T 0027/14 06-03-2018

1. Consideration of documents filed for the first time in appeal proceedings

1.1 Documents D25 to D29 and exhibits A and B

Together with its statement setting out the grounds of appeal, the appellant submitted documents D25 to D29 and exhibits A and B, the admission or not of which is governed by Article 12(4) RPBA.

These documents were filed in response to the reasoning in the impugned decision. Hence, the board does not see any reason for holding documents D25 to D29 and exhibits A and B as being inadmissible pursuant to Article 12(4) RPBA.

1.2 Documents D30, D36 and D37

These documents have been submitted by the appellant (D36) and respondent 2 (D30, D37) in reaction to the respective submissions.

None of the parties objected to the admission of these documents into the proceedings and the board itself also has no concern against taking these documents into consideration.

The board therefore admits these documents into the proceedings pursuant to Article 13(1) and (3) RPBA.

1.3 Documents D31 to D35

These documents were submitted one month before the oral proceedings by respondent 1. D31 concerns a judgment of a UK court on the validity of D32, a case having a priority date from 1992; the purpose of these documents was to show the common general knowledge of the skilled person in 1992. However, common general knowledge develops over time, and it cannot be concluded that these documents are relevant for establishing the common general knowledge of the skilled person at the priority date of the contested patent in 2007.

Documents D33 to D35 are scientific articles and an expert opinion concerning XRD measurements and texture coefficients. In combination with D31, which itself makes already reference to various expert opinions, these documents, presented at a late stage in the appeal proceedings, increase the complexity of the case to such an extent that the board and the other parties could not be reasonably expected to deal with them at the oral proceedings.

By exercising its discretion pursuant to Article 13(1) and (3) RPBA the board therefore does not admit documents D31 to D35 into the proceedings.

2. Procedural defects of the opposition proceedings

2.1 Admission of documents D22 and D23 into the opposition proceedings

Documents D22 and D23 were filed by respondent 2 after the opposition period two months before the oral proceedings in opposition proceedings and therefore were late filed documents.

The minutes of the oral proceedings before the opposition division do not mention any discussion or decision on the admission of these late filed documents into the proceedings, nevertheless they are cited and taken into account in the impugned decision (see points 1.2 and 2.2 of the Reasons for the decision).

Therefore it has to be concluded that the appellant, then patent proprietor, did not get an opportunity to discuss the admission of documents D22 and D23 into the proceedings before the decision on their admission was taken, contrary to the requirements stipulated by Article 113(1) EPC.

2.2 Request for adjournment of the oral proceedings

A new objection concerning sufficiency of disclosure was raised during oral proceedings by the opposition division which arose from their assessment of D21, which had actually been submitted by the appellant in a different context; see minutes (first paragraph):

"Then the chairman made clear to the parties that document D21, filed by the proprietor, called into question the sufficiency of disclosure of the patent, the proceedings will therefore start with discussion on opposition ground under Article 100(b) EPC. The first examiner explained what the problem was."

According to the minutes, a break of 15 minutes was given to the parties to prepare any additional arguments after which the appellant requested an adjournment of the oral proceedings "to file new information documents" to support its arguments (see minutes, fourth paragraph). The opposition division refused the adjournment of the oral proceedings.

The board considers that in the present case the refusal of the adjournment constitutes an unfair treatment of the appellant since the appellant did not have an appropriate opportunity during the oral proceedings to prepare a proper defense against this new objection. Accordingly, as the appellant could not present its comments on the ground on which the decision was based, the appellant's right to be heard pursuant to Article 113(1) EPC was violated.

The refusal of the adjournment is justified in point 1.3 of the contested decision by referring to the fact that the ground of sufficiency of disclosure had been raised by the opponents already before in the written procedure. The opposition division pointed out that further data could have been filed earlier and would in any case not have been suitable for supplementing the insufficient information in the contested patent.

The board in principle agrees that further data cannot necessarily supplement the insufficient information in a patent. However, according to page 1, 4th paragraph of the minutes the appellant asked for time to provide further information, not just data, to support its arguments. Further information on the common general knowledge of the skilled person can demonstrate that information not explicitly disclosed in a patent specification nevertheless is known to the skilled person, since it belongs to the common general knowledge. Therefore the reasoning of the contested decision does not take into account the arguments presented by the appellant as indicated in the minutes.

Moreover, the appellant had no reason to expect that further information on the common general knowledge was needed at the oral proceedings, since it was not aware of the objection before the oral proceedings, in particular, since the objection raised by the opposition division is based on document D21, submitted by the appellant in preparation of the oral proceedings in a different context.

2.3 Lastly, the opposition division presented a line of argument for a lack of sufficiency of disclosure based on D16 in the decision. However, according to the minutes of the opposition division , sufficiency had not been discussed in light of D16 during the oral proceedings. Nor can the board identify in the written submissions of the then opponents the line of argument later presented in the impugned decision. This amounts to a further violation of Article 113(1) EPC.

2.4 In conclusion, the procedure leading to the contested decision contains several procedural defects, since the appellant was confronted with a new objection for the first time during the oral proceedings but did not get sufficient and adequate opportunity to prepare its defence. Furthermore, it was not made aware of the essential legal and factual reasons, that lead to the revocation of its patent, before the decision was taken. As a causal link between these procedural defects and the decision is clearly given, these defects qualify as substantial procedural violations.

2.5 Irrespective of these substantial procedural violations, constituting in the board's opinion fundamental deficiencies within the meaning of Article 11 RPBA, the appellant explicitly requested that the board, instead of remitting the case to the opposition division, should itself deal with the issue of sufficiency of disclosure. Against the background that the respondents had no objections in this regard and the issue of sufficiency of disclosure was discussed in detail in the written submissions of the appeal proceedings, the board did not remit the case pursuant to Article 11 RPBA and considered the issue of sufficiency of disclosure in accordance with Article 111(1), second sentence, EPC.

3. Article 100(b) EPC

3.1 Claim 1 is directed to a cutting tool insert comprising a cemented carbide body and a coating. The coating comprises a 1 to 20µm thick nucleated alpha-Al2O3 layer.

The alpha-Al2O3 layer is defined by its texture coefficient TC(0006), which has to have a minimum value of

TC(0006) >= 1.33 ln h + 2

where h is the thickness of the alpha-Al2O3-layer in µm and TC(0006) is defined as follows: FORMULA/TABLE/GRAPHIC

where

I(hkil) = measured intensity of the (hkil) reflection

Io(hkil) = standard intensity according to JCPDS card

no 46-1212

n = number of reflections used in the calculation

(hkil) reflections used: (1012), (1014), (1120), (0006), (1123), (1126).

3.2 The respondents argued that the skilled person is neither in the position

a) to achieve a alpha-Al2O3 layer with a strong (0001) texture as defined by the texture coefficient TC(0006) nor

b) to determine the texture coefficient TC(0006) defined in claim 1 without undue burden.

3.3 In the reasons of the impugned decision the opposition division focuses only on the ability of the skilled person to determine the texture coefficient defined in claim 1.

The board considers it more appropriate firstly to evaluate whether the skilled person is put into position to achieve a cutting tool insert comprising an alpha-Al2O3 layer with a strong (0001) texture, before going on to assess the ability to determine whether the texture coefficient as defined in claim 1 is met.

3.4 Paragraph [0002] of the contested patent refers to several documents which demonstrate that the skilled person is aware that by using CVD techniques alpha-Al2O3 layers with various textures can be obtained.

The contested patent starts from this knowledge of the skilled person and proposes a cutting tool comprising an alpha-Al2O3 coating having a strong (0001) texture as defined by the TC(0006) in claim 1. According to the last two sentences of paragraph [0026] of the contested patent, a strong texture in (0001) orientation was unknown at the priority date of the contested patent and can only be achieved when both, nucleation and growth are controlled correctly.

Therefore according to the contested patent the skilled person was aware that different grain orientations could be obtained when depositing an alpha-Al2O3 layer, but was not aware of a method of manufacturing an alpha-Al2O3 layer having a sufficient high amount of the required (0001) texture as expressed by the TC(0006) value defined in claim 1.

3.5 Therefore the question arises whether the contested patent provides the necessary information to the skilled person for obtaining the required stronger (0001) texture.

The board observes in this context that the contested patent does not provide any detailed teaching concerning the apparatus and the specific conditions of the various coating steps, such as the composition of the gas mixture, gas flow, duration and pressure, which can be used to manufacture the cutting tool insert defined in claim 1. In particular, no detailed example is presented which guides the skilled person to achieve the required texture of the alpha-Al2O3 layer.

The appellant confirmed during the oral proceedings before the board, that the orientation of the deposited alpha-Al2O3 differs from apparatus to apparatus. Even on an identical apparatus the same orientation cannot be obtained consistently without further modification of the process steps.

Therefore it can be concluded that the orientation obtained by depositing alpha-Al2O3 is highly sensitive to the process conditions and apparatus used.

If a manufacturing method is extremely sensitive to the experimental setup, the board considers it to be particularly important that the skilled person is informed at least on the critical parameters and their influence on the intended outcome of the manufacturing process, since he cannot rely on a best practice known from the common general knowledge.

Should the skilled person have to rely on a mere chance, as to whether or not he obtains the desired product, the invention cannot be regarded as being described sufficiently.

3.6 The sole information concerning the manufacturing process for achieving the alpha-Al2O3 layer with a strong (0001) texture can be found in paragraph [0026] on page 5 of the contested patent.

3.6.1 On page 5, lines 23 to 26 it is disclosed that

"The alpha-Al2O3 layer is deposited on a bonding layer of (Ti,Al)(C,O,N) preferably with increasing aluminium content towards the outer surface. Onto this layer a Ti(C,O) layer is deposited with controlled O-content.

A nucleation layer is obtained in the similar way as used in ALD (Atomic Layer Deposition)."

The appellant confirmed during the oral proceedings that the alpha-Al2O3 layer should be deposited on the Ti(C,O) layer and that the Ti(C,O) layer is deposited on a bonding layer of (Ti,Al)(C,O,N) which has an increasing aluminium content towards the outer surface.

The board accepts that the skilled person would interpret the first lines of paragraph [0026] in the same manner as the appellant.

However, it is observed by the board that the contested patent does not disclose any process details for depositing the Ti(C,O) layer and the (Ti,Al)(C,O,N) layer, despite the fact that these layers have an influence on the formation of the nucleation layer and consequently on the formation of the texture.

3.6.2 On page 5, lines 26 to 34 the procedure for forming the nucleation layer is presented:

"(i) exposure of a first precursor TiCl4, preferably together with AlCl3,

(ii) purge (N2),

(iii) exposure of the second precursor (H2O) and

(iv) purge (N2).

The duration of the steps (i) and (iii) is 1-5 min, preferably 2 min each and the steps (ii) and (iv)

2-10 min, preferably 5 min each."

The formation of the nucleation layer is an important process step when aiming at a specific orientation, since the final orientation is mainly influenced by the nucleation layer, as was confirmed by the appellant during the oral proceedings.

However, paragraph [0026] only describes in general terms the reactants and a commonly used sequence of steps. These reactants and general process steps can equally be used to obtain alpha-Al2O3 layers with different orientations, as is described in D10 (examples) and D16 (table 2). A specific teaching of the process parameter(s) that should be given particularly attention, in order to promote a strong (0001) texture is not disclosed in paragraph [0026], despite the fact that it is repeatedly stated that the nucleation step has to be performed "correctly", see page 5, lines 37 to 38 and 44 and 45.

In the absence of any indication what the correct nucleation conditions are, the skilled person has to guess what is meant by the term "correctly".

The contested patent therefore does not provide sufficient teaching for creating a nucleation layer that would lead to a strong (0001) orientation.

3.6.3 The appellant argues that the skilled person is taught by the patent that the stronger (0001) texture can be obtained by a deposition process using a CO+CO2 gas mixture, where CO = 2.5-5.5 x CO2 (page 5, lines 41 to 42).

During the oral proceedings the appellant explained that the CO/CO2 ratio is important for improving the kinetics of the alpha-Al2O3 layer formation, i.e. it is important to achieve fast layer growth.

However, setting a parameter for obtaining fast growth of the alpha-Al2O3 layer does not alone necessarily lead to the formation of a specific dominant orientation. Thus, it is not credible that the skilled person can achieve a strong (0001) texture simply by adapting the CO/CO2 ratio.

This is confirmed by document D2, which is referred to in example 3 of the contested patent although it has been published after the priority date of the contested patent. D2 discloses a manufacturing process for achieving a strong (0001) texture (see table 1 of D2), which is achieved by a CO/CO2 ratio of 2 (see paragraph [0044] of D2), which is lower than the ratio indicated in paragraph [0026] of the contested patent. Hence the required texture cannot result merely from the CO/CO2 ratio.

3.7 In summary, the contested patent teaches that careful control of both the nucleation and growth steps is required, but does not teach the required technical details to perform the manufacturing process "correctly".

Furthermore should the skilled person have an initial idea of how to start the nucleation step and how generally to perform the growth step on a given apparatus, there is no guidance in the contested patent and in particular paragraph [0026] of how to modify the parameters governing nucleation and growth when the desired texture is not immediately obtained.

The skilled person has therefore to rely on mere chance or pure speculation and guess work to modify a given process in case of failure to obtain the desired texture.

3.8 The appellant argues that the lack of explicit technical teaching in the contested patent is filled by the common general knowledge of the skilled person, as confirmed by decision T 2372/10. This decision concerned a patent application of the appellant, different from one on which the patent in suit is based, but in the same technical field. Under point 3.3 of the reasons textured alpha-Al2O3 is discussed and the question of sufficiency with regard to the disclosure of the CVD method of obtaining different texture coefficients is answered in the affirmative.

The present board agrees with the reasoning in point 3.3 of decision T 2372/10 that a skilled person with a high level of operating experience and expert knowledge is required to achieve a textured alpha-Al2O3 layer, in particular since different reactors necessitate type-specific conditions.

This is also confirmed by the various prior art documents cited in paragraph [0002] of the contested patent, which propose methods for achieving textured alpha-Al2O3 layers.

However, in the present case the invention underlying the contested patent goes beyond merely obtaining a alpha-Al2O3 layer with a (0001) texture, in that it aims to have a particularly strong (0001) orientation, which has been unknown so far (see last sentence of paragraph [0026] of the contested patent).

Therefore the contested patent itself indicates that the common general knowledge forming the basis of the reasoning in decision T 2372/10 is not sufficient for obtaining a textured alpha-Al2O3 as claimed, since this was achieved for the first time by the inventor of the contested patent.

Hence, the reasoning in decision T 2372/10 is not contested by the present board but does not apply to the present case.

3.9 The appellant further argues that scientific articles such as D22, which was written by Mr. Ruppi, the inventor of the contested patent, demonstrate that the skilled person at the priority date of the contested patent was aware of the factors which influence the orientation of crystal growth. According to the appellant, D22 confirms that the skilled person is aware that very small adjustments of the experimental data are sufficient to modify the coating texture. Performing minor adjustments does not require an undue amount of experimentation.

The board is not persuaded by this argument. D22 is neither a general textbook reflecting the common general knowledge nor was it publicly available at the priority date of the contested patent.

Therefore D22 does not demonstrate that a standard method for obtaining the strong (0001) texture required by claim 1 was known to the skilled person at the priority date of the contested patent.

Furthermore, the board accepts that D22 discloses in section 2.1. that only very small adjustments of the experimental data are needed to modify the coating texture. However, it does not disclose how these adjustments have to be made and which experimental setup was used for performing the experiments. Moreover, the statement that minor adjustments are already enough to change the coating confirms that the process described in D22 is highly sensitive. Thus, it is the more important that the skilled person gets sufficiently detailed information on how to obtain the desired texture with a reasonably high expectation of success. However, this information is missing from D22 as is for the contested patent.

3.10 The appellant further argues that the contested patent relates to a specific field of research which is pursued only by a very limited number of experts worldwide, each expert working on a different apparatus. Therefore a meaningful, general guidance cannot be given, since specific process parameters are only meaningful for a specific experimental setup and vary from apparatus to apparatus. Nevertheless, the skilled practitioner working for years in this field has no problem in obtaining a textured alpha-Al2O3 layer and is well aware of the possible options to influence the texture.

The board accepts that the contested patent relates to a technical field in which only a limited number of experts are working and that the process conditions highly depend on the apparatus and the skilled person.

Thereby it can even be expected that an expert has a certain experience to adapt a known specific process running on one apparatus to the particularities of his experimental setup by using his experimental experience.

However, in the absence of any indication which equipment and which process has been used in detail in the experiments reported in the contested patent, the skilled person has to start his own research program to find the appropriate conditions. This clearly constitutes an undue burden.

3.11 In summary the board comes to the conclusion that the contested patent does not contain sufficient information to obtain without undue burden a cutting tool insert comprising a textured alpha-Al2O3 layer which is orientated in the (0001) direction to an extent as required by claim 1. Therefore it is decided that Article 100(b) EPC prejudices the maintenance of the patent as granted.

4. Reimbursement of the appeal fee

According to Rule 103(1)(a) EPC, the appeal fee shall be reimbursed in full in the event of interlocutory revision or where the board deems an appeal to be allowable, if such reimbursement is equitable by reason of a substantial procedural violation.

A number of substantial procedural violations had occurred in the present case and a causal link between them and the filing of the appeal cannot be denied. However, as the case was not directly remitted, the reimbursement of the appeal fee further depends on the final outcome of the appeal. As the board, in its assessment of the issue of sufficiency of disclosure under Article 100(b) EPC, comes to the conclusion that the patent as granted cannot be upheld, the appeal cannot be allowed. Accordingly, the appeal fee is not reimbursed pursuant to Rule 103(1)(a) EPC.