IP Report
Patent Law

Entitlement to priority under the European Patent Convention Decisions
G1/22 and G2/22 of the Enlarged Board of Appeal of the European Patent
Office dated October 10, 2023
Reported by Dr. Niels Malkomes and Dr. Georg Anetsberger
With its decisions G1/22 and G2/22,
the Enlarged Board of Appeal ofthe European Patent Office (EPO)
not only settled the question which
jurisdiction and which law is applicable for assessing whether a party
is entitled to claim priority underArticle 87(1) EPC in favor of theEPO’s competence and the autonomous law of the EPC. The EBoA
moreover circumvented the disputed
concept of the “PCT joint applicantsapproach” in favor of the even moregeneric approach that there is arebuttable presumption under theautonomous law of the EPC that theapplicant claiming priority in accordance with the formal requirements
as stipulated by Article 88(1) EPC
and the corresponding Implementing Regulations is entitled toclaim priority.
1. Summary of Facts andSubmissions
The decision G1/22 concerns opposition
appeal proceedings re European patent
EP 1 755 674, whereas the decision G2/22
concerns appeal proceedings re a divisional application of the opposed patent’spatent family. Both appeal cases wereconsolidated pursuant to Art. 10(2) RPBA.
The European patent application underlying the opposed patent was published asinternational application WO 2005/110481
with the filing date of May 16, 2005 (the“PCT application”) and claims the priorityof the US provisional patent application
No. 60/571,444, filed on May 14, 2004
(the “priority application”). The priority
application was filed in the name of threeinventors. The PCT application names
the three inventors as inventors and asapplicants for the United States of America(US) only. For all designated States except
the US, it names Alexion Pharmaceuticals,Inc. and the University of Western Ontario
as applicants. The opposed patent wasgranted on November 19, 2014. Since theUniversity of Western Ontario assigned
their right to the patent application toAlexion Pharmaceuticals, Inc. in 2007, theopposed patent names the latter as the solepatent proprietor (the “patent proprietor”,
later the “appellant”).
The opposed patent was revoked after
opposition proceedings, as the priority
claim was found invalid because only thepriority right of one of the three inventors
had been assigned to the patent proprietor(the applicant at that time). As a consequence, the opposition division found thatthe subject matter of claim 1 of the main
request lacked novelty over D20 and D21
which were published after the priority
date but before the filing date.

Dr. Niels Malkomes
German and European Patent
Attorney, UPC Representative,
PartnerDr. Georg Anetsberger
German and European Patent
Attorney, UPC Representative,
Partner

BARDEHLE PAGENBERG
Partnerschaft mbB
Patentanwälte RechtsanwältePrinzregentenplatz 781675 München

Regarding the divisional application, thesame issues concerning the formal priority
were invoked during the examination proceedings, so that the divisional application
was refused because D20 and D21 were
found to be novelty-destroying prior art.

T +49.(0)89.928 05-0
F +49.(0)89.928 05-444
info@bardehle.dewww.bardehle.com
ISO 9001 certified

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Patent Law

The proprietor and the applicant,respectively, filed appeals (ex-parteappeal T 2719/19 and inter partes appeal
T 1513/17) allocated to the same board ofappeal. In both cases, the appellant argued
that the priority right derived from the priority application was valid and documents
D20 and D21 were thus not prior art.
The proprietor in particular argued thatthe so-called “joint applicants approach”
should similarly apply to PCT applications having different applicants fordifferent designated states (hereinafter,
this approach is referred to as “PCT jointapplicants approach”). The “normal”“joint applicants approach” (cf. T 1933/12)
in general relates to the scenario where aparty A is applicant for the priority application and parties A and B are applicants forthe later application. As found to be undisputed in the referring decision, party B canbenefit from the priority right to which its
co-applicant A is entitled and a separatetransfer of the priority right to party B is
not needed.
2. The Appeal Proceedings and thereferring Decisionreferring BoA noted that the jurisdictionof the EPO to decide on the entitlement
to the priority right had been extensively
addressed and supported in T 844/18,
whereas the opposite position was taken
in certain communications of boards incases that were eventually resolved without
a decision on the issue of entitlement topriority.
Consequently, the referring BoA referred
the following questions to the EBoA for
decision:I.
Does the EPC confer jurisdiction on theEPO to determine whether a party validly
claims to be a successor in title as referred
to in Article 87(1)(b) EPC?
II.
If question I is answered to the affirmative,
can a party B validly rely on the priority
right claimed in a PCT-application for thepurpose of claiming priority rights underArticle 87(1) EPC in the case where

The referring BoA decided, in accordancewith the requests of all parties, to refer“a question concerning the PCT joint
applicants approach” (referred question IIbelow) to the EBoA.

1) a PCT-application designates party A
as applicant for the US only and party B
as applicant for other designated States,
including regional European patent
protection andIn view of the parties’ position that thequestions to the EBoA should include aquestion regarding the jurisdiction of theEPO to decide on the entitlement to the priority right, the referring BoA also soughta final decision on the “jurisdiction issue”.
To justify the referral of that question, the2) the PCT-application claims priority
from an earlier patent application thatdesignates party A as the applicant and3) the priority claimed in the PCT-application is in compliance with Article 4 ofthe Paris Convention?

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3. The Decision of the Enlarged
Board of Appeal
The situation prior to G1/22
and G2/22
The EBoA considered the case law to be
substantially uniform (at least during
the past 10 or 15 years when there was asignificant increase in cases where the entitlement to priority was challenged) insofar
as the EPO is viewed to have jurisdiction todecide who is entitled to claim priority.
However, the EBoA considered the case law
to be diverging or has not developed muchin many aspects when it comes to the question how the EPO should decide disputes
on entitlement.
According to consistent case law, nationallaw is applicable to the succession in title
addressed in Article 87(1) EPC (see e.g.
T 1201/14, Reasons, point 3.1.2, withfurther references) (cf. point 62).
As the EPC does not contain conflict of law
rules for the determination of the applicable national law except for the provisionin Article 60(1) EPC that for employee
inventions the right to a European patentshall be determined in accordance withthe law of the state in which the employee
is mainly employed or in accordance withthe law of the state in which the employer
has the place of business to which theemployee is attached, there exist a variety
different options, none of which had a clear
preference in the EPO case law so far:“lex originis” (law of the country wherethe first application was filed), “lex lociprotectionis” (law of the country where thesubsequent application was filed),“lex loci contractus” (law of the country
which is agreed upon in the relevant contract), “lex domicilii” (law of the country
where at least one of the parties to thetransfer has its residence).
The respective national law was applied by
the Boards of Appeal in cases where theapplicable national law was determined.
Parties were regularly requested to fileevidence (such as a legal opinion from anindependent law expert) concerning theeffects of the applicable national laws (seealready J 19/87, Facts and Submissions,point VIII).
National courts applied conflict of law
rules, such that for instance the German
Federal Court of Justice (cf. X ZR 14/17 –Drahtloses Kommunikationsnetz, point 71)
ruled that the validity of the transfer ofa right to claim priority for a European
patent application is subject to the lawsof the state of the priority application(lex originis).
The referring BoA considered that it was“far from clear” that the legal requirement for the transfer of priority rights
by agreement should be assessed undernational law, as the EPC does not contain any conflict of laws rules (referringdecision, Reasons, point 37). The referring
BoA moreover drew the conclusion fromearlier case law that the EPC did not seemto impose any formal requirements for thetransfer of priority rights by agreement.
Rather, the referring BoA suggested therationale that an implicit agreement could
be sufficient to bring about the transferof the priority right for the EPC territory(cf. Reasons, points 38, 67).
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Regarding the question of different
applicants of the priority application andthe subsequent application, the EBoA
discusses not only the “joint applicants
approach” but also the “all applicants
approach” used, for example, in decision T 844/18 (Facts and Submissions,point VIII). In the latter case, four
inventors were applicants of the priority
application and only three of them filed thesubsequent PCT application (encompassingthe European application) and claimed
priority. The priority claim failed to meetthe requirement of the “all applicants
approach”, i.e., that all applicants of thepriority application must also be applicantsof the subsequent PCT application forwhich the priority is claimed.
The rationale of the EBoA
The EBoA argued that priority rights areautonomous rights under the EPC andshould be assessed only in the context
of the EPC, regardless of any nationallaws, since the creation, the existence
and the effects of the priority right aregoverned only by the EPC (and by theParis Convention through its relationship with the EPC) (cf. Reasons of thedecision, point 85). Moreover, in viewof Article 87(1) EPC, the EPO has toassess all aspects of the right of priority(“where”, “what”, “when” on the one handand “who” on the other; T 844/18,Reasons, points 12 to 20) without
distinction (cf. point 91).
The priority right has to be strictly distinguished from the applicant’s entitlement
to the application. For the latter, the EPO
does not have competence, in line with
Art. 60(3) EPC (cf. point 79).

The EBoA further considered that the EPO
should adapt itself to the lowest standards
established under national laws and accept
informal or even tacit transfers of priority
rights under almost any circumstances.
The EBoA even considered, as a sidenote,that the well-known requirement thatthe transfer of the right of priority needs
to be concluded before the filing of thesubsequent European patent applicationis questionable (see point 100). According
to the EBoA, the latter is however of little
practical relevance, as the EBoA relies on
the presumption that priority entitlement
is presumed to exist on the date on whichpriority is claimed for the subsequent
European application (see point 100).
Based thereon, the EBoA further developed
the rationale of the „Rebuttable presumption of entitlement to claim priority“: entitlement to priority should in principle bepresumed to exist to the benefit of the subsequent applicant of the European patentapplication if the applicant claims priority
in accordance with Article 88(1) EPC andthe corresponding Implementing Regulations. Said rationale particularly considers
that fulfilling the formal requirements –including, inter alia, the filing of the usually
still unpublished priority application in time
– is usually impossible without the cooperation of the priority applicant. Overall, saidrationale of the EBoA takes into account(i) that the priority applicant or its legal
predecessor must under normal circumstances be presumed to accept thesubsequent applicant’s reliance on thepriority right,(ii) the lack of formal requirements forthe transfer of priority rights and4

IP Report
Patent Law(iii) the necessary cooperation of thepriority applicant with the subsequent
applicant to allow the latter to rely on
the priority right.
The EBoA considered that said approach
applies to any case in which the subsequent
applicant is not identical with the priority
applicant but receives the support of thepriority applicant required under Article
88(1) EPC. Neither does it matter whether
the subsequent European application
stems from a PCT application nor it isrelevant whether and to which extent themembers of a plurality of co-applicants forthe priority application overlap with thegroup of co-applicants for the subsequent
application (cf. point 107).
The decision emphasizes that like the priority entitlement in general, the presumption of its existence and the rebuttal of thispresumption is subject to the autonomous
law of the EPC only and that there isconsequently no leeway for the applicationof national laws on legal presumptions andtheir rebuttal (cf. point 111).
Order
In view of the above, the EBoA decided thatthe questions of law referred to the EBoA are
answered as follows (cf. also the headnote):I.
The European Patent Office is competent toassess whether a party is entitled to claim
priority under Article 87(1) EPC.
There is a rebuttable presumption under
the autonomous law of the EPC that theapplicant claiming priority in accordancewith Article 88(1) EPC and the corresponding Implementing Regulations isentitled to claim priority.
II.
The rebuttable presumption also applies insituations where the European patent application derives from a PCT application and/or where the priority applicant(s) are not
identical with the subsequent applicant(s).
In a situation where a PCT application is
jointly filed by parties A and B, (i) designating party A as applicant for one or moredesignated States and party B as applicant
for one or more other designated States,and (ii) claiming priority from an earlier
patent application designating party A
as the applicant, the joint filing implies
an agreement between parties A and B
allowing party B to rely on the priority,
unless there are substantial factual indications to the contrary.

Remarks

Particularly US applicants seeking protection for their inventions by EP patents,
in particular via PCT applications, will berelieved by the rebuttable presumption oflegal validity of the entitlement to claim

priority established in G1/22 and G2/22.
Up until the relevant provisions of theAmerica Invents Act came into effectin 2012, US patent applications had tobe filed with the inventors as applicants.

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Particularly European patents claiming
priority to these applications will continue
to be in force for another decade, and thesepatents will greatly benefit from the EBoA'srebuttable presumption.
Point 110 of the decisions of the EBoA
leaves no doubts that the typical approachof challenging the validity of the entitlement to priority by throwing doubts
and pleading ignorance that the formal
requirements – whereof at least some of
the crucial facts are typically solely within
the sphere of the applicant and hardly publicly available – were actually met is not
sufficient. Rather, the party challenging theentitlement to priority must demonstratethat specific facts support serious doubts
about the subsequent applicant’s entitlement to priority.
The fact that the presumption of entitlement exists on the date on which thepriority is claimed which may date backsome considerable amount of time does notmake the opponent’s life easier either.
The EBoA however points out that, eventhough the rebuttable presumption in favorof the priority entitlement is subject tothe autonomous law of the EPC, nationallaws may still need to be considered (seepoint 133). As an example, the EBoA
mentions that the existence of legal entities
being parties in transfers of priority rights
may be relevant and may need an assessment under national laws.
Thus, even though challenging the validityof the entitlement to priority has become
more difficult for third parties, some points
of attack still remain. Nevertheless, thetypical opponent’s strategy applied before

G1/22 and G2/22 will require substantialrefinement.
Other possible points of attack mentionedby the EBoA are bad faith behavior of thesubsequent applicant or the outcome ofother proceedings such as litigation before
national courts about the title to the subsequent application (cf. point 108).
Notably, the rebuttable presumption ofentitlement to claim priority also applies to
EP patent applications and patents that arecited in proceedings before the EPO and thatclaim a priority, such that it may be easier toestablish these documents to be prior art.
The EBoA considered that the presumptionof entitlement exists on the date on which thepriority is claimed (and thus not on the dateon which the subsequent application is filed).
According to Rule 52 of the implementing
regulations of the EPC, the declaration may
still be made within sixteen months fromthe earliest priority date claimed and thus
even after filing the subsequent application.
Insofar, it does not seem to be entirely clear
whether the EBoA even gave up the hitherto
well-known principle that the transfer ofthe right of priority needs to be concluded
before the filing of the subsequent European
patent application. Notably, the EBoA states
at another place in the decisions and in linewith EPO case law (T 1201/14, Reasons,point 3.1.1.1; T 577/11, Reasons, point 6.5,
Catchword 3; T 1946/21, Reasons, point 2.3)
that (cf. point 68) the “requirement that theright of priority has to be transferred before
the filing of the subsequent application
can be described as a requirement basedon autonomous substantive law under
the EPC”, deduced from the wording ofArt. 87(1) EPC.

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