This appeal decision relates to a discussion of insufficiency of disclosure in opposition proceedings. In this opposition proceedings, all requests were rejected because it was not well defined how the claimed "viscosity" could be determined. The Board also discusses this subject with reference to previous case law. Furthermore, in the appeal the patent proprietor tried to argue that viscosity was not an important feature of the claim, however, contradictory arguments were provided earlier and statements in the patent application seems to contradict the new line or arguments.
Citations from the decision:
Catchwords:
An ill-defined parameter in a claim may lead to
insufficiency of disclosure if this parameter is relevant for solving
the problem addressed in the patent (T 593/09 followed). If, in such a
situation, the patent specification states that the ill-defined
parameter is relevant and the patent proprietor initially argued along
those lines, then, normally it cannot argue, later on in the
proceedings, that this parameter does not matter (points 2.6.1 and 2.6.2
of the Reasons).
[...]
The opposition division's position can be summarised as follows:
None
of the requests met the requirements of Article 100(b) EPC. It had not
been substantiated that there was a particular method in the prior art
which had to be used to determine the viscosity. The skilled person was
therefore faced with a number of choices as to which procedure to use,
choices which influenced the outcome of the measurement. While claim 1
specified which temperature had to be employed, further conditions such
as the selection of the viscosimeter, as well as the container used and
the sample pre-treatment, had to be selected and there was no
unambiguous instruction on these choices. In fact, given that D10
(section 11 "Report") specified that these conditions had to be
controlled, the skilled person would infer that these conditions had an
appreciable effect on the measurement. It also appeared from D10 that
the spindle/speed combination had a major bearing on the outcome of the
measurement. This was further demonstrated by the proprietor itself in
its letter of 8 August 2011, which showed large differences in the
measured viscosity at different spindle speeds. It could therefore only
be concluded that it had not been proven that the skilled person knew
which method to use, and, within a single method, the number of
selections required inevitably led to different results. Reproducing the
invention thus required a significant effort which went beyond any
normal trial and error. As the viscosity was an essential parameter in
practising or reproducing the invention, without proper instruction on
this parameter the skilled person was not able to perform the invention.
Reasons for the Decision
[...]
2. Sufficiency of disclosure (Article 100(b) EPC)
2.1
Claim 1 is directed to a composition for coating foodstuffs which
comprises a galactomannan, such as guar gum, and 2 to 7 wt% of alginate,
and has a viscosity of 80-110 Pas at a temperature of 20°C (for the
exact wording of claim 1, see point IV above).
According to the
respondent, the viscosity parameter in claim 1 is ambiguous since the
patent does not give the method for identifying it, and this ambiguity
means that the invention underlying the patent is insufficiently
disclosed.
2.2 The present case is similar to the one underlying
decision T 593/09 (not published in OJ EPO), in which sufficiency of
disclosure had likewise to be decided in relation to a parameter ("LTC
temperature") for which the measurement method was not sufficiently
defined in the patent. As set out in this decision (catchword and point
4.1.4 of the Reasons), the ambiguity of a parameter in a claim is not,
by itself, a reason to deny sufficiency of disclosure. What is decisive
for establishing insufficiency within the meaning of Article 83 EPC is
whether the parameter, in the specific case, is so ill-defined that the
skilled person is not able, on the basis of the disclosure as a whole
and using his common general knowledge, to identify without undue burden
the technical measures necessary to solve the problem underlying the
patent.
As set out in this decision, in order to find out whether
this condition for insufficiency of disclosure is met, a four-step
approach can be applied. Firstly, the problem to be solved by the
invention in the patent is identified (point 2.1 of the Reasons),
secondly the relevance of the attacked parameter for solving this
problem is determined (point 2.2 of the Reasons), thirdly it is analysed
whether the parameter in the claim is indeed ambiguous (points 3.1 to 3.5 of the Reasons) and fourthly, if the parameter is ambiguous, it is
determined whether due to this ambiguity and the relevance of the
parameter for solving the problem, sufficiency of disclosure has to be
denied (points 3.6 and 3.7 of the Reasons). This four-step approach will
be applied in the present case as well (points 2.3 to 2.6 below).
2.3
The opposed patent relates to compositions for coating foodstuffs
(paragraph [0001]). The objective of the invention underlying the patent
is the provision of a coating composition with which a sufficiently
robust and stable coating can be formed using the extrusion or
co-extrusion techniques that are commonly used in the food industry
(paragraph [0013]).
2.4 As set out in paragraph [0004], the
rheological properties, and especially the viscosity, of the coating
composition play a major role in achieving the objective of the opposed
patent. If the viscosity is too low, the composition deliquesces before
it can be gelled, so that no cohesive coating can be formed. Too high a
viscosity can lead to problems in extrusion and to undesirable ripping
of the coating. To achieve this objective, the coating composition must
have a viscosity of 80-110 Pas at a temperature of 20°C (claim 1 and
paragraph [0029]).
The skilled person who wants to carry out the
invention, i.e. to obtain coating compositions with which a sufficiently
robust and stable coating can be formed, thus needs to determine the
viscosity of the coating composition in order to check whether it is
within the required range.
2.5 It needs to be examined, as a next step, whether the viscosity is indeed ambiguous.
2.5.1
In this respect, it was acknowledged by the appellant that the patent
does not contain any information as regards the type of measurement
device or measurement parameters to determine the viscosity, that there
are various measurement methods available to the skilled person and that
the measured viscosity values depend on the type of measurement device
and, for a given device, on the measurement parameters.
2.5.2 The
appellant argued however that the skilled person was nevertheless able
to find out which method and parameters to use in order to determine the
required viscosity. All that the skilled person needed to do was to
calibrate the measurement characteristics on the basis of the examples
of the opposed patent. More specifically, the skilled person had simply
to prepare the compositions of these examples and then to "tune" the
measurement parameters until the viscosity values reported in these
examples were obtained. The appellant in this respect referred to D12
and D13, where two independent test institutes had reworked the examples
of the patent (D12: examples 1 to 4, D13: examples 1 to 3 and 5) and,
by tuning the measurement frequency, had been able to obtain the
reported viscosity values. The measurement method thus found could be
used to check whether the viscosity of any other given coating
composition was as required in claim 1. By doing so, compositions
suitable to provide robust and stable coatings could be obtained.
Firstly,
however, it is nowhere shown in D12 or D13 that the compositions
prepared therein are indeed suitable to prepare robust and stable
coatings. In fact, it is explicitly stated by the authors of D12 that
"[F]urther work described in the patent concerning the application of
the gels to be used as a coating of sausages was not part of the
investigations [of D12]".
Secondly, it was necessary in the tests
reported in D12 and D13 to experiment with various measurement devices
that are typical for university departments specialised in viscosity
measurement and only a sophisticated multi-step analysis in the end led
to viscosity values that were at least close to those in the examples.
Such a calibration could thus only be done by a person specialised in
the field of viscosity measurement. The patent is however not directed
at an analytical scientist specialised in viscosity measurement but to
food technologists (paragraph [0001]: "The invention relates to a
composition for coating foodstuffs..."). Hence, the skilled person in
the art relevant to the patent would not be able to use the calibration
techniques applied in D12 or D13.
Thirdly, in fact a calibration
of the viscosity measurement is, as a matter of principle, not possible
on the basis of the examples of the patent. Such a calibration
presupposes that the measurement parameters are the only variables in
the examples that determine the viscosity. As will be shown in the
following, this condition is not met:
All examples of the patent
use guar gum without specifying the type of guar gum. As evidenced by
D14, D15 and D16, different guar gums are available. As shown in D17
(table on last page), the viscosity of the compositions used in the
examples depend on the type of guar gum. More specifically, in D17, the
viscosities of three mixtures each containing a different guar gum are
determined, namely containing (i) alginate and Guar HV (a guar gum
having a viscosity of 6500 ctp) (test 1), (ii) alginate and Guar
standard (3500 ctp) (test 2) and (iii) alginate and depolymerised Guar
(50 ctp) (test 3). The viscosity of these mixtures was 1360 Pas for
mixture (i), 497.5 Pas for mixture (ii) and 185.6 Pas for mixture (iii),
and thus depends on the type of guar gum used. Consequently, the fact
that the authors of D12 and D13 were able to tune the measurement method
such that the viscosities reported in the corresponding examples were
obtained does not mean that it is this method that is to be used
according to the patent. On the contrary, it could equally be a
different method, if a different guar gum was used in the examples.
For
these reasons, the appellant's argument that the measurement method for
the determination of the viscosity can be calibrated and thus
identified on the basis of the examples of the patent must fail.
2.5.3
As regards the dependence of the viscosity on the type of guar gum
shown in D17, the appellant's expert Mr Knoch argued that he had doubts
about the correctness of these values, since no details were given in
D17 about how the experiments had been carried out. This submission can
however not be taken into account in view of the fact that it was made
at the latest possible time during the appeal proceedings, while the
report had already been available for two years and furthermore since
the doubts raised by the expert were not substantiated. Irrespective of
this, even if there were some doubt about the absolute values reported
in D17, this test report shows at least qualitatively a dependence of
the viscosity on the type of guar gum.
2.5.4 The appellant also
argued that the skilled person would use a standard guard gum in the
examples of the patent and that this standard guar gum had a viscosity
between 3000 and 5000 cps, as evidenced by D14. The skilled person would
thus know which type of guar gum to use and therefore would be able to
calibrate the viscosity measurement method on the basis of the examples.
The
board does not find this argument convincing. First of all, nowhere
does the patent indicate that indeed standard guar gum is used in the
examples. Secondly, even if, in the appellant's favour, it is assumed
that the skilled person reading the examples of the patent would indeed
use standard guar gum, it would still not be possible to use the
examples to calibrate the viscosity measurement method. More
specifically, as acknowledged by the appellant, standard guar gum is
available within a viscosity range of 3000 to 5000 cps. Thus, the type
of the guar gum would still be a variable in the examples that would
affect the viscosity of the resulting coating composition.
2.5.5
Consequently, on the basis of the patent and his common general
knowledge, the skilled person is unable to identify the measurement
method by which the viscosity values required by claim 1 have to be
determined. In view of the fact that the values depend on the type of
measurement method and parameters, the skilled person cannot tell
whether or not a given composition has a viscosity as required by claim
1. The viscosity in claim 1 is thus ambiguous.
2.6 In view of its
ambiguity, the viscosity is not available as a selection criterion to
identify suitable coating compositions that solve the problem underlying
the opposed patent. The skilled person therefore has to identify
suitable compositions by trial and error. Hence, the patent is nothing
more than an invitation to perform a research programme.
2.6.1
While the appellant during the oral proceedings initially acknowledged
that the viscosity as required by claim 1 was indeed essential to solve
the problem underlying the patent, it later on presented a second line
of argument starting from the assumption that the viscosity was in fact
not relevant. According to this line of argument, all that was needed to
carry out the invention was to select the preferred galactomannan,
namely guar gum, in the amounts indicated in the description of the
patent. For instance, the skilled person simply needed to repeat the
examples of the opposed patent and choose a standard guar gum to obtain a
suitable coating composition. Hence, in order to carry out the
invention the skilled person did not need to know how to determine the
viscosity. In fact the viscosity had only been included in claim 1 to
determine later on whether a given composition infringed the patent or
not.
2.6.2 The board does not find this argument acceptable. The
proprietor is not free to choose a particular approach when drafting the
patent and when arguing its case, and then to change it later on when
it realises that this approach might fail. So if the proprietor (and in
the present case appellant) chooses to include a statement when drafting
the patent that, in order to solve the problem underlying the patent,
the coating composition must have a certain viscosity, then normally it
cannot argue, later on in the proceedings, that in fact the viscosity
does not matter.
Furthermore, even if one accepts the appellant's
argument, the patent does not teach the skilled person how to obtain a
suitable coating for any composition different from those of the
examples, for instance a composition containing a galactomannan
different from guar gum. Since, due to its ambiguity, the viscosity is
not available as a selection criterion to identify suitable components
and amounts for these different compositions, the conclusion remains
valid that the skilled person has to rely on trial and error such that
the patent is nothing more than an invitation to perform a research
programme.
[...]
2.8 The invention underlying claim 1 is thus insufficiently disclosed.
Order
For these reasons it is decided that:
The appeal is dismissed.
This decision has European Case Law Identifier: ECLI:EP:BA:2014:T240311.20140430.
The whole decision can be found here.
The file wrapper can be found here.
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