Ensuring Valid Priority Rights in Europe
Richard Johnson - Mewburn Ellis LLP
I.
Introduction
Article 4A of the Paris Convention confers a right of priority to “any person … or his successor
in title” who has duly filed an application in a Paris Convention member state. The right of
priority is referred to herein as an “entitlement to priority”. This paper discusses this subject in a
European context in the situation where the applicant(s) for the earlier application is/are different
from the applicant(s) for the later application.
This issue is of current interest for two reasons. Firstly, current case law suggests that a missing
entitlement to priority cannot be fixed after the event, which means steps must be taken during
the priority year to ensure that entitlement to priority exists for all countries in which the
application will ultimately be pursued. Secondly, third parties have successfully raised the issue
of priority entitlement in court proceedings in the UK and France to invalidate a patent.
Entitlement to priority is not finally decided during prosecution.
II.
Different applicants – how can the right transfer?
This paper discusses three situations in which the applicant(s) of the earlier application is/are
different from the applicant(s) of the later application. Those situations can be represented as
follows:
Priority application applicant(s)
A
A+B
A
→
→
→
→
Later application applicant(s)
B
A
A+B
The A → B situation (i.e. where there are no common applicant entities between the priority
application and the later application) is common. For example, a US provisional application is
filed in the name of the inventor or inventors, whereas a subsequent PCT application claiming its
priority may be filed in the name of a company (e.g. for all designated states except US).
Alternatively, an initial application is filed in the name of the inventor, who goes on to establish
a company in the priority year, and all subsequent applications are filed in the name of the
company.
The A + B → A situation (i.e. where the later applicant is in the name of one of the original
applicants but not one (or more) of the other applicants) is more unusual, but might occur e.g. in
the UK if A was a company and B was an inventor not employed by the company and no formal
agreement about the ownership of the invention was reached until after the first application was
filed.
The A → A + B situation (i.e. where the later application has one or more additional applicants)
may occur if a business partner becomes involved after the first application is filed.
How can the right to claim priority be transferred in these situations? A number of possibilities
spring to mind, including:
(a)
(b)
(c)
(d)
through a specific assignment,
by virtue of employment by at the priority date,
by the conduct of the parties,
through a general agreement made before the invention was conceived.
One area of uncertainty that has arisen in Europe following a number of recent cases in the area
(see below) is which of the above applies in any given situation. One might think that the law
governing the transfer of the right is determined based on the identity of the applicants. For
example, if a PCT patent application is filed in the name a US company claiming priority to a US
provisional application filed in the name of a US inventor, one might assume that the transfer of
priority right might be assessed under US law. However, as explained below, the most recent
case law on this issue from the Boards of Appeal of the European Patent Office, and the UK and
French courts indicates that this is not necessarily how this assessment is made.
III.
Case law review
A.
European Patent Office
1.
T62/05
At the European Patent Office, the current position of the Boards of Appeal vis-à-vis the A → B
situation is indicated in decision T62/051.
Decision T62/05 concerned a European patent application filed in the name of General Electric
Company and claiming priority to a Japanese patent application filed in the name of Nihon GE
Plastics K.K. The Board acknowledged that the European Patent Convention does not contain
any formal requirement to be fulfilled by an assignment of the right to claim priority. However,
they reasoned that in light of “the crucial effect a valid priority date has on patentability” it was
reasonable to apply “an equally standard of proof as the one required for the assignment of an
European Patent application by Article 72 EPC, i.e. that the assignment of priority rights has to
be in writing and has to be signed by or on behalf of the Parties to the transaction”.
The appellant in decision T62/05 could not produce a document that satisfied this requirement.
The Board did not accept arguments that the transfer had taken place implicitly or that the action
the parties based on their established filing policy had in effect caused the transfer to occur.
This decision is notable for the reason that no consideration appeared to be given to the law
governing the relationship between the parties. For example, no consideration was given to
whether the parties established filing policy served as an actual assignment under the national
law of either applicant. The (implicit) formal requirements of the EPC were held to be all
important.
1
T 62/05 (unpublished) GE Plastics Japan K.K./Polycarbonate resin composition
2
This decision actually represents a departure by the Boards of Appeal from earlier case law. In
decision T1008/962 the Board held that “the succession in title must be proven to the satisfaction
of the board. It is a general principal of procedural law that any party claiming a right must be
able to show that it is entitled to that right (see decision J 19/873). It is true that this question is
to be answered in accordance with national law.” In decision T1008/96 the Board was
confronted with contradictory evidence concerning the ownership of two Italian utility models,
which were the priority applications for the European patent application in question. On the one
hand there was a document issued by an Italian court after the filing date of the European patent
application which indicated that the inventor was the owner of the priority applications. On the
other hand there was a declaration from the earlier applicant that there had been an agreement to
transfer the right of priority. In their decision the Board gave more weight to the document from
the Italian court and found that there was no valid priority claim.
Decisions T1008/96 and J19/87 where not referred to in decision T62/05, so no reason has been
given for the change in direction of jurisprudence. On the face of it, there are now therefore two
conflicting strands of Boards of Appeal case law, one which requires the existence of a formal
agreement fulfilling the EPC’s formal criteria for a legal transfer, and one in which the national
law governing agreements between the parties is used to determine whether or not a transfer has
in fact taken place. This state of affairs is in principle enough to warrant a referral to the
Enlarged Board of Appeal for a definitive decision. Whether or not that happens will probably
depend on whether or not T62/05 is followed in future cases. T62/05 was cited with approval in
decision T382/074, where an assignment document was produced late in the appeal proceedings
that was held to confirm that the right of priority had been properly transferred. Decision
T1008/96 has not been cited in the context of assessing the validity of a priority claim.
Given the strict approach taken in T62/05, more challenges to the validity of the priority claim
can be expected in future oppositions, so it is likely that this issue will come before other Boards
of Appeal in due course.
2.
T788/05
The current position of the Boards of Appeal vis-à-vis the A + B → A situation can be derived
from decision T788/055. At issue in this decision was the effect of the juxtaposition of the terms
“a person” and “first application” in Article 87(1) EPC6. In this case, a first application had been
filed jointly by Terumo and Tokin. A second, later, application was filed by Terumo only. The
later European patent application that was the subject of this appeal claimed priority from the
second (Terumo-only) application. The opponent sought to demonstrate that the priority claim
2
T 1008/96 (unpublished) Giat S.r.L./Improved gasket of elastomer material in the form of a closed or open frame for cooking
oven door
3 J 19/87 (unpublished) Burr-Brown Corporation/Apparatus and methods for analogue-to-digital and digital-to-analogue
conversion
4 T 382/07 (unpublished) D & W Trading B.V./ Pharmaceutical compositions, based on etheric oils obtained from plants for use
in the human and veterinary medical field
5 T 788/05 (unpublished) Terumo Kabushiki Kaisha/Vascular catheter
6 Article 87(1) EPC corresponds to Article 4A of the Paris Convention, and states: “A person who has duly filed an application
for a patent ..., or his successors ... in title, shall enjoy, for the purpose of filing a European patent application in respect of the
same invention, a right of priority during a period of twelve months from the date of filing of the first application.”
3
was invalid because the second application was not the “first application” and hence did not
satisfy the requirements of Article 87(1) EPC.
No evidence of a transfer of the right of priority for the first application was put before the
Board. The Board stated that “the priority right belongs simultaneously and jointly to the two
applicants, who thus constitute a legal unity unless one of them decides to transfer his right to the
other applicant”. Thus, in the absence of an agreement transferring the right of priority, the first
application could not be a valid priority claim to an application filed by Terumo only.
B.
United Kingdom
1.
Edwards Lifesciences AG v Cook Biotech Inc.
The A + B → A situation (i.e. where one of the applicant entities for the priority application is
not also named on the later application) corresponds to the situation examined by the UK High
Court in Edwards Lifesciences AG v Cook Biotech Inc7. Here, a first application was filed in the
name of three joint inventors, only one of whom was an employee of Cook. A PCT application
was filed claiming priority from the first application. The PCT application named Cook as the
sole applicant for all states except the US. However, an assignment of rights from the other
inventors to Cook was made only after the PCT application was filed.
The judge agreed that the rights belonging to the inventor who was an employee of Cook did
automatically transfer to Cook. The court did not perform a detailed analysis of the legal
mechanism behind this transfer. The judge was happy to accept that the interest in a US
employee’s invention vested in his US employer. There was no discussion about which
country’s law was applicable. Possibly this was because the outcome (which was not disputed)
would have been the same if the relevant provisions of the UK Patents Act 1977 had been
applied.
Accordingly, Cook was held to own a “share” of the right of priority belonging to the employee
inventor. However, this was not enough to save Cook, because the judge held that the right of
priority belonged jointly to the three inventors and as such could only be exercised jointly. Since
there had not been a transfer of the other shares to Cook when the claim to priority was made,
there was no valid priority claim.
The judge in Edwards Lifesciences AG v Cook Biotech Inc indicated that his decision was
consistent with the case law of the Boards of Appeal of the European Patent Office, in particular
decision T 788/05.
In this case, the loss of priority was significant because there was an intermediate publication (a
journal article published between the priority date and the PCT filing date) which anticipated the
patent. The case was appealed, but on appeal the priority issue was not re-examined. The
appeal judges focussed instead on a prior art publication that predated the priority date and held
that the patent was obvious from that publication. There was thus no need to reconsider the
priority entitlement issue.
7
Edwards Lifesciences AG v Cook Biotech Incorporated [2009] EWHC 1304 (Pat)
4
An important aspect in Edwards Lifesciences AG v Cook Biotech Inc is that the priority
entitlement, unlike the entitlement to the patent itself, could not be corrected after the PCT
application had been filed. It is essential to have the right of priority in your possession at the
time of making the claim to priority.
2.
KCI Licensing Inc v Smith & Nephew plc
The A → A + B situation (i.e. where one or more additional applicant entities are named on the
later application) was considered in KCI Licensing Inc v Smith & Nephew plc8. In fact, this case
was slightly more complicated even than that, because the later application did not share any
applicants with the first application. The priority application (a US provisional application) was
actually filed in the name of the inventor (A), whereas the PCT application which gave rise to the
European patent at issue was filed in the name of a first company (A') for all designated states
except the US and naming an additional second company (A'') of GB only.
The inventor was employed by the first company. It was submitted that the right of priority
transferred to the first company either by virtue of a confidentiality agreement that was entered
into by the inventor “in consideration of employment” with the first company or by virtue of a
specific assignment signed shortly after the first application was filed.
The confidentiality agreement included the following term: “I hereby assign and agree to assign
to the Company all right, title and interest in all confidential information, inventions and
improvements conceived or developed by me, alone or in conjunction with others, during my
employment and for a period of three (3) years after termination for whatever reason, which
relate to any phase of the Company's business.” The judge decided that this term was effective
to transfer the priority right, even though at the time of signing the agreement the invention at
issue had not been conceived.
The confidentiality agreement stated that it was governed by the law of the State of Texas. No
evidence on how the agreement should be interpreted under Texas law was presented to the
judge, and an interpretation according to English law was accepted by all parties. However, this
indicates that the UK court would consider the impact of an agreement under the national law of
another country if it were applicable to the transfer of the right of priority.
When considering the specific assignment, the judge in this case decided that is was more
probable than not that an assignment had taken place, despite the fact that no document was
produced for the court.
The other interesting point in this case was the effect of adding the second applicant (A'') for GB
only. The judge reasoned firstly that the point was moot because the GB designation was
different from the EP(GB) designation from which the European patent derived. However, the
judge also stated that even if he was wrong on this point, adding a second applicant would not
adversely effect a priority claim because it can be inferred from the conduct of the first applicant
when filing the subsequent application that it “had agreed by conduct to transfer part of its
8
KCI Licensing Inc & others v Smith & Nephew plc & others [2010] EWHC 1487 (Pat)
5
interest in the invention” to the co-applicant. The judge accepted that no greater degree of
formality was required.
In light of the formal approach taken in decision T 62/05, it is not clear that the European Patent
Office would decide this case in the same way. In contrast to the insistence on formality seen in
T62/05 (and in the French case discussed below), the judge here stated that “when determining
whether a person is a “successor in title” for the purposes of the provisions, it must be the
substantive rights of that person, and not his compliance with legal formalities, that matter”. One
argument put forward and rejected in KCI Licensing Inc v Smith & Nephew plc was to apply the
reasoning of T 788/05 in reverse, i.e. the entity that filed the first application must be identical
(no more, no less) to the entity that claims priority. Applying this argument in combination with
T62/05 leads one to the uncomfortable position that a priority claim may not be valid where coapplicants are added to the later application in the absence of a formal written agreement. This
position has not yet been tested at the EPO.
C.
France
A recent decision of the French Tribunal de Grande Instance9 examined the situation in which a
PCT application filed in the name of a company (A') claimed priority to a US provisional
application filed in the name of three inventors (A, B and C). The inventors had signed a transfer
document for all rights deriving from the US provisional for the US before the PCT application
was filed.
According to existing French case law, the right of priority exists as an independent right; it does
not automatically transfer with other rights in the priority application. Thus, under French law,
the right of priority only transfers if it is expressly mentioned in a transfer agreement. In this
case, the transfer document did not mention the right of priority for subsequent applications in
other jurisdictions, so the court held that there was no valid priority claim.
One of the more controversial aspects of this case is that the inventors and company were all
resident in Switzerland, and the French court was provided with strong evidence that according
to Swiss national law the transfer document was a valid assignment of the right of priority. So,
in a similar manner to the EPO, the French court has decided that the right to priority is to be
determined according to local law (the law of the country in which the patent is ultimately
effective). However, they have applied a different test (express mention of transferring the right
of priority) to the EPO (assignment document in writing and signed by both parties).
D.
Germany
In a recent decision from the German Bundespatentgericht10, it was confirmed that the right of
priority in Germany is an independent, freely-transferable right. Moreover, it was held that a
valid priority can arise if the right of priority is transferred before the formal transfer of the other
rights to the invention. However, in the same way as in Edwards Lifesciences AG v Cook
Biotech Inc., discussed above, it is essential for right of priority to be transferred before the
9
TGI Paris, 30 January 2009 - Magic Technologies v Swisscom AG
11 W (pat) 14/09 (full decision not yet published at time of writing)
10
6
subsequent application is filed. An important point of the decision is that the transfer of priority
should take place “at least the day before the declaration of priority” is made.
IV.
Summary of the current position
The diagram below illustrates the various situations where there is a change in the number of
applicant entities between a priority application and a subsequent application claiming priority.
The dotted lines indicate a relationship between the parties (e.g. assignment, agreement, conduct)
through which the right to claim priority passes.
Fig. 1 corresponds to the Edwards Lifesciences AG v Cook Biotech Inc situation, where the first
application was filed in the name of the inventors (A, B and C here), and there was a transfer of
the right of priority from one of the inventors (A) to a company (A'), but no transfer of the right
of priority (and no evidence of any agreement to do so) from the other original applicants (B and
C) to the company applicant A'.
Fig. 2 corresponds to the situation where an agreement to transfer the right of priority from
original applicants A, B and C to subsequent applicant A' exists when the subsequent application
is filed.
Fig. 3 corresponds to a situation similar to that in KCI Licensing Inc v Smith & Nephew plc,
where the subsequent application names two additional co-applicants (B and C), but there is no
evidence of an agreement to transfer a share of the priority right to them before the subsequent
application is filed.
Fig. 4 represents a situation in which there is evidence that the right of priority belonging to the
original applicant (A) was transferred to all subsequent co-applicants jointly before the
subsequent application is filed.
Fig. 1
A
B
C
Legend:
Fig. 2
A'
C
A
B
C
- applicant entity
Fig. 3
A'
A
- priority claim
Fig. 4
A'
B
C
A
A'
B
C
- transfer of right to claim priority
For each situation, let us consider what legal documentation (if any) is necessary to demonstrate
the transfer of priority right such that a valid priority claim (if possible) is obtained for each of
the EPO, the UK, France and Germany.
A.
Fig. 1
7
1.
EPO
A valid priority claim probably cannot be obtained in this situation. Based on T62/05, the EPO
would look for a formal written document signed by all parties (A, B, and C) which caused the
right of priority to transfer to the company A' before the subsequent application was filed. Thus,
the transfer from A to A' would not be enough to obtain a valid priority claim at the EPO, even if
the transfer from A to A' fulfilled the formal requirements of Article 72 EPC.
2.
United Kingdom
A valid priority claim cannot be obtained in this situation. This situation corresponds exactly to
that in Edwards Lifesciences AG v Cook Biotech Inc, so we know that no valid priority claim can
be obtained unless the shares of the right to priority belonging to B and C are transferred to A'
before the subsequent application is filed.
3.
France
A valid priority claim probably cannot be obtained in this situation. The recent French case law
looks for an express transfer of the right of priority. There is no evidence of such an express
transfer of the share of the right of priority from B and C to A'.
4.
Germany
A valid priority claim probably cannot be obtained in this situation. Whilst German case law
does not necessarily prescribe an express transfer of the right of priority in the same way as
France and the EPO, it nevertheless acknowledges that the right of priority is a transferable right,
and so in the absence of evidence of a transfer from B and C to A', it appears unlikely that a valid
priority claim can be obtained.
B.
Fig. 2
1.
EPO
A valid priority claim can be obtained in this situation, but only if the evidence meets the formal
requirements set out by T62/05. According to decision T62/05, the transfer of the right of
priority must be in writing and signed by all parties to be effective. It now seems that this is the
case regardless of the legal situation in any other jurisdiction which may govern agreements
between the parties. That is, even if the evidence is enough to demonstrate that the transfer is
effective under, say, US law, the EPO will consider the priority claim invalid unless the evidence
of transfer meets the minimum EPO formal requirements.
Moreover, it is not clear from current EPO case law that there is a derogation from this formal
requirement for the transfer of rights between employee and employer. There is no guarantee
that evidence of an employee/employer relationship would be enough to effect the transfer.
2.
United Kingdom
8
A valid priority claim can be obtained in this situation. Following the assessment carried out in
Edwards Lifesciences AG v Cook Biotech Inc and KCI Licensing Inc v Smith & Nephew plc, it is
likely that the English court would consider whether the evidence of the transfer was enough to
effect the transfer of the right of priority in the country governing agreements between the
parties. As set out in KCI Licensing Inc v Smith & Nephew plc, the court would look at the
substantive rights of the applicant and would probably take into account the provisions of the
national law that applies.
Thus, if the evidence indicates that an agreement was done before the later application was filed
and was held to be sufficient to transfer substantively the right of priority, a valid priority claim
would exist. Whilst it has not yet been tested, the case law in the UK does not yet prohibit a
valid priority claim in a situation where no written agreement exists. However, one would think
that the decision in such a case would depend strongly on the effect of national law governing
unwritten agreements between the parties.
3.
France
A valid priority claim can be obtained in this situation, but only if the evidence meets the formal
requirements of the French case law, i.e. an express transfer. Based on the strict approach
adopted by the French court in the decision discussed above, it is likely that an express transfer
needs to be physical, i.e. written. Again, similarly to the EPO position, evidence that the transfer
is effective in another jurisdiction (particularly a jurisdiction in which the parties are resident) is
unlikely to succeed.
4.
Germany
A valid priority claim can be obtained in this situation, but only if the evidence indicates that a
transfer of the right of priority has taken place before (at least one day before) the subsequent
application is filed.
C.
Fig. 3
1.
EPO
A valid priority claim probably cannot be obtained in this situation, although in fact this area is
still uncertain because there is no case law that addresses this specific scenario. The situation in
Fig. 3 is the opposite of that in decision T 788/05. However, applying the reasoning in reverse
leads to the consider that the person claiming priority (A' + B + C jointly in Fig. 3) must be the
same as, or successor in title to, the person filing the first application. Here there is evidence that
A' is the successor in title to A, but no evidence that B and C have any share in that title, so one
is drawn to the uncomfortable conclusion that the priority claim is invalid.
According to decision T62/05, the evidence of transfer from A to A' must be in writing and
signed by both parties to be effective. However, even if those formal requirements where
9
fulfilled, it would not seem to cure the missing link between original applicant A and subsequent
applicants B and C.
Given the EPO’s insistence on complying with formalities in T62/05, one could infer that the
rationale for accepting a valid priority claim outlined by the UK High Court in KCI Licensing Inc
v Smith & Nephew plc would not be followed.
2.
United Kingdom
A valid priority claim probably can be obtained in this situation, following the rationale outlined
in the KCI Licensing Inc v Smith & Nephew plc case. The UK court has held that the mere
action of naming co-applicants in addition to an applicant who is fully entitled to the right of
priority is enough to demonstrate an agreement to share that right.
3.
France
It is uncertain whether or not a valid priority claim could be obtained in this situation, since this
specific situation has not been tested in the French courts. Clearly, there is no evidence of an
express transfer of the share of the right of priority from A to B and C. However, it is not clear
whether or not the explicit fact of the subsequent application being made by a plurality of coapplicants is in itself express evidence of the right of priority being shared by the applicant A'.
4.
Germany
It is uncertain whether or not a valid priority claim could be obtained in this situation, since this
specific situation has not been tested in the German courts. On the one hand the German case
allows the right of priority to be transferred before the formal transfer of the other rights to the
invention, which suggests that a decision to file the application jointly might in fact be enough to
effect the transfer. On the other hand, the German case law states that the transfer must occur at
least a day before the application is filed, so the action of naming co-applicants in addition to an
applicant who is fully entitled to the right of priority may not be enough in itself to cause the
right to be transferred validly. This latter point suggests a slight inconsistency between the
approaches of the UK and German courts.
D.
Fig. 4
1.
EPO
A valid priority claim can be obtained in this situation, but only if the evidence meets the formal
requirements set out by T62/05. According to decision T62/05, the transfer of the right of
priority must be in writing and signed by all parties to be effective.
2.
United Kingdom
10
A valid priority claim can be obtained in this situation, if the evidence indicates that an
agreement was done before the later application was filed and was held to be sufficient to
transfer substantively the right of priority.
3.
France
A valid priority claim can be obtained in this situation, but only if the evidence shows that the
right of priority was expressly transferred to the subsequent co-applicants.
4.
Germany
A valid priority claim can be obtained in this situation, but only if the evidence shows that the
right of priority was transferred at least one day before the subsequent application was filed.
V.
Practical considerations
From a practical point of view, it is desirable to ensure that the right to claim priority is correctly
vested in the applicant(s) for the subsequent application at the time that application is filed. As
shown above, there are apparently different requirements for establishing whether or not a
subsequent applicant is a “successor in title”, depending on which office or court is making the
determination. As a consequence, one may need to consider the requirements for a valid transfer
of priority right for all countries in which the patent may ultimately be pursued before the end of
the priority year. No small task in many cases!
In view of the case law discussed above, the cases which warrant care in this situation are where
there is no clear relationship between one or more of the original applicants and one or more of
the subsequent applicants at the time of filing the priority application. This may be relevant to
simple one-to-one cases, e.g. where a start up company is incorporated after the priority
application is filed. It is certainly relevant to the many-to-one case, where a priority application
with joint applicants is to go forward in the name of only one applicant. In such cases, it seems
advisable to either:
(a) obtain a written assignment transferring the right to claim priority signed by all
parties before (at least one day before) the subsequent application is filed, or
(b) file the subsequent application in the same names as the priority application and
attend to the necessary transfer of ownership and record after filing.
As mentioned above, where the priority application applicants are all employees of a company in
whose name the subsequent application is to proceed, there is an argument that the right to claim
priority may transfer automatically in accordance with national law or at least together with any
assignment of the inventor’s interest in the invention. However, in light of the recent European
Patent Office and French case law, it is risky to rely on such provisions. It is advisable to have
an express (i.e. written) agreement in place which transfers the right of priority before the
application claiming priority is filed.
11
One area that has not been explored at all in the case law is where the priority claim is added to
the subsequent application after filing. Rule 26bis.1 PCT (and Rule 52(2) EPC) permits a valid
priority claim to be made at any time up to 16 months from the priority date. Could this
provision be used to buy more time to fix an uncertain priority situation? For example, what
would be the status of the priority claim in the following scenario: (i) first application filed by A,
(ii) a PCT filed by B without any priority claim, (iii) right of priority to first application assigned
in writing to B after filing of PCT application, (iv) priority claim to first application added to the
PCT application after the agreement in (iii). One may argue that at the time the priority claim
was actually formally made, the right were formally in place. However, in this author’s view
such an argument is unlikely to succeed. The provisions governing the addition of priority
claims after filing (which ultimately derive from the Patent Law Treaty) relate to procedural
rather than substantive conditions. The substantive right of priority set out by Article 87(1) EPC
(corresponding to Article 4A of the Paris Convention) explicitly refers to a time period of twelve
months. The recent case law indicates that the right of priority must be in place and exercised
within that period to be valid.
VI.
Entitlement to the invention and patent
The discussions above have focussed on entitlement to a right of priority to an earlier
application. Whilst this right is in principle separate from the right of ownership of an invention,
i.e. the right to be granted a patent for that invention, it is advisable to consider all of this rights
together, since case law demonstrates that a patent may be lost if the chain of title in any of these
rights is defective.
One aspect yet to be explored by the Boards of Appeal at the EPO is whether or not an employer
is “the successor in title” to the right to claim priority from an application made in the name of
an employee merely by the virtue of employing the employee. Strictly applying the reasoning of
decision T 62/05 would indicate that a separate written assignment signed by both parties is
essential. But since T 62/05 was not concerned with the employee/employer situation, it may not
reach that far.
Indeed, since Article 60 EPC states that the right to a European patent made by an employee
inventor is determined “in accordance with the law of the State in which the employee is mainly
employed”, it may be possible to use the reasoning of T 62/05, which drew a parallel with
Article 72 EPC for the transfer of rights in a non-employer/employee situation, to argue that a
parallel with Article 60 EPC should be drawn whether the transfer of the right to claim priority is
between employee and employer.
However, until a decision on this point is taken, it is important to establish a paper trail of
properly executed and legally effective documents that establish an applicant’s chain of title to
(1) the right of priority to a first application, and (2) the right to have the patent granted to them.
As discussed above, for the purposes of the right of priority, the applicant ideally needs evidence
that, at the date of filing a subsequent application claiming priority, they own the right of priority
to the first application. This may be evidence that they own all of the rights in the first
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application, or (especially in the light of recent French case law) evidence that expressly
indicates that the right of priority to the first application is owned by them.
For the purposes of the right to grant of the patent, the patent applicant needs evidence that they
own the whole of the invention. For most jurisdictions, this assessment is made at the date of
grant, but for some jurisdictions it is assessed at the date of filing the application.
Clearly, the value of a patent will be greatly reduced if defects in the patentee’s chain of title
mean that it may not be enforceable. Such defects cannot necessarily be cured later, since certain
dates are critical and in most jurisdictions it is not possible to backdate an assignment. The chain
of title may have to be defended at any point during the patent’s lifetime, and in the courts of any
country covered by the patent rights. Moreover, commercial interests may re-align during the
lifetime of a patent in ways that the parties would not have imagined at the outset. Through a
sequence of assignments, mergers and acquisitions, invention and patent rights that have started
out in the hands of research partners can sometimes ended up in the portfolios of competitors.
Potential investors into any company whose value resides largely in its intellectual property carry
out rigorous “due diligence” exercises in relation to its patent portfolio, and these usually involve
scrutiny of the company’s title to each item in that portfolio and a demand for warranties that the
company owns all its claimed intellectual property rights. Thus, the importance of establishing
proper entitlement without doubt becomes ever more desirable.
VII.
Conclusion
Recent case law indicates that ensuring valid priority claims in Europe requires action to be
taken during the priority year and with an eye on the formal requirements of the countries in
which the patent is ultimately to be effective. Especially in cases where there is not complete
identity between the applicant of the first application and the applicant for subsequent
application, it is highly advisable to obtain a written assignment of the right of priority signed by
all parties.
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