This is a revocation appeal.
The independent claims of the main request (patent as granted) read:
1. Crystalline compound of formula:
having a crystal habit such that the ratio between the length and the width of the crystals is between 1:1 and 10:1 and the chargeability of which, measured by tribogeneration, ranges between 0 and -10 nanocoulombs/g.4. Process for preparing a compound according to any one of Claims 1 to 3, characterized in that a crystalline suspension of a compound of formula (I) is subjected to at least one sonication episode and at least one temperature oscillation episode.5. Process for preparing a compound according to any one of Claims 1 to 3, characterized in that a crystalline suspension of irbesartan of acicular habit form A is subjected to at least one sonication episode and at least one temperature oscillation episode.28. Pharmaceutical composition containing a compound according to any one of Claims 1 to 3 and pharmaceutically acceptable excipients.
In what follows, Board 3.3.01 examines whether this subject-matter was sufficiently disclosed:
*** Translation of the French original ***
[2.1] The [opponents] were of the opinion that the patent in suit did not provide the skilled person with all the information necessary for measuring the following parameters in a precise and repeatable way:
- ratio between the length and the width of the crystals; and
- the chargeability measured by tribogeneration.
On the one hand, the patent does not define what the length and the width of the three-dimensional crystal structure stand for.
Moreover, document D16 shows that the chargeability values measured by tribogeneration depend on the measurement conditions. Whereas a value of -6.20 nC/g is obtained in a plastic box, -9.73 nC/g are measured on the same sample when a metal box is used. The patent in suit does not provide sufficiently precise measurement conditions […] nor does it cite the chargeability values obtained for the compounds of the examples.
These two parameters are the only features used by the [patent proprietor] for delimiting the subject-matter of claim 1 of the main request with respect to the prior art. The [opponents] concluded that in view of decision T 593/09 the grounds pursuant to A 100(b) make it impossible to maintain the patent.
[2.2] The catchword of decision T 593/09 (which has been distributed by [opponent 1] during the oral proceedings before the Board) stipulates that where a claim contains an ill-defined parameter and where, as a consequence, the skilled person would not know whether he was working within or outside of the scope of the claim, this, by itself, is not a reason to deny sufficiency of disclosure. Nor is such a lack of clear definition necessarily a matter for objection under A 84 only. What is decisive for establishing insufficiency is whether the parameter, in the specific case, is so ill-defined that the skilled person is not able to identify in the patent as a whole the technical measures necessary to solve the problem facing [the skilled person] (cf. point [4.1.4] of the Reasons)
Ratio between the length and the width of the crystals
[2.3.1] The patent in suit does not explicitly disclose how this parameter is to be determined […]. The [opponents] submitted that the length and the width of the crystal were not defined because a crystal has a three-dimensional shape. However, the [patent proprietor] has argued that it was clear for the skilled person that this ratio had been determined using a microscope producing a two-dimensional image of the crystals.
[2.3.2] The size of the crystals that is explicitly disclosed in the patent in suit is indicated as follows:
Average length: 30 μm
Average width: 5 μm
In view of these dimensions, it is clear that a microscope is used for determining the ratio between the length and the width of the crystals. What is seen with a microscope is a two-dimensional projection of the crystals; consequently, it is the side of greatest length of the crystal that defines its length and the other side defines its width.
[2.3.3] As a consequence, the skilled person does not encounter any difficulty when establishing a definition for the length and the width of the crystals. This conclusion is in line with […] the impugned decision (which also refers to documents D5 and D6).
The patent, therefore, describes how to determine the ratio between the length and the width of the crystals in a manner that is sufficient for the skilled person.
Chargeability measured by tribogeneration
[2.4.1] The patent in suit discloses the following method for measuring the chargeability:
“The chargeability of the powder is measured by tribogeneration: the powder is subjected to a strong vibration during which it becomes charged on itself, and is then transferred into a Faraday cage connected to a very sensitive electrometer.” […]
[2.4.2] As explained above (point [2.1]), document D16 shows that the chargeability depends on the material of the container in which the sample is subjected to a strong vibration. As the definition of this parameter in the patent does not mention this material, the parameter is ill-defined.
[2.4.3] According to decision T 593/09 it, therefore, remains to be examined whether this ill-defined parameter hinders the skilled person from identifying in the patent as a whole the measures necessary to solve the problem (cf. point [2.2]).
Regardless of the problem to be solved, it is necessary to prepare the compound as defined in claim 1.
As a consequence, it is decisive for the sufficiency of disclosure of the invention to determine whether the skilled person can prepare this compound although one parameter is ill-defined.
The preparation of the compound implies “that a crystalline suspension of a compound of formula (I) is subjected to at least one sonication episode and at least one temperature oscillation episode” […].
This means that the measures to be taken for solving the problem facing the skilled person are the sonication and temperature oscillation episodes […].
The sonication effect is disclosed in […] the patent in suit as follows:
“It appears that the sonication episode limits the growth according to the length of the needles by breaking them and modifies the nature of the crystal surfaces such that the zones capable of accumulating the electrostatic charges are reduced.” […]
It follows from this paragraph that this treatment results in a reduction of the chargeability of the crystals.
If this treatment, which is disclosed in the patent in suit, allows the skilled person to prepare the compound according to claim 1 without undue inventive effort, then the patent discloses the invention in a sufficient manner.
It is true indeed that the examples of the patent in suit do not indicate the chargeability of the products obtained, but this does not mean that these products do not have the required chargeability.
In an inter partes appeal each party has the duty of proving the facts which it invokes. If the [opponents] were of the opinion that the products of the examples of the patent in suit did not have the required chargeability, it was up to them to prove it, which they have not done.
[2.4.4] It should be noted that in the case underlying appeal T 593/09 the parameter that was ill-defined was a certain crystallisation temperature of a starting substance and that the Board has considered that this temperature was essential for solving the problem facing [the skilled person] (see point [2.3] of the Reasons). The Board was of the opinion that because of this deficient definition the skilled person trying to carry out the invention had no guidance for determining how to choose the starting substance without having to determine in each case whether the product solved the problem with which he was faced (see point [3.6] of the Reasons). Thus the parameter under consideration was essential for preparing the product.
In the present case, the reduced chargeability is an advantageous property of the product obtained with the process disclosed in the patent in suit […]. The vague definition of the chargeability affects the clarity of the subject-matter of the claims but does not hinder the skilled person from preparing the claimed product.
A lack of clarity is not a ground for opposition pursuant to A 100 and cannot be objected to the maintenance of the patent as such if it was already present in the claim as granted, as is the case for the present main request. However, such a lack of clarity can be taken into account when the subject-matter of such a claim is examined as to its novelty and inventive step.
[2.5] As a consequence, the reasons invoked based on A 100(b) are not sufficient for establishing that the patent cannot be maintained on the basis of the main request.
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