioned at [25] above – see [33.xv)] below.[29]Although Counsel addressed me on some of the developments which led to the passing of the SIA, I can start with the observation made in the UK Supreme Court that in the mid-1970s it had become apparent that there was an urgent need for legislation in this field, and what was needed was a new statutory scheme providing detailed and comprehensive rules in cases involving foreign and Commonwealth States: Argentum Exploration v. Republic of South Africa [2025] AC 555 (“Argentum”) at [24]-[25], per Lord Lloyd-Jones JSC and Lord Hamblen JSC (with whom Lord Briggs, Lord Leggatt, and Lord Richards JSC agreed).[30]The SIA 1978 made “new provision” with respect to proceedings in the United Kingdom by or against foreign States, s. 1(1) of which confers on a foreign State a general immunity from the jurisdiction of UK courts except as provided in Part I (entitled “Proceedings in United Kingdom by or against States”): General Dynamics United Kingdom Ltd v. State of Libya[2022] AC 318 (“General Dynamics”) at [30], per Lord Lloyd-Jones JSC (with whom Lord Burrows JSC and Lady Arden JSC agreed).[31]The Supreme Court in General Dynamics at [30] further explained that the immunity of foreign States extends to both the adjudicative and enforcement jurisdiction of UK courts: viz, ss. 2-11 SIA 1978, setting out exceptions to immunity from adjudicative jurisdiction; whilst ss. 13(2)-(6) and 14(3)-(4) address and establish exceptions to the immunity from enforcement jurisdiction.[32]s. 12 SIA 1978 confers procedural privileges on foreign States in respect of service of process and judgments in default of appearance and in General Dynamics it was accepted by the parties and not contradicted by the Supreme Court that s. 12 applies both to the Court’s adjudicative and enforcement jurisdictions: see, under the heading “Issue 1: The scope and effect of section 12(1) SIA”, General Dynamics at [30].[33]The Supreme Court in General Dynamics, per Lord Lloyd-Jones JSC (with whom Lord Burrows JSC and Lady Arden JSC agreed), stated in relation to s. 12(1) SIA 1978 and the corresponding CPR 6.44: i) Considerations of international law and comity “are in play” when considering s. 12, since the SIA 1978 is primarily concerned with relations between sovereign States and, as a result, its provisions fall to be considered against the background of established principles of international law and this area is one of “considerable sensitivity” amongst States: General Dynamics at [58]-[59]. ii) The sovereign equality of States is a fundamental principle of international law and this rule is reflected in the rules of international law governing State immunity: General Dynamics at [59]. iii) Serving legal proceedings on a foreign State is “a relatively unusual matter” and there are advantages in establishing clear procedures by which it may be effected: General Dynamics at [60]. iv) As Lord Sumption explained in a different context, whilst the purpose of service is to bring the contents of the claim form to the attention of the defendant, the manner in which this is done is important; specifically, rules must identify the precise point from which time runs for the purpose of taking further steps: General Dynamics at [44]. v) An underlying rationale for s. 12 is that:
“The exercise of jurisdiction by the courts of one state over another state is an act of sovereignty. The institution of such proceedings necessarily requires that the defendant state should be given notice of the proceedings. The service of process on a state in itself involves an exercise of sovereignty and gives rise to particular sensibilities. Section 12 is intended to create a procedure whereby service may be effected on a state, in the interests of both parties and in a manner which accords with the requirements of international law and comity. These considerations suggest that a broad reading of section 12(1) is appropriate. The words ‘other document required to be served for instituting proceedings against a state’ in section 12(1) are wide enough to apply to all documents by which notice of proceedings in this jurisdiction is given to a defendant state, subject only to section 12(6). Any narrower reading would necessarily exclude certain proceedings against a state with the result that in such cases no provision would be made in the SIA for notifying a defendant state of the initiation of proceedings against it.” (General Dynamics at [43]) (emphasis added) vi) s. 12(1) provides that service of any document required to be served for instituting proceedings against a foreign State shall be served by transmission through the FCDO to the Ministry of Foreign Affairs of the foreign State: General Dynamics at [31]. vii) Service shall be deemed to have been effected when the document in question is received at the Ministry of the receiving foreign State: General Dynamics at [31] & [34]. viii) Such diplomatic service is, in the absence of any agreement on service, the “manner of service least likely to give offence” and this “process provides a means of commencing proceedings which meets the requirements of international law and comity, in the interests of both parties and the United Kingdom … In my view, section 12 SIA is founded by Parliament on these considerations of comity”: General Dynamics at [62]. ix) s. 12(1) does not prevent service of a document in any manner to which the foreign State has agreed pursuant to s. 12(6): General Dynamics at [31]. x) In relation to s. 12(1) service, the applicable procedural rules are set out at CPR 6.44-6.47, and CPR 6.44 “echoes” s. 12(1) SIA 1978: General Dynamics at [31] & [36]. The claimant must file at the Central Office of the Royal Courts of Justice a request for service to be arranged by the FCDO and a copy of the claim form or other document. The Senior Master then sends the document to the FCDO with a request that it should arrange for it to be served: General Dynamics at [31]. xi) Since such diplomatic service should be effected on the defendant foreign State by transmission to its Ministry of Foreign Affairs, it is necessary to comply with any requirements for service out of the jurisdiction pursuant to CPR 6.36-6.37: General Dynamics at [31]. Here, the Supreme Court referred to s. 12(7) SIA 1978 which provides in part that s. 12(1) “shall not be construed as affecting any rules of court whereby leave is required for the service of process outside the jurisdiction”. xii) The FCDO has no general discretion to decline to effect service. This is a matter of great importance to ensure that the executive cannot obstruct access to the Courts and thus the FCDO “is obliged” to use its best endeavours to effect service in accordance with s. 12: General Dynamics at [33]. xiii) When s. 12(1) applies, the procedure for diplomatic service is the “exclusive and mandatory method for service on a foreign State”—subject only to the possibility of service in accordance with s. 12(6) in a manner agreed by the foreign State—with the mandatory nature of s. 12(1) being “strongly support[ed]” by “considerations of international law and comity”: General Dynamics at [37], [76(2)], [76(5)] & [81]; and, e.g., The European Union (Represented by the European Investment Bank) v. The Syrian Arab Republic [2018] EWHC 181 (Comm) at [4]. xiv) Consequently, the Courts cannot dispense with such service, pursuant to CPR 6.16 or CPR 6.28, even in “exceptional circumstances”; CPR 6.1(a) makes clear that the CPR do not purport to oust the requirements of s. 12(1) SIA 1978, (where it provides that CPR Part 6 applies to the service of documents, “except where … any other enactment … makes different provision”
. As the USA submitted, the SIA 1978 is such an “enactment”, in this context) and in any event the CPR do not give the Courts a discretion to dispense with what is a statutory requirement: General Dynamics at [77]-[84]. xv) Accordingly, the Courts have no discretion to authorise service by alternative methods, in accordance with CPR 6.15, where a foreign State is concerned and s. 12(1) SIA 1978 applies: Rukundo v. Rwanda [2025] EWHC 1675 (KB) at [12].[34]I accept those points, but I must now set out some further principles, the application of which was in dispute.

Time to respond to proceedings

[35]Section 12(2) SIA 1978 provides that any time for the foreign State to enter an appearance—whether prescribed by rules of Court or otherwise—shall begin to run two months after the date on which the relevant document is received via diplomatic channels (as provided for in s. 12(1) SIA 1978).[36]Counsel for the USA submitted that this two-month period is a recognition of the fact that States, given the often-complex nature of their decision-making processes, require additional time to respond to legal proceedings: General Dynamics at [63] & [65]. It also codifies the approach set out in Article 16.4 of the European Convention on State Immunity 1972.[37]In the USA’s evidence, it was stated that the United States, as a foreign sovereign State, insists as a matter of policy on this 60-day period: see the Second Witness Statement of Gregory Bacon at [11]. Counsel also submitted that this is further reflected in the United States’ own approach to the bringing of proceedings against foreign States before the US courts; under the Foreign Sovereign Immunities Act of 1976 (the “FSIA”), foreign States are granted 60 days to respond to a complaint: 28 USC § 1608(d). In addition, as a matter of reciprocity, the United States noted that the alternative methods of service authorised by the Court via the Orders in this case (save for service pursuant to Article 5 of the HSC 1965, which is permitted, provided that a certificate of service is issued) would not be permissible under the FSIA in a patent revocation claim brought against a foreign State before a US court: see, 28 USC § 1608(a) (under which strict compliance with the requirements of the same is required and actual notice of the claim is insufficient: Transaero, Inc. v. La Fuerza Aerea Boliviana, 30 F.3d 148, 154 (D.C. Cir. 1994)).

Agreed method of service – s.12(6)

[38]Section 12(6) SIA 1978 provides an exception in the SIA 1978 to the exclusive and mandatory regime set out in s. 12(1): s. 12(6) providing that service in another manner is permitted if the State has “agreed” to the same.[39]If there is an ‘agreement’ for the purposes of s. 12(6), the claimant may serve either by the method agreed or pursuant to s. 12(1): CPR 6.44(7).[40]Those propositions were agreed. To explain the more detailed arguments made on this point I must set out the contentions made by each side.

The USA’s contentions

[41]Counsel for the USA drew attention to a number of bilateral and multilateral conventions that provide for service of, inter alia, judicial documents in legal proceedings, including the HSC 1965. He was keen to stress however, the following points, none of which I understood the Claimant to dispute: i) Within the meaning of s. 12(6) SIA 1978, ratification of such a convention alone does not amount to an ‘agreement’ by each State party to service of proceedings by the methods provided for in the convention: Andrew Dickinson and Alexander Thompson, The State Immunity Act 1978 (OUP, 2025), para. [15.43]. That this is the position is borne out by the fact that: a) s. 12 SIA 1978 makes no overt reference to such conventions, even though by the time of its enactment there were over a dozen ratifications of the HSC 1965, including by the United Kingdom: ibid. b) Although s. 17(2) SIA 1978 provides that references to an “agreement”, in s.s 2(2) and 13(3) SIA 1978, are to be read as including references to “a treaty, convention, or international agreement”, no equivalent provision is made in the SIA 1978 for s. 12(6). c) Further, and by way of analogy, a foreign State’s ratification of the New York Convention 1958 is not—in and of itself and regardless of whether the foreign State has agreed to arbitration—a submission to the adjudicative jurisdiction of the English Courts by “prior written agreement” for the purposes of s. 2(2) SIA 1978: CC/Devas (Mauritius) Ltd v. The Republic of India [2025] 1 WLR 4287 at [107]. d) It follows that service on a foreign State in accordance with the HSC 1965 is not permissible for proceedings brought against that foreign State in England, unless there is also a collateral agreement within the meaning of s. 12(6) to accept service under the HSC 1965: Andrew Dickinson and Alexander Thompson, The State Immunity Act 1978 (OUP, 2025), para. [15.42].[42]Counsel for the USA also stressed his point that assumptions against the interests of a foreign State, in this context, are not to be made lightly: ABCI v. Banque Franco-Tunisienne (Costs) [2003] 2 Lloyd’s Rep. 146 at [29]. If a foreign State wishes to proclaim to the world (for example, in domestic legislation) that it can be served in a particular way, though, this may constitute an ‘agreement’ for the purposes of s. 12(6) SIA 1978, provided that it is clearly directed at the service of foreign proceedings: ibid.[43]Other than his submissions at a relatively high level, Counsel for the USA took a series of more specific points which are best dealt with after I have explained the Claimant’s position.

The Claimant’s contentions

[44]The Claimant’s case under this head was simple: i) An AFS was filed at the UKIPO on behalf of the USA. The AFS filed was the address of a firm of patent attorneys in London, Grünecker. ii) Service of these proceedings was made to that AFS. iii) Therefore, whatever the position under s.12(7), the USA was validly served with these proceedings.[45]In a little more detail: on 19 March 2026 J&J became aware that the UKIPO had amended the AFS listed on the Patents Register, replacing the USDH’s address in the US with that of Grünecker’s London offices (“Grünecker UK”). Upon inquiry with the UKIPO, J&J were informed that the change was made following emailed requests by Grünecker on 27 February and 5 March 2026. In the letters accompanying the requests, Grünecker requested that its office “be established as address for service under the following [Grünecker UK] address”. The Claimant points out that this was done without any reservation.[46]The USA’s evidence on this application confirms that Grünecker did so pursuant to a request by the National Institutes of Health (“the NIH”) (an office within the USDH) instructing Grünecker to proceed with validating EP 383 inter alia in the UK.[47]The use of such an AFS in respect of proceedings brought in the Patents Court is governed by CPR 63.14, which provides as follows: “63.14(1) Subject to paragraph (2), Part 6 applies to service of a claim form and any document in any proceedings under this Part.(2) A claim form relating to a registered right may be served – (a) on a party who has registered the right at the address for service given for that right in the appropriate register at— (i) the United Kingdom Patent Office; provided the address is within the United Kingdom; or (b) in accordance with rule 6.33(1) or 6.33(2) on a party who has registered the right at the address for service given for that right in the appropriate register at– (i) the United Kingdom Patent Office. (a) on a party who has registered the right at the address for service given for that right in the appropriate register at— (i) the United Kingdom Patent Office; provided the address is within the United Kingdom; or (b) in accordance with rule 6.33(1) or 6.33(2) on a party who has registered the right at the address for service given for that right in the appropriate register at– (i) the United Kingdom Patent Office.

Specific points taken by the USA

[48]I deal with these in turn, but in essence these specific points were: i) A claim that the AFS was only provided for a limited purpose: to validate the Patent in the UK, with the implicit claim that the AFS was not provided for the purpose of service of any proceedings or claim concerning the Patent. ii) A claim that the provision of the AFS was done without authority.

Limited purpose?

[49]The USA argued in its evidence that provision of the AFS was “for the purposes of UK validation of a European patent” and is “an administrative requirement for that validation”. However, Counsel for the Claimant demonstrated those points were simply incorrect, not least because the EP(UK) had already been granted at the time the requests to register the AFS were made.[50]Furthermore, s.77(1) of the Patents Act 1977 is clear that there is no such administrative requirement. Instead, it provides “a European patent (UK) shall, as from the publication of the mention of its grant in the European Patent Bulletin, be treated for the purposes of Parts I and III of this Act as if it were a patent under this Act … and — (a) the proprietor of a European patent (UK) shall accordingly as respects the United Kingdom have the same rights and remedies, subject to the same conditions, as the proprietor of a patent under this Act”. The statute therefore provides for automatic rights in an EP(UK) as soon as the mention of its grant is published.[51]It is also wrong that the USA was required to provide an address for service to the UKIPO as a precondition of validation. See s 77.05 of the Manual of Patent Practice which states (emphasis added):
“The proprietors of a European patent (UK) may provide an address for service within the United Kingdom (including the Isle of Man), Gibraltar or the Channel Islands. A convenient time for proprietors to notify the Office of this address is as soon as it becomes apparent that a European patent application is going to be granted, which will usually be on receipt of the notice issued by the EPO under EPC rule 71(3). If, however, the comptroller is not notified of an address for service for the proprietor of a European patent (UK), then the proprietor’s address on the register will be treated as the address for service, even if that address is outside the UK, Gibraltar or the Channel Islands (see …below).”
[52]In practice, therefore, as the Claimant submitted, the UKIPO does not require an AFS to be provided for a European (UK) Patent. If a proprietor elects not to provide an AFS, the UKIPO treats their address as the AFS, even if they are based overseas.[53]Thus, the provision of an AFS in the UK was not obligatory and was not necessary to obtain the grant of the EP(UK). It was something that the USA elected to do. Viewed objectively, I agree that the purpose includes the use of such address in proceedings concerning the Patent as provided for under CPR 63.14.[54]Counsel for the Claimant also drew attention to Patents Form 51, the usual form by which a change to the AFS is notified to the UKIPO. That form includes a section 5 in which the applicant is required to indicate whether they have been authorised “to act in all matters relating to” the patents/applications in question, and if not to give details of the extent of their appointments. In this instance Grünecker did not use Form 51, but the Claimant stresses they were doubtless aware of the ability to limit their authority to act in certain matters that Form 51 provides for, yet did not seek to do so.[55]As already indicated, s.12(6) permits service in any manner “to which the State has agreed”. Whether a State has agreed to be served in a particular manner is a matter to be determined objectively: AELF MSN 242, LLC v De Surinaamese Luchtvaart Maatschappij[2022] EWHC 544 (Comm) (“AELF”) at [41]. S.12(6) imposes no formal requirements on the nature of the agreement and, as the Claimant submitted, it has been held that such agreement may therefore exist in any form, whether by writing and/or speech and/or conduct: Rukundo v Rwanda[2025] EWHC 1675 (KB) at [91] (Master Dagnell), referring to Williams v Federal Government of Nigeria & Anor [2023] EWHC 3282 (Comm)[56]-[61]. On this basis, I accept the Claimant’s submission that this extends to a case where a State has made a proclamation to the world that it can be served in a particular way, provided that it is clearly directed at proceedings in the courts of other States (see ABCI v. Banque Franco-Tunisienne[2002] 1 Lloyd’s Rep 511, [182]).[56]The Claimant also invited me to view this dispute in the context of what has occurred in the UPC proceedings, where the Claimant says the USA has taken tactical steps in supporting 2seventy’s infringement claim in the UPC and where it has provided an address for service for the purposes of intervening in those proceedings (see above). The USA has voluntarily chosen to be a party to infringement proceedings of the equivalent patent at the UPC and has not required any formalities of service to be complied with. It also holds a large number of UK patents for which a nominated representative, and a UK address for service, has been provided. The Claimant makes the point that Grünecker are experienced patent attorneys and would certainly have been familiar, at the time the request to amend the AFS was made, with the procedural rules governing service at the AFS – including CPR 63.14.

No authority?

[57]It was suggested in the USA’s evidence that in instructing Grünecker, the NIH did not “as a matter of US law” have authority to authorise acts that would waive the “procedural privileges and immunities of the United States”. This assertion was related in Dr Bacon’s Second Witness Statement, on instructions from Katherine J. Nesbitt, Senior Trial Counsel with the US Department of Justice, Office of Foreign Litigation.[58]Apparently, this suggestion was made on the basis that such authority could only reside in the US Department of Justice (“US DoJ”). As the Claimant submitted, it is unclear why the USA considers that US law is relevant to the question before this Court, which is a matter of English law. In any event, no evidence was adduced as to the US law said to support that proposition, nor the respective roles and authorities of the US DoJ and the NIH/USDH, beyond the mere assertion made. It is also difficult to understand how it could arise since the NIH is an office within the USDH, which is itself part of the US Government. The Claimant therefore submitted, that its act in providing, or authorising Grünecker to provide, the AFS was therefore an act of the US State, just as much as had it issued from the US DoJ. I agree.[59]Again, the Claimant points to the contradictory position in the UPC proceedings. There the USA has requested (and the UPC has ordered) that service of documents in those proceedings be made at the address of its nominated representative. That request was made on behalf of “the United States of America, including the Department of Health and Human Services, Office of Technology Transfer, National Institutes of Health … (hereinafter “United States””). That request both confirmed the NIH as being part of the USDH and in turn part of the US Government and confirmed that it had authority to “waive the procedural privileges and immunities of the United States” – insofar as agreeing to a method of service other than through diplomatic channels is said to do so.[60]Further, it has been held that s.12(6) does not require the agreement to be reached in the exercise of the State’s sovereign authority: AELFagain at [41].[61]In essence, the Claimant submitted that the USA, or Grünecker acting on its behalf, has therefore volunteered to provide an AFS, knowing that the address would be listed on the public register for any third party to see, and knowing that English procedural rules provided for service of revocation proceedings at that address.[62]For those reasons the Claimant submitted that:(i) in taking that step the USA was effectively proclaiming to the world that proceedings in respect of the Patent could be served on it in the United Kingdom at the AFS; and(ii) such declaration amounted to an agreement to service by that means under s.12(6) SIA.[63]The final point I take into account is this: there must be thousands of patents in force in the UK in respect of which an AFS in the UK has been entered on the Patents Register, without any limitation as to extent of the appointment. In these circumstances, the Court should, in my view, be extremely reluctant to entertain any attempt (after the event) to impose previously unstated limitations.[64]I should also mention a point made by Counsel for the USA in the course of submissions based on s.2(7) of the SIA. Section 2 of the SIA is concerned with submission to the jurisdiction. Relevant sub-sections provide as follows: ‘(1) A State is not immune as respects proceedings in respect of which it has submitted to the jurisdiction of the courts of the United Kingdom. (2) A State may submit after the dispute giving rise to the proceedings has arisen or by a prior written agreement; but a provision in any agreement that it is to be governed by the law of the United Kingdom is not to be regarded as a submission. … (6) A submission in respect of any proceedings extends to any appeal but not to any counter-claim unless it arises out of the same legal relationship or facts as the claim. (7) The head of a State’s diplomatic mission in the United Kingdom, or the person for the time being performing his functions, shall be deemed to have authority to submit on behalf of the State in respect of any proceedings; and any person who has entered into a contract on behalf of and with the authority of a State shall be deemed to have authority to submit on its behalf in respect of proceedings arising out of the contract. …[65]The argument presented by Counsel for the USA was that s.2(7) indicated that only the head of a State’s diplomatic mission in the United Kingdom had the authority to submit to the jurisdiction, and therefore the NIH did not have such authority.[66]This argument misses the point entirely, in my view, and I reject it. Having provided an AFS, there is no question of any submission to the jurisdiction being required. Alternatively, as s.2(2) tends to indicate, the provision of the AFS is the equivalent of a prior written agreement. Further, there is nothing (beyond unsubstantiated assertion) to suggest that only the head of a State’s diplomatic mission in the United Kingdom has the authority to provide an AFS to the UK IPO.

Conclusion on service under section 12(6)

[67]As I indicated at the conclusion of submissions, I reached the clear conclusion that service of the claim and accompanying documents had been validly effected by service at Grünecker UK. I rejected all the submissions made by the USA to the contrary.

An action in rem within s.12(7)?

[68]To reiterate, section 12(7) SIA 1978 provides that s. 12 “shall not be construed as applying to proceedings against a State by way of counter-claim or to an action in rem” (emphasis added).[69]There are, so far as Counsels’ researches went, no authorities which have decided on the scope or application of s. 12(7) SIA 1978.[70]The dispute between the parties raised two related issues: i) The first is one of construction of the phrase ‘an action in rem’ in the context of s.12 and the SIA. ii) The second is whether an action for revocation of a patent is such ‘an action in rem’.

The contentions of the USA on s.12(7)

[71]In construing a statutory provision such as s. 12(7) SIA 1978, Counsel for the USA stressed the following points: i) First, the approach to construction given by the Supreme Court to the SIA 1978 in General Dynamics at [39], per Lord Lloyd-Jones JSC (with whom Lord Burrows JSC and Lady Arden JSC agreed), that “regard [should be had] to the ordinary meaning of the statutory provision, its purpose and its legal context, including [in the case of the SIA 1978] considerations of international law and comity”. ii) Second, he reminded me from General Dynamics that the service of legal proceedings on a foreign State is “a relatively unusual matter” and that such service involves “particular sensibilities” and is of “considerable sensitivity” amongst States: General Dynamics at [43] & [58]. For this reason, there are advantages afforded by establishing clear procedures by which service of legal proceedings on a foreign State may be effected: General Dynamics at [60]. iii) The legislative purpose of s. 12 of the SIA 1978—including s. 12(7)—is to ensure that all instances of service on a foreign State in its capacity in personam—other than in a specific manner agreed to by the foreign State—should take place via diplomatic service.[72]Accordingly, Counsel for the USA submitted that the proper construction of the exception in relation to an “actionin rem” in s. 12(7) SIA 1978 is that it applies only to true proceedings against a State in rem, i.e., against a “thing” whereby service can be effected on that thing itself by affixing the claim documents to it.[73]In support of that proposition, Counsel made the following more detailed points: i) First, as a matter of English law, such proceedings in rem are limited to Admiralty claims against a ship or its cargo, and the English High Court has no jurisdiction to entertain any in rem action outside of the limits of this Admiralty jurisdiction (e.g., in respect of any general civil or commercial claim)—see, e.g.: a) ss. 20-21 of the Senior Courts Act 1981 (the “SCA 1981”), ss. 21(2)-(5) of which set out the situations in which an “action in rem” may be brought in the English High Court, i.e.: i) Against the ship or property in connection with which any such claim as is mentioned in ss. 20(a), (c), or (s) SCA 1981, or any such question as is mentioned in s. 20(2)(b) SCA 1981, arises: s. 21(2). ii) Against a ship, aircraft, or property in any case in which there is a maritime lien or other charge on that ship, aircraft, or property: s. 21(3). iii) Against a ship in the case of any such claim as is mentioned in ss. 20(e)-(r) SCA 1981: s. 21(4). iv) In the case of a claim in the nature of towage or pilotage in respect of an aircraft, against that aircraft (in certain circumstances): s. 21(5). ii) CPR 61.1(2)(c), which defines a “claim in rem” as “a claim in an admiralty action in rem brought in accordance with section 21(2) to (5) of the Senior Courts Act 1981” (emphasis added); and CPR 61.2(1)(a), stating that a “a claim … in rem” mustbe started in the Admiralty Court. Further, see the Admiralty Court, ‘FAQs’ (“… The claims which must be pursued in the Admiralty Court are listed in CPR 61.2(1). They includeany claim which is an ‘in rem’ claim … An ‘in rem’ claim is a claim which falls within section 21(2) to (5) of the Senior Courts Act 1981.” (emphasis added). iii) The Commentary to the CPR, at White Book (2026), Volume 2, para. 2D-25:
“A claim in rem may properly be issued only when the jurisdiction can be invoked by proceedings in rem under ss.21(2), (3), (4), or (5) of SCA 1981”. iv) In terms of case law: a) Republic of India v. India Steamship Co. Ltd (No. 2)[1998] AC 878 at 906-913, per Lord Steyn who addressed the true juridical nature of an “action in rem” exclusively within the Admiralty context. b) The Niyazi S [2016] 1 All ER (Comm) 843 at [12]: “[t]he action in rem is distinctive in that it enables a ship to be arrested to compel the provision of security and, if security is not forthcoming, to enable the Admiralty Court to sell the vessel free of all encumbrances to satisfy the claims against the ship… [the action in rem] is a vehicle which provides the Court with jurisdiction to deal with the res upon arrest ….”) (emphasis added). v) Dicey, Morris & Collins on the Conflict of Laws (OUP, 2025), Volume 1, para. [13-002] says this: “[t]he only claim in rem which exists in English law is an Admiralty claim brought in the Queen’s Bench Division of the High Court”
(emphasis added). vi) Interpreting s. 12(7) SIA 1978 as applying only to true proceedings in rem, i.e., Admiralty claims, is consistent with the wording of the provision itself. s. 12(7) contains two carve-outs: one for counterclaims and the other for actions in rem. However, it is only in relation to the former that the phrase “against a State” is used. By contrast, the latter makes no mention of “a State”. This signifies that, by “action in rem”, s. 12(7) has in mind only those in rem proceedings which are capable of being brought against, and served on, a “thing”, i.e., a ship (or cargo). vii) This makes perfect sense in the context of s. 12 SIA 1978 as a whole: a) Obviously, a defendant to proceedings brought before the English Courts by a foreign State should not have to serve any document required to be served for instituting a counterclaim against that same foreign State via diplomatic channels pursuant to s. 12(1) SIA 1978: by bringing the proceedings, the foreign State has submitted to the jurisdiction of the English Courts and is already participating in such proceedings before them. b) Equally, it would be nonsensical for s. 12(1) to apply to a true action in rem, such as an Admiralty claim in rem against a ship (or cargo): i) The “most important practical advantages” of such proceedings in rem are that they “confer a right of arrest” and “establish jurisdiction through service on the res within the jurisdiction” (i.e., on the “vessel named in the claim form as the vessel against which the action is brought …”); and that the action may then proceed to trial even though the owners of the vessel are out of the jurisdiction and have not been served personally with the proceedings: Argentum at [56] (emphasis added). ii) A claimant issuing such an Admiralty action in rem must be able to serve the claim against the ship in question, such as by affixing the claim documents to it, including for the purposes of arrest, without having to comply with the service requirements in s. 12 SIA 1978. Otherwise, the foreign State could simply direct that the ship leave the jurisdiction before service is effected. iii) The Supreme Court in Argentum explained that “[a]fter there has been acknowledgment of service of an action in rem, the action becomes in personam. It does not, however, lose its character of being an action in rem but continues as a hybrid action”: [57]. c) By contrast, no such justifications apply to ordinary CPR Part 7 proceedings brought against a foreign State in respect of, say, non-tangible property owned by that foreign State within the United Kingdom, such as a patent. viii) This construction of s. 12(7) is consistent, also, with the rest of SIA 1978: a) The only other references to an “action in rem”, in the SIA 1978, are in: i) s. 10, which is titled “[s]hips used for commercial purposes” and applies to Admiralty proceedings (and “proceedings on any claim which could be made the subject of Admiralty proceedings”): s. 10(1) SIA 1978. Throughout s. 10, wherever the term “action in rem” is used, it forms part of the wider expression “action in rem against a ship” (or “against a cargo”), or similar. ii) s. 13(2)(b), which provides that “the property of a State shall not be subject to any process for the enforcement of a judgment or arbitration award or, in an action in rem, for its arrest, detention or sale” (emphasis added). This further demonstrates that an “action in rem”, within the meaning of the SIA 1978, is a reference to true proceedings in rem which are capable of being brought against a ship or its cargo for its arrest, detention or sale: it would make no sense to refer to the “arrest” or “detention” of non-tangible property, such as a patent. iii) s. 17(5), which states that in relation to Scotland in Part I SIA 1978—which Part includes s. 12(7)—“action in rem” means “such an action only in relation to Admiralty proceedings” (emphasis added). This must reflect the fact that “action in rem” might ordinarily have a broader meaning in Scotland than in England (i.e., as applying, in Scotland, to any legal action based on a real, as opposed to personal, right), such that s. 17(5) serves to confine the intended scope of “action in rem” in the SIA 1978 to Admiralty proceedings against a thing—i.e., a ship (or cargo)—alone (as per ss. 10, 12(7), and 13(2)(b) SIA 1978). This approach is confirmed by, e.g., Andrew Dickinson and Alexander Thompson, The State Immunity Act 1978 (OUP, 2025), para. [20.14]:
“Section 17(5) was intended to limit references in Scots law to actions in rem in Admiralty proceedings, excluding ‘certain actions related to ownership of other property ….’”
(emphasis added). ix) That this is the correct construction of s. 12(7) SIA 1978 is supported, too, by CPR 6.44, which expressly refers, at CPR 6.44(7), to the service exception in s. 12(6) SIA 1978 (service by an “agreed” alternative method of service, other than through the FCDO), but not to the “action in rem” carve-out in s. 12(7). That must be because service in relation to true actions in rem, i.e., against ships (or cargo) in Admiralty proceedings, is dealt with elsewhere in the CPR: see, e.g., CPR 61.3; paragraph 3 of CPR Practice Direction 61 (titled “[C]laims in rem”), which provides (inter alia) that a claim form in rem must be in Form ADM1 (paragraph 3.1) and may be served “on the property against which the claim is brought by fixing a copy of the claim form … on the outside of the property in a position which may reasonably be expected to be seen” (paragraph 3.6(1)(a)). The United States observed that the position is similar in the United States: the requirements for notice on a foreign State in an Admiralty action in rem claim before the US Courts are addressed separately in the FSIA (see, 28 USC § 1605(b)), and such requirements do not apply to a claim for revocation of a patent. x) This interpretation of s. 12(7) SIA 1978 is further supported by academic commentary: see, Andrew Dickinson and Alexander Thompson, The State Immunity Act 1978 (OUP, 2025), in which the authors observe, at para. [15.44], that the fact that s. 12(7) provides that s. 12(1) SIA 1978 shall not be construed as applying to actions in rem represents a deferral to “the procedure in Admiralty proceedings whereby service of the originating process in an action in rem is effected on the res (ie the ship or cargo)”. (emphasis added)[74]I should record that the USA sought to rely in their Skeleton Argument (but not in oral argument) on statements made in the Notes on Clauses in the Bill which led to the making of the SIA. However, those statements are plainly inadmissible, as Counsel for the Claimant submitted, so I have not paid any attention to them.

The Claimant’s contentions on s.12(7)

[75]Counsel for the Claimant reminded me that the correct approach to statutory construction was summarised by Lord Hodge JSC in R(O) v Secretary State for the Home Department [2022] UKSC 3. Lord Hodge emphasised from [29] that the task for the Court is to identify the meaning borne by the words in question in the particular context. External aides to interpretation play a secondary role. I propose to apply that guidance.[76]Beyond that, the Claimant submitted simply that patent revocation proceedings are actions in rem. Counsel put forward the following points in support: i) Historically patent proceedings were commenced by petitioning the Crown to revoke the patent monopoly. It was not a requirement to serve legal proceedings on the patentee but they would be informed by registered letter (see Hoffmann J in Napp v Pfizer [1993] FSR 150, at [11]). The legal proceedings were and are directed against the property, which is the patent monopoly, and its revocation results in its removal from the register and is good against the whole world: that is why, so the Claimant submitted, it is described as an action in rem and not an action in personam. ii) With the introduction of the Rules of the Supreme Court it was necessary to serve the petition for revocation upon the respondent and with the introduction of the Civil Procedure Rules the formal distinction between petitions and claim forms was lost. But the in rem characteristic of patent revocation proceedings was not altered as a result of this procedural change. Revocation proceedings remain directed against the monopoly right and its removal from the register. iii) That that position has not changed, is affirmed by the Supreme Court in Virgin Atlantic v Zodiac[2013] UKSC 46, [2014] AC 160 (“Virgin”). In Virginthe Court considered whether the defendant, having unsuccessfully challenged the validity of a patent before the UK Court, was later estopped from relying on the subsequent revocation of the patent at the EPO on the enquiry as to damages. Lord Sumption JSC, giving the leading judgment, explained that there was no estoppel because of the in rem nature of the act of revocation by the EPO. As he explained:
“[32] …The revocation of the patent was an act in rem which determined the status of the patent as against the world. It had been revoked by the authority which had granted it and must be treated as never having existed.” iv) Lord Neuberger, in his concurring judgment, further explained that it is a characteristic of the act of revocation that it is one that takes effect against the res – i.e. the patent – and hence is binding on the world at large: “[60] Fletcher Moulton L.J. rightly said in Poulton [1908] 2 Ch 430, at p.439, that “[t]he order of revocation is in the nature of a judgment in rem which terminates the res” … He acknowledged that “[a]s regards the world at large, every one is bound by the fact that the patent ceased to exist”, and, as a matter of legal principle and consistency, as well as a matter of common sense and fairness, I consider that “every one” includes a party who has previously been held to infringe it.” v) In characterising the act of revocation in those terms, Lord Sumption and Lord Neuberger were distinguishing revocation, being an act in rem, from an act (or judgment) in personam. The reference in section 12(7) of the SIA to an “action in rem” is a reference to an action which will give rise to a judgment in rem. vi) The term “in rem” has been applied to patent revocation proceedings by the courts of other common law jurisdictions, See for example: Orikan Group Pty Ltd v. Vehicle Monitoring Systems Pty Ltd [2023] FCA 1031, at [56] and [80]; Eli Lilly Canada Inc v. Teva Canada Limited [2018] CAF 53, at [34]; Boehringer Ingelheim Pharma v. Controller of Patents; decision of the High Court of Delhi at New Delhi, 24 February 2026 at [63]-[64]. by the EPO, See T 789/89 (“improvements in or relating to relief valves for sanitation systems or the like”) Decision of the TBA of 11 January 1993 – at 2.3 (pp.8-9). and by the US Federal Court of Appeals. Regents of the University of Minnesota v. LSI Corporation, Avago Technologies U.S. Inc. (June 14 2018), Docket No. 2018-1559, Additional Views of Dyk, Wallach, and Hughes, pp. 7-8. See in particular p.7: “IPR is similarly an in rem proceeding—a proceeding to reevaluate the validity of an issued patent”. vii) There are examples of the English courts using the term “action in rem” to refer to proceedings and/or judgments that have in rem effect: a) The terminology of an “action in rem” has been applied in respect of determining jurisdiction in respect of “proceedings which have as their object rights in rem in immovable property.” under the Brussels Conventions Respectively art.24(1) of Regulation (EU) No 1215/2012 of the European Parliament and of the Council of 12 December 2012 on jurisdiction and the recognition and enforcement of judgments in civil and commercial matters (“Brussels II”); art. 22(1) of Council Regulation (EC) No 44/2001 of 22 December 2000 on jurisdiction and the recognition and enforcement of judgments in civil and commercial matters (“Brussels I”); and art.16(1) of the Convention on Jurisdiction and the Enforcement of Judgments in Civil and Commercial Matters 1968 (the “Convention”). . See the decision of the ECJ in Webb v Webb,holding thata declaration as to whether the Claimant’s son held property under trust did not constitute an action in rem because it did not claim rights “directly relating to the property which are enforceable against the world” and thus “[the] action is not an action in rem within the meaning of article 16(1) of the Convention but an action in personam.”
Webb v Webb [1994] Q.B. 696, decision of the ECJ at [14]-[15]. The term is used throughout the reasoning of AG Damon and the ECJ to refer to proceedings that “have as their principal subject matter” rights in rem. See also the opinion of AG Damon, in particular his analysis from [33] et. seq. Webb v Webb has been applied in subsequent decisions of the English Courts concerning whether proceedings “have as their object I.e. “principal subject matter”: Ashurst v Pollard [2001] Ch 595at [41]. rights in rem”, without any apparent conceptual difficulty with the ECJ’s use of the term “action in rem” to describe such proceedings. See Ashurst v Pollard [2001] Ch. 595 at [38]-[56]and Magiera v Magiera [2016] EWCA Civ 1292 at [20]-[25] and [52]-[55]. See Massey v Glover[2006] EWHC 2323 (Ch)at [17] and Prazic v Prazic[2006] EWCA Civ 497 at [13] for examples of the Court adopting the term action in rem in relation to the proceedings in question. b) See also Sidoli v Sidoli[2025] EWHC 125 At [36]-[42] (Deputy Master Dew). for a further example of the courts applying the term “action in rem” in a similar context. Namely whether a judgment of the Italian courts including declarations as to ownership of property in an estate fell within the terms of s.4(2)(b) of the Foreign Judgements (Reciprocal Enforcement) Act 1933, providing that a foreign court shall be deemed to have had jurisdiction “in the case of a judgment given in an action of which the subject matter was immovable property or in an action in rem of which the subject matter was movable property, if the property in question was at the time of the proceedings in the original court situate in the country of that court”. c) In Wolverhampton City Council & Ors v London Gypsies and Travellers & Ors[2023] UKSC 47, the Supreme Court applied the term “action in rem” to summary possession orders against trespassers under CPR r55 (upon execution of which the bailiff can remove not merely squatters present when the order was made, but also squatters who arrived on the relevant land thereafter). As the Court, in a combined judgment, explained, such actions:
“are the creature of the common law rather than equity, being a modern form of the old action in ejectment which is at its heart an action in rem rather than in personam”
. Wolverhampton City Council at [166]. See also Trinity College Cambridge v Persons Unknown [2025] EWHC 1577 (Ch)at [37]:
“The action for possession is in essence an action “in rem” enabling the claimant to obtain physical occupation of the land.”
(emphasis added). See also Manchester Airport Plc v Dutton[2000] Q.B. 133at 143 (Chadwick J) referring to an ejectment order as “an action in rem for possession of the land”. viii) What characterises these actions in rem is that they determine the status of the res itself, such that they take effect against the world at large and not only against a particular defendant. Proceedings to revoke a patent plainly fall within the common understanding of “action in rem” in that sense.[77]The Claimant sought to meet the Defendant’s point (that the reference to an “action in rem” in section 12(7) should be read as meaning an admiralty action and only an admiralty action) by making the following contentions: i) An admiralty action is a distinct species of action in rem. It falls within the scope of s.12(7) SIA, but there is no basis to read the words “admiralty action” into s.12(7). Had section 12(7) been limited to admiralty actions it would have said “admiralty actions” and not “actions in rem”. The following matters are of note: a) Admiralty actions are specifically addressed in s.10 of the SIA “Ships used for commercial purposes”. In that context, s.10(2)(a) refers to “an action in rem against a ship belonging to a State”; and s.10(4)(b) refers to “an action in rem against a cargo belonging to a State” (emphasis added). Reference is made to proceedings in relation to patents in s.7 of the SIA. It follows that where Parliament wanted to make reference to particular types of in rem proceedings it did so explicitly. No such qualifying words to “action in rem” are used in s. 12(7). b) Section 17(5) SIA provides:
“In relation to Scotland, in this part of the Act ‘action in rem’ meanssuch an action only in relation to Admiralty Proceedings”
. No such limitation is specified in relation to England and Wales. Hence in respect of England and Wales the term action in rem should be interpreted as not being so limited. In other respects, the SIA makes special provision for Scotland (see s. 13(6)), and this is just another example.[78]For these reasons, the Claimant submitted that this action fell within the exception to section 12 of the SIA provided by section 12(7) and consequently the Judge was entitled to make the orders for alternative service under the Orders.

The USA’s points on the Claimant’s contentions

[79]Counsel for the USA reiterated his point that an action in rem in s.12(7) is limited to ‘true proceedings in rem’ i.e. those brought in Admiralty proceedings.[80]By way of distinction, he argued that a patent revocation claim is not such a true action in rem, for the following reasons: i) Contrary to what was said by J&J in their Skeleton Argument in support of their Service Application at [76], it was not found in Virgin that a patent revocation claim is an actionin rem. ii) Rather, it was held that a Court’s determination on the validity of a patent is a ‘decision’, or “act”, in rem, in that it determines such validity not only as between the parties but as against the world more generally: Virgin at [7] and [32], per Lord Sumption JSC (with whom Lady Hale JSC, Lord Clarke JSC, and Lord Carnwath JSC agreed). iii) The fact that the Court’s decision on a patent’s validity has in remeffect does not transform the underlying patent revocation claim—brought against the proprietor, as opposed to the patent itself—into a true actionin rem. iv) Instead, a patent revocation claim is still an in personam action against the proprietor, initiated by naming it as the defendant. However, it is distinguishable from a claim for infringement of a patent: whilst a patent revocation claim may have an in remoutcome on its disposal, binding the world, a decision on infringement is in personam, binding only the parties: Virgin at [57], per Lord Neuberger (with whom Lady Hale JSC, Lord Clarke JSC, and Lord Carnwath JSC agreed). v) CPR 6.44(7) explicitly refers to the service exception in s. 12(6) SIA 1978 but makes no mention of the “action in rem” carve-out in s. 12(7). J&J’s answer to this, in making its Service Application, was that it “must be a drafting error” (Skeleton at [77]). That does not withstand scrutiny: CPR 6.44(7) is silent on actions in rem because service in relation to true proceedings in rem—Admiralty claims—is dealt with elsewhere in the CPR (and does not, unlike this case, involve service on a foreign State defendant).

Analysis

[81]Initially I was somewhat sceptical of the validity of the distinction embodied in the USA’s submissions of ‘true proceedings in rem’ as opposed to what one might loosely call ‘other’ actions which have effects in rem, including a claim for revocation of a patent. Furthermore, all the references (e.g. in commentary) to the effect that the only actions in rem were those brought in the Admiralty Court could be said to beg the question.[82]However, I have reached the conclusion that there is a valid distinction to be drawn in this context between, on the one hand, ‘actions in rem’ and judgments or decisions or acts which have effect in rem.

Construction

[83]I can start by identifying the clear legislative purpose of the two exclusions provided for in s.12(7). Both concern situations where service of initiating process on the State in question is not required: i) In the first situation, where a counterclaim is sought to be brought against the State in question, the reason is self-evident: the State has already submitted to the jurisdiction by bringing a claim. ii) In the second situation, the reason is different. No service is required on the State in question because proceedings are served on the res (whether it is a ship, aircraft or cargo). Once service has been effected on the res, the State in question, as the owner of the res, has the choice whether to acknowledge service, and if it does so, the proceedings become in personam against the state: see Argentum at [57].[84]Thus, section 12(7) reflects the unusual nature of the action in rem in English law: the substantive cause of action is bound up with the procedural advantages of service on the res.[85]Accordingly, I agree with the USA’s contentions and find that ‘an action in rem’ in section 12(7) of the SIA is a true action in rem (for want of a better expression) where the action is commenced by service on the res.[86]This conclusion is supported by a more detailed consideration, which serves to confirm that the provisions of the SIA and the CPR do indeed form a coherent whole (as one would hope). The point is that there is no drafting error in CPR 6.44(7), when it makes no mention of the ‘action in rem’ carve-out in s.12(7). That is because, as the USA submitted, service in relation to true actions in rem is dealt with elsewhere in the CPR: see CPR 61.3 and CPR PD 61 at [3].[87]For what it is worth, the conclusion is also supported by the academic commentary cited by the USA, as recorded in its submission at [73.x)] above.[88]In this regard, I make clear that I was not in any way dissuaded from this conclusion by J&J’s submissions based on the use of the term ‘in rem’ in various cases.[89]First, J&J relied on the ruling of the CJEU in Webb v Webb and the subsequent UK cases which discuss and apply that ruling (including Ashurst v Pollard, Massey v Glover, Prazic v Prazic and Magiera v Magiera). Although the CJEU used the term ‘action in rem’ in contradistinction to an action in personam, the ruling was in the specific context of Article 16(1) of the Brussels Convention (as it then was). That provided:
"The following courts shall have exclusive jurisdiction, regardless of domicile: (l)(a) in proceedings which have as their object rights in rem in immovable property or tenancies of immovable property, the courts of the contracting state in which the property is situated . . ."
[90]The ruling was made on a reference in proceedings in which the father sought a declaration against the son that the son held a flat in Antibes as trustee for the father. The flat had been purchased with funds provided by the father. The CJEU concluded that the father’s action was not an action in rem within the meaning of Article 16(1) of the Convention but an action in personam.[91]In that context, the Court was clearly using the term ‘action in rem’ as a shorthand for ‘proceedings which have as their object rights in rem in immovable property’. I observe that such proceedings can give rise to a decision in rem, but that does not convert the action to what I have been calling a ‘true action in rem’.[92]Second, J&J also relied on some other judgments which refer to an ‘action in rem’: i) First, Sidoli v Sidoli[2025] EWHC 125 (Deputy Master Dew), in which at [36], the Deputy Master observed:
‘…judgments concerning succession have generally been regarded by the English Courts as not being, or as being more than, merely actions in personam. A decision as to who is entitled to what from a person’s estate is a decision capable of being enforceable against the world, and so at least in part an action in rem.’ ii) From the context, it is clear that DM Dew was referring to the effect of a decision in rem. iii) Second, Wolverhampton City Council & Ors v London Gypsies and Travellers & Ors[2023] UKSC 47, where the Supreme Court applied the term “action in rem” to summary possession orders against trespassers under CPR Part 55 (upon execution of which the bailiff can remove not merely squatters present when the order was made, but also squatters who arrived on the relevant land thereafter). As the Court, in a combined judgment, explained, such actions: “are the creature of the common law rather than equity, being a modern form of the old action in ejectment which is at its heart an action in rem rather than in personam”. Wolverhampton City Council at [166]. See also Trinity College Cambridge v Persons Unknown [2025] EWHC 1577 (Ch)at [37]: “The action for possession is in essence an action “in rem” enabling the claimant to obtain physical occupation of the land.” (emphasis added). See also Manchester Airport Plc v Dutton [2000] Q.B. 133at 143 (Chadwick J) referring to an ejectment order as “an action in rem for possession of the land”. iv) Possession claims under CPR Part 55 divide into two categories: (1) where the proposed defendants are known, the action against them is in personam, however (2) where the claim is against ‘persons unknown’ it is served (CPR 55.6) ‘by attaching copies of the claim form etc…to the main door or some other part of the land’ or ‘by placing stakes in the land…and attaching copies of the claim form etc’ in either case ‘so they are clearly visible’
. Thus, an old ejectment order against persons unknown is consistent with my conclusion that a true action in rem is one where the action is commenced by service on the res.[93]Finally, there is the group of decisions on which J&J relied where it is said that the term ‘in rem’ has been applied to patent revocation proceedings by the courts of other common law jurisdictions (see [76.vi)] above): i) Orikanis not on point: the Federal Court of Australia merely referred to ‘the in rem nature of the rights conferred by the Patent’. ii) In Eli Lilly Canada, the Federal Court of Appeal said at [34] that ‘A determination of invalidity by either an English Court or the EPO is a decision in rem…’; entirely in accordance with Virgin. iii) Similarly, in Boehringer Ingelheim, the High Court of Delhi relied on the decision of the UK Supreme Court in Virgin ‘to support our conclusion that revocation acts in rem and retrospectively from the date of grant.’ Once again, that is a reference to the effect of a decision in rem. iv) The decision of the EPO Board of Appeal in T 789/89 merely refers to the fact that a patent grants rights in rem. v) The statement by the US Federal Court of Appeals in Regents of the University of Minnesota that ‘IPR (i.e. Inter Partes Review) is similarly an in rem proceeding – a proceeding to reevaluate the validity of an issued patent’ indicates nothing more than the fact that the decision may have effects in rem i.e. against the world. The factual question of whether an action for revocation is an action in rem within the meaning of section 12(7) SIA.[94]First, it is necessary to note that in a claim for revocation of a patent, there was undoubtedly a res. Originally, the Letters Patent for an invention were no different in their form to any other Letters Patent. The term ‘patent’ derives from the Latin patere - to lay open. The terms of any Letters Patent were laid open under seal, in contradistinction to letters close, for which the seal had to be broken in order to read them. So, in the old Letters Patent for an invention, a description of the invention was written out in the document beneath which the Seal was attached.[95]Although there existed prior informal lists of Letters Patent for inventions, the first register of patents was established pursuant to the Patents, Designs and Trade Marks Act 1883, section 23. Section 26(1) of that Act also abolished proceeding by writ of scire facias to repeal a patent, providing in section 26(2) for revocation by petition to the Court. It is relevant to note, however, that a writ of scire facias (literally, to make known) was not a writ in rem, it was a form of action and brought in personam. Generally, the writ was ‘founded upon some record, requiring the defendant to show cause why the plaintiff should not have the advantage of such record,’ or, in the more specific case of Letters Patent, why the patent should not be annulled and vacated.[96]Although there was a res (and I will assume for the purposes of argument that there still is a res), I do not believe that a claim for revocation of a Letters Patent was ever commenced by service on the res. Even if that was the mode of commencement prior to the 1883 Act (which I very much doubt: why wouldn’t the claim simply be brought in personam against the owner of the Letters Patent?), it is clear that commencing a claim for revocation by Petition to the Court did not entail service on the res. Instead, as Hoffmann J. related in Napp v Pfizer,service on the proprietor was not required, and the proprietor would be informed by registered letter.[97]In this context, it is very difficult to see why service on the res would have been required: usually, one would expect the Letters Patent to be held by the owner. Service or notification of the claim on the owner would suffice, with no need to serve on the res. Furthermore, there would be no need for arrest of the res or to hold the res as security: a plaintiff or claimant seeking revocation of the Letters Patent would no doubt regard them as worthless.[98]It is true (as the Supreme Court confirmed in Virgin) that a decision that a patent should be revoked has effect in rem – as against the whole world – even though, at least at the present day, it results from an action in personam against the proprietor of the patent.[99]However, all these considerations clearly support the conclusion I stated above. There is a valid distinction between an action in rem and a decision in rem. They are not the same. Furthermore, the fact that an action, if successful, results in a decision in rem, does not convert that action into an action in rem.

Conclusion on service under section 12(7)

[100]Accordingly, a claim for revocation of a patent is not ‘an action in rem’ within the meaning of section 12(7) of the State Immunity Act 1978.[101]It also follows that s.12(1) of the SIA applied at the time of the Orders made by HHJ Hacon. Furthermore, it also follows, as was submitted on behalf of the USA, that the Claimant’s evidence and submissions to the effect that serving the United States pursuant to s. 12 SIA 1978 would involve lengthy delays, are irrelevant. So, too, are its purported justifications for the alternative service methods in respect of which J&J requested—and was given—the Court’s permission, and its arguments in relation to prejudice. The Court had—and has—no discretion to grant permission to serve the Statements of Case on the United States by alternative methods, pursuant to CPR 6.15 (as Counsel for the Claimant accepted, as recorded above).[102]Therefore, it follows from my findings that HHJ Hacon did not have power to make orders for alternative service.[103]I should point out that I have not decided on the correctness of the statement made in Dicey, Morris & Collins cited in [73.v)] above, and leave that to a case where it is necessary to decide it.

The outstanding application for expedition

[104]The Claimant has an application outstanding for expedition of the trial of this claim. During the hearing, I provisionally indicated that the Claimant could pencil in a trial in March 2027 (which was the earliest date which I understood the Patents Court diary could accommodate), but the application for expedition will be heard alongside the consequentials hearing from this Judgment, which is to be listed as soon as possible and in any event before the end of July.

order

i) First, whether an action for revocation of a UK patent is ‘an action in rem’ within the meaning of section 12(7) of the SIA. This issue turns on an issue of statutory construction of that phrase in the context of s.12(7) and the remainder of the SIA. ii) Second, whether service at the address for service (‘AFS’) on the UKIPO Register constituted ‘service of a writ or other document in any manner to which the State has agreed’ in s.12(6), a provision which disapplies s.12(1).