T 0516/22 13-12-2024

1. Decision in written procedure

Pursuant to Article 15(3) RPBA, the board is not obliged to delay any step in the proceedings, including its decision, by reason only of the absence at the oral proceedings of a duly summoned party, which may then be treated as relying only on its written case.

In the current case, both parties had requested oral proceedings as an auxiliary measure. In response to a communication under Article 15(1) RPBA, in which the board provided its preliminary opinion that the appeal was likely to be dismissed, the appellant filed further submissions and announced that it would not attend the oral proceedings before the board. The oral proceedings were subsequently cancelled.

In the communication under Article 15(1) RPBA, the parties had been made aware of the board's intention to dismiss the appeal and the reasons for this. By deciding not to attend the oral proceedings, the appellant effectively chose not to avail itself of the opportunity to present its observations and counter-arguments orally but instead to rely on its written submissions.

2. Patent as granted - Ground for opposition under Article 100(a) in conjunction with Article 54 EPC

2.1 Novelty in view of document D1

The appellant submits that feature 1.8' was disclosed by Example 1 shown in Figure 1 of document D1, specifically referring to UCAR**(TM) VMCH (mentioned in paragraph [0059] of document D1) and documents D15 and D15A. The respondent takes the view that no objection of lack of novelty had been raised in the opposition proceedings in view of Example 1 of document D1. The appellant submits that various passages of document D1 had been cited in the notice of opposition and the appellant's letter dated 17 September 2021 and that also two-layer systems had been addressed. In the appellant's view, its appeal case had not been amended.

In accordance with Article 12(6), second sentence, RPBA, the board does not admit requests, facts, objections or evidence which should have been submitted, or which were no longer maintained, in the proceedings leading to the decision under appeal, unless the circumstances of the appeal case justify their admittance.

No objection of lack of novelty had been raised in the opposition proceedings against the first alternative of claims 1 and 8 as granted in view of Example 1 of document D1. Moreover, factual allegations concerning UCAR**(TM) VMCH and its material properties had not been discussed in the opposition proceedings. The above objection has instead been raised for the first time in the appellant's statement of grounds of appeal. Since this objection is directed against granted claims, it could and should have been raised in the opposition proceedings. Circumstances of the appeal case that would justify the admittance of this objection have not been set out by the appellant, nor are such circumstances apparent. The board therefore exercised its discretion under Article 12(6) RPBA and decided not to admit the novelty objection against the first alternative of claims 1 and 8 in view of Example 1 of document D1 into the appeal proceedings.

2.2 Novelty in view of document D2

The appellant submits that the subject-matter of the first alternative of claims 1 and 8 as granted was not new in view of Example 1 of document D2.

It is common ground between the parties that document D2 belongs to the prior art for these claim alternatives. The board shares this view. The parties are, however, at odds over whether the priority right for these claim alternatives is validly claimed and whether, accordingly, document D2 belongs to the state of the art under Article 54(2) or (3) EPC. However, in either case, document D2 would have to be considered state of the art for novelty. The validity of the priority claim therefore does not have a bearing on the discussion of novelty (for the assessment of inventive step, see points 3.2 and 3.3 below).

Regarding feature 1.8', the appellant submits that the term "flexible" had no limiting effect and, since this was an unusual parameter, the burden of proof for the disclosure of this feature in the prior art had shifted to the respondent.

However, the appellant has not convincingly demonstrated that the flexibility of a material was an unusual parameter in the relevant technical field. Even assuming that the skilled person understood the term "flexible" as referring, for example, to the modulus of elasticity or flexural strength (as suggested by the appellant), this merely implies that there are different ways in which it can be assessed whether one material is more flexible than the other. It is undisputed that methods for measuring the modulus of elasticity or flexural strength are commonly known. The skilled person does thus not depend on the patent for such measuring methods. The fact that no such methods are specifically disclosed in the patent is therefore not pertinent to the question in hand.

Moreover, feature 1.8' does not require specific absolute parameter values for the flexibility of the materials. It specifies a relative difference in flexibility between two materials. To assess whether feature 1.8' is met, it is thus not even necessary to measure the flexibility of the materials in absolute terms. It would be sufficient to test a sample of each material using the same test in each case to determine their relative flexibilities, as suggested by the respondent. Since only a relative difference in flexibility between two materials is specified, the fact that no specific absolute values for the flexibility of the materials are stated in the patent is not relevant.

The appellant refers to Case Law, I.C.5.2.3. In decision T 1764/06 (cited in that section of Case Law), the board took the following view:

"In a situation where the applicants have used an unusual parameter feature to define their product, which unusual parameter feature represents the only distinction over otherwise identical known products, and the applicants have decided not to provide evidence that the parameter feature as such represents a difference of the claimed products from the known products, no benefit of doubt can be accorded"

In decision T 131/03 (also cited in Case Law, I.C.5.2.3 and III.G.5.2.2.d)), the board set out the following:

"In inter-partes proceedings the burden of proof rests primarily upon the opponent. However, when the latter has established a strong presumption that unusual parameters as used to define the claimed subject-matter are inherently disclosed in the prior art, the patent proprietor cannot merely claim the benefit of the doubt. It is incumbent upon him to contribute in establishing to which extent such parameters, which he freely chose to use in the definition of his invention, actually distinguish the claimed subject-matter from the prior art."

However, in the case at hand, the appellant has not convincingly shown or established a strong presumption that the expression "more flexible" refers to a parameter that is unusual in the relevant technical field. Nor is this apparent from the cited case law. Decisions T 131/03 and T 740/01 do not address whether the definition that one material was more flexible than another material refers to an unusual parameter in the technical field of security devices.

Following the appellant's line of argument, there are different ways in which it can be assessed whether the specification in feature 1.8' is met. The burden remains on the appellant to convincingly demonstrate that the skilled person (for example, applying one such commonly known method) considers the materials used in the security devices of the prior art to meet this specification. There is no reason why feature 1.8' should be disregarded for the assessment of novelty or inventive step.

The appellant submits that the different proportions of TPGDA in the layers 1 and 2 of Example 1 of document D2 as well as the presence of multifunctional urethane acrylate in layer 2 lead to different extents of cross-linking of the materials of these layers.

However, even if the cross-linking influences the flexibility of the material, it cannot be unambiguously derived from the disclosure of Example 1 of document D2 that the material of layer 1 is necessarily more flexible than the material of layer 2 once fully cured.

The appellant submits that document D2 disclosed that the layers 1 and 2 could be made of the same material and that the layer 1 was applied with a lower coating weight or in a thinner layer thickness than the layer 2. As a result, the thinner layer 1 exhibited greater flexibility than the layer 2.

However, feature 1.8' defines that:

"the at least one transparent material (207) forming the pedestal layer (249) is more flexible than the at least one transparent curable material (205) applied in step (a)(i) once fully cured" (Underlining added by the board.)

Feature 1.8' thus explicitly refers to the material forming the pedestal layer rather than to the pedestal layer itself and compares the flexibility of this material with that of the curable material 205. If, however, in an embodiment of Example 1 of document D2, the materials of the layers 1 and 2 are identical, the flexibility of these materials cannot be different. The appellant has not convincingly demonstrated that the thickness of a layer has any influence on the flexibility of the material used to form that layer.

The above claim interpretation is not contradicted by paragraph [0023], [0090], [0111] or [0113] of the patent, cited by the appellant. These paragraphs do not relate to feature 1.8'. For example, according to paragraph [0113] of the patent, the focusing elements may be formed from a flexible material too. However, it is not disclosed that the pedestal layer and the focusing elements in the same device are formed from the same flexible material.

The appellant submits that it was possible to imagine situations in which certain materials achieved the same value in one of the measurable parameters relating to the flexibility of the material but not in the other. However, the appellant has not convincingly shown that the materials disclosed in the context of Example 1 of document D2 meet the specification of feature 1.8' in view of a measurable parameter relating to the flexibility of the materials that the skilled person would consider. The hypothetical question of whether feature 1.8' was not met in view of a further measurable parameter relating to the flexibility of the materials is therefore irrelevant.

At least features 1.8' and 8.5' are not disclosed by Example 1 of document D2, such that the subject-matter of claims 1 and 8 as granted is new over document D2.

2.3 Novelty in view of document D3

The appellant submits that the first alternative of claim 8 was not new in view of the embodiment shown in Figure 10a of document D3. The respondent is of the opinion that document D3 did not disclose, inter alia, feature 8.5'. Regarding this feature, the appellant argues that document D3 explicitly disclosed that only the layer 21 (see Figure 10a) was compressed or deformed under mechanical pressure but not the microlenses 19a.

Figure 10b of document D3 shows a deformed, compressed state of the elastically deformable intermediate layer 21. However, from this illustration, it cannot be unambiguously and directly derived that other components of the device shown in that figure, such as the microlenses 19a, are not elastically deformable. Nor can this be inferred from the use of the reference numerals 4, 4d and 4e in the embodiment of Figures 16a and 16b of document D3. Even if it is not specifically stated in document D3 that the microlenses 19a in Figures 10a and 10b are flexible, this does not mean that the opposite is disclosed. Nor does the fact that the microlenses 19a retain the ability to focus light furthermore imply that they are not deformed under the mechanical pressure. It is technically possible that also a (slightly) deformed lens retains the ability to focus light. More importantly, it cannot be unambiguously and directly derived from document D3 that the material of the layer 21 is more flexible than the material of the microlenses 19a.

At least feature 8.5 is thus not disclosed in document D3, such that the subject-matter of claim 8 is new over that document.

2.4 Novelty in view of document D4

The appellant submits that document D4 disclosed the first alternative of claims 1, 8 and 15 as granted. Feature 1.8' was implicitly disclosed in document D4. That document disclosed that the transparent ink (used to create the lenses) comprised a UV-curable embossable lacquer or an acrylic-based coating or a coating based on other components such as nitrocellulose. These were not elastomeric. Document D4 furthermore disclosed that the primer layer was formed of a polyurethane which was elastomeric (as disclosed on pages 137, 138 of document D13).

The appellant has not submitted any evidence for its allegation that the acrylic-based or nitrocellulose-based coating disclosed in document D4 was necessarily less flexible than the polyurethane used in the primer disclosed in document D4. The appellant submits that paragraphs [0111] to [0113] of the patent disclosed that acrylic-based or nitrocellulose-based coating could be used for the curable material 205. This, however, does not imply that the polyurethane used for the primer in document D4 was necessarily more flexible than the acrylic-based or nitrocellulose-based coating disclosed in document D4. Polyurethane as well as acrylic-based and nitrocellulose-based coatings form classes of compounds in which each compound may have different properties. Even assuming that a specific polyurethane material is known that is more flexible than a specific acrylic-based coating, this would not imply that feature 1.8' is disclosed in document D4. This view is not altered by the appellant's reference to document D13, which discloses that there are polyurethane compounds that are elastic without, however, indicating that each and every polyurethane compound was more flexible than all acrylic-based or nitrocellulose-based coatings.

Nor is this view affected by the appellant's allegation that, in document D4, the primer layer was thinner than the transparent ink. Even if this was true, it could not be unambiguously derived that the material of the primer layer must be more flexible than the material of the transparent ink.

Feature 1.8' (and, for the same reasons, features 8.5' and 15.9') are not disclosed in document D4. Consequently, the subject-matter of claims 1, 8 and 15 as granted is new in view of that document.

2.5 Novelty in view of document D5

The appellant submits that the first alternative of claims 1 and 8 (including features 1.8' and 8.5', respectively) was not new in view of document D5.

Regarding feature 1.8', the appellant submits that the polymer resin 20 used to form the lenses in document D5 could be an acrylic-based resin such as an acrylated urethane polyester oligomer which, according to the appellant, formed a hard, brittle material. The binder coating 13 was disclosed in document D5 as being a polymethyl acrylic. The appellant concludes that it must thus implicitly be flexible.

An alleged disclosure can only be considered "implicit" if it is immediately apparent to the skilled person that nothing other than the alleged implicit feature forms part of the subject-matter disclosed (see Case Law, I.C.4.3).

There is no reason to assume that the polymethyl acrylic binder coating 13 disclosed in document D5 must necessarily be more flexible than the resin 20 used to form the lenses and that, thus, nothing other than this forms the subject-matter disclosed in document D5. Even assuming that document D5 discloses that the polymethyl acrylic forming the binder coating 13 had some degree of flexibility, this would not imply that it is necessarily more flexible than the material forming the polymer resin 20, irrespective of the compound used for the polymethyl acrylic or the polymer resin 20. Nor can this unambiguously and directly be derived from paragraph [0091] of the patent.

At least features 1.8' and 8.5' are not disclosed in document D5 such that the subject-matter of claims 1 and 8 as granted is new in view of document D5.

2.6 Novelty in view of document D10

The appellant submits that the embodiment shown in Figure 9 of document D10 disclosed all features of the second alternative of claim 8 as granted.

Regarding features 8.2 and 8.5'', the appellant refers to page 27, lines 15 to 26 of document D10, which is part of the description of the embodiment shown in Figure 8.

In the Reasons for the decision under appeal, the opposition division set out that the appellant had combined features of different embodiments (i.e. the embodiments shown in Figures 8 and 9 of document D10). It was, however, not permissible, for assessing novelty, to combine separate items belonging to different embodiments described in the same document, unless such a combination had specifically been suggested, which was not the case here. In any case, no explicit disclosure could be found in document D10 that the layer 102 might be transparent.

The appellant submits that a combination of features relating to the layer 102 disclosed in the context of the embodiments of Figures 8 and 9 was suggested by page 28, lines 1, 2 and 17 to 19 of document D10.

The cited passages refer to the embodiment shown in Figure 9 whose description starts on page 27, line 28 of document D10. Page 28, lines 1 and 2 of document D10 discloses that the mask layer 102 (see Figure 9) is formed by a laser-absorbing or laser-reflecting printed layer. Page 28, lines 17 to 19 of document D10 discloses that, outside of the gap region 34, in contrast, the incident laser radiation is absorbed or reflected, such that no microholes are produced in the recording layer 40 there. Neither of these passages refers to the embodiment shown in Figure 8 of document D10 or, more specifically, to details of the laser-absorption layer 92 disclosed for the embodiment of Figure 8 on page 27, lines 15 to 26 of document D10. For assessing novelty, it is therefore not permissible to combine such details disclosed in the context of the embodiment shown in Figure 8 of document D10 with other features disclosed in the context of Figure 9 of document D10. The skilled person cannot unambiguously and directly derive that the mask layer 102 is transparent. This view is unaffected by the appellant's submission that the patent discloses that transparent materials may be optically detectable. This disclosure does not support the conclusion that all optically detectable materials are transparent.

The appellant submits that the combination of the mask layer 102 and the material filling the gap region 34 in Figure 9 of document D10 constituted a pedestal layer.

Even assuming that the skilled person considered the combination of the mask layer 102 and the material filling the gap region 34 in Figure 9 of document D10 to be a pedestal layer, the only transparent material of that "pedestal layer" would be the material filling the gap region 34. However, it is not unambiguously and directly derivable from document D10 that the material filling the gap region 34 comprises at least two transparent materials having different optical detection characteristics, as defined in feature 8.5''.

Consequently, at least feature 8.5'' is not disclosed by the embodiment shown in Figure 9 of document D10, such that the subject-matter of claim 8 is new over that document.

2.7 Novelty in view of document D11

The appellant sets out that the subject-matter of the first alternative of claim 8 (including feature 8.5') was disclosed in document D11. It refers to paragraphs [0072] and [0073] of document D11 and infers from these passages that the material of the optical spacer 18 was more flexible than the material of the focusing element layer 14.

Paragraph [0072] of document D11 discloses that the focusing element and icon layers 14, 16 are usually cross-linkable thermoset layers and that increased radiation exposure times do not serve to alter the stiffness of the optical spacer, so it retains flexibility relative to the icon layer. This, however, does not imply that the material of the optical spacer 18 must necessarily be more flexible than the material of the focusing element layer 14. Moreover, the fact that paragraph [0073] of document D11 discloses that the focusing element layer 14 retains its good wear and abrasion resistance does not have any bearing on whether its material is less flexible than the material of the optical spacer 18.

Feature 8.5' is thus not disclosed in document D11, such that the subject-matter of claim 8 is new over that document.

2.8 Novelty in view of document D12

The appellant is of the opinion that the subject-matter of the third alternative of claim 8 (including feature 8.5''') was disclosed by the embodiment of Figure 10 of document D12.

In a first line of argument, the appellant submits that the lens support mesa 144 shown in Figure 10 of document D12 was a pedestal layer within the meaning of claim 8 as granted.

FORMULA/TABLE/GRAPHIC

The respondent contests this view and submits that the lens support mesa 144 was not a separate layer from the lens 140 formed on its top. In its view, claim 8 as granted required the provision of the focusing element array and the pedestal layer as distinct components.

This issue can be left open since, even if the lens support mesa 144 was considered a pedestal layer, it does not have a first height in a first sub-region and a second different height in a second sub-region, as defined in feature 8.5'''. The appellant has not convincingly shown that the skilled person would consider the absence of the lens support mesa in a sub-region to be the same as the presence of a lens support mesa having a height of zero. Nor is such an interpretation supported by paragraphs [0018] and [0019] of the patent.

In a second line of argument, the appellant considers the combination of the lens support mesa 144 and the optical separation 150 to be a pedestal layer and the icon separator 154 to be a focusing element support layer as defined in claim 8 as granted. Referring to paragraph [0038] of the patent, the appellant submits that the patent did not define the focusing element support layer as a support layer.

The appellant has not convincingly demonstrated that the skilled person would have considered the icon separator 154 to be a focusing element support layer as defined in claim 8 as granted. Based on their common general knowledge, the skilled person would have understood the term "focussing element support layer" to be a layer that supports the focusing elements.

This view is not in contradiction with paragraph [0038] of the patent. It is not derivable from this paragraph that the focusing element support layer would not have the function of supporting the focusing elements. This paragraph discloses that the focusing element support layer is a layer on the surface from which the focusing elements are formed, which is implied by feature 8.2. Examples are then given in which the focusing element support layer is a polymer substrate or another layer which is applied to a document substrate or used as a carrier from which the focusing elements are later transferred to a document substrate. These are examples in which the focusing element support layer typically acts as a support for the focusing elements.

Paragraph [0038] of the patent therefore does not indicate that the above common understanding of the skilled person would be wrong. It is not derivable from this paragraph that the expression "focussing element support" in "focussing element support layer" must be ignored or that it does not imply any technical features. Nor are the arrangements shown in Figures 12(a), (b) and (c) of the patent in contradiction with this claim interpretation.

The appellant has not convincingly shown that the icon separator 154 shown in Figure 10 of document D12 is a layer that supports the focusing elements. The skilled person would not have considered the icon layer spacer 154 to be a focusing element support layer. If the appellant's second line of argument was accepted, features 8.2, 8.3., 8.4 and 8.5''' would therefore not be disclosed in document D12.

The subject-matter of claim 8 as granted is thus new over document D12.

2.9 Dependent claims as granted

The subject-matter of the dependent claims as granted is new at least for the same reasons set out above for the independent claims.

2.10 Summary on the ground for opposition under Article 100(a) in conjunction with Article 54 EPC

The ground for opposition under Article 100(a) in conjunction with Article 54 EPC does not prejudice the maintenance of the patent as granted.

3. Patent as granted - Ground for opposition under Article 100(a) in conjunction with Article 56 EPC

3.1 Example 2 of document D1 as the closest prior art

The appellant submits that the subject-matter of the first alternative of claims 1 and 8 as granted (including features 1.8' and 8.5', respectively) did not involve an inventive step in view of Example 2 (i.e. the embodiment shown in Figure 2) of document D1. The appellant is of the opinion that the substrate 10 in Figure 2 of document D1 is a focusing element support layer as defined in the claims and that document D1 discloses that the layer 3 shown in Figure 2 is provided with microlenses.

It is common ground between the parties that feature 1.7 is not disclosed by Example 2 of document D1. The appellant considers that the objective technical problem is to suggest an alternative method of making a security device with a focusing element array cooperating with an image element array. The respondent contests this view.

Example 2 of document D1 does not involve cooperation between a focusing element array and an image element array. The claimed solution therefore cannot be seen as suggesting an alternative solution in this regard.

The appellant's line of argument is also not convincing for the following reasons.

Paragraph [0067] of document D1 mentions an embossing of layer 3 but does not disclose that the layer 3 is provided with microlenses or, for that matter, that the security element shown in Figure 2 includes an image element array. Nor can this be derived from paragraph [0006] or [0035] or claim 1 or 10 of document D1.

Even assuming that the skilled person was prompted to emboss layer 3 shown in Figure 2 of document D1 to provide it with an array of microlenses, it is not apparent why the focal plane of the microlenses provided in layer 3 must be located on the first surface of the substrate 10 or at any point beyond that first surface.

The appellant refers to paragraphs [0004] and [0006] of the patent and derives from these passages that the focal plane of typical security elements was substantially on the surface of a support (adjacent to the spacer) or on or outside the second surface of the spacer layer serving as a support. According to the appellant, this was also the case for the security elements discussed in document D1.

Paragraphs [0004] and [0006] of the patent do not belong to the prior art. Moreover, paragraph [0004] of the patent discloses that "[s]ecurity devices comprising focussing elements typically require [...]" (underlining added by the board). It is not apparent, let alone unambiguously and directly derivable from document D1, that Example 2 of document D1 concerns such a "typical" security device discussed in the cited passages of the patent.

The appellant also submits that to provide the desired microlens effect (see paragraph [0006] of document D1), the focal plane of the microlenses of such a security element must be located on the first surface of the substrate (which the appellant identifies as the focusing element support layer) or at any point beyond the first surface of the substrate.

However, the security element according to Example 2 of document D2 does not include an image element array. Moreover, the substrate 10 shown in Figure 2 of document D1 is not the substrate of the final security element since the layers 1, 2 and 3 are transferred to a security document (see, for example, paragraph [0061] of document D1).

The appellant submits that the skilled person would have considered using the layer 3 provided with a microlens structure as the surface of a security element not to be applied but provided, for example, in the form of a security strip embedded in a security paper (see document D1, paragraph [0044] and claim 12).

However, the appellant has not set out any reasons why the skilled person would be prompted to do so. Although paragraph [0044] and claim 12 of document D1 mention strip-based security elements, there is no suggestion to use the arrangement of Figure 2 including substrate 10 as a strip-based security device, i.e. without a transfer process.

Since, according to the disclosure of document D1, the substrate 10 shown in Figure 2 is not present in the final security element after transfer, it was not obvious to arrange the focal plane of microlenses provided in layer 3 with particular reference to that substrate 10, i.e. on a surface of that substrate or beyond that surface. This holds true, in particular, when layer 1 is the outer layer of the transferred security element and the viewer looks at the document through layers 1, 2 and 3.

The subject-matter of claim 1 and, for, mutatis mutandis, the same reasons, claim 8 involves an inventive step in view of Example 2 of document D1 as the closest prior art.

3.2 Document D6 in combination with the common general knowledge or document D1 or D2

The appellant submits that the subject-matter of the first alternative of claims 1 and 8 (including features 1.8' and 8.5') as granted did not involve an inventive step in view of a combination of document D6 and the common general knowledge or document D1 or D2.

It is common ground between the parties that document D6 does not disclose feature 1.8'. The respondent submits that document D6 also failed to disclose feature 1.1 and that it was furthermore not an appropriate starting point for the examination of inventive step.

However, even if starting from document D6 as the closest prior art and assuming that feature 1.8' was the only differentiating feature of the first alternative of claim 1, the subject-matter of claim 1 would not have been obvious in view of that document for the following reasons.

The respondent suggests that the objective technical problem solved was how to reduce damage to the focusing elements during handling.

The appellant contests this view. It submits that claim 1 as granted did not exclude the possibility that the material of the pedestal layer was hard, rigid and brittle. The number of materials and material thicknesses covered by the claim was such that it was inherently unlikely that all the claimed materials (or at least substantially all of them) would have a buffering/attenuation function.

However, even assuming that there is only a small difference in the flexibility of these materials, this would still achieve a reduction in damage caused to the lenses during handling since the pedestal layer would still deflect and/or absorb deflections to some degree. This technical effect is achieved in view of feature 1.8' across the whole ambit of the claim. This view is unaffected by the consideration that the degree to which the pedestal layer deflects and/or absorbs deflections may vary depending on the degree of flexibility of the material used and that further features (that are not included in claim 1) may be present which also influence the robustness of the security element.

The objective technical problem is therefore how to reduce damage to the focusing elements during handling.

Documents D1 and D2 do not address the objective technical problem. The skilled person would not have been prompted to consult either of these documents when trying to solve it. Even if they did, the skilled person would not have found any solution to the objective technical problem, let alone the solution defined in claim 1 as granted. Nor has the appellant convincingly demonstrated that the claimed solution to the objective technical problem was commonly known.

The subject-matter of the first alternative of claim 1 (and, for the same reasons, claim 8) as granted was not obvious in view of a combination of document D6 and the common general knowledge or one of documents D1 and D2.

In this situation, it can be left open whether document D2 belongs to the state of the art under Article 54(2) or (3) EPC.

3.3 Further objections of lack of inventive step

In point 6.1 of the statement of grounds of appeal, the appellant submits that the subject-matter of claims 1, 8 and 15 as granted did not involve an inventive step in view of any of documents D1, D2, D4, D5, D10, D11 and D12. It explains that a detailed discussion of inventive-step activity could not be presented with the statement of grounds of appeal since this would require that there was at least one distinguishing feature between the claimed subject-matter and the content of document D1. The appellant refers to Case Law 2019, IV.C.3.4.2, second paragraph.

The cited passage of Case Law 2019 is taken from section IV.C.3.4, "Fresh grounds for opposition". It addresses a situation in which a patent has been opposed on the grounds of lack of novelty and lack of inventive step, and only the ground of novelty has been substantiated. The passage sets out circumstances under which the objection of lack of inventive step is considered not to constitute a fresh ground for opposition although the ground of lack of inventive step has not been specifically substantiated.

In the case in hand, it is undisputed that the ground for opposition under Article 100(a) in conjunction with Article 56 EPC was raised in the notice of opposition and that it does not constitute a fresh ground for opposition.

The question whether the ground for opposition of lack of inventive step is a fresh ground for opposition is different from whether an objection of lack of inventive step raised in the statement of grounds of appeal meets the requirements of Article 12(3) RPBA. In accordance with this provision, the statement of grounds of appeal and the reply must contain a party's complete appeal case. Accordingly, they must set out clearly and concisely the reasons why it is requested that the decision under appeal be reversed, amended or upheld, and should expressly specify all the requests, facts, objections, arguments and evidence relied on. In accordance with Article 12(5) RPBA, the board has discretion not to admit any part of a submission by a party which does not meet the requirements in Article 12(3) RPBA.

In the case at hand, the requirements set out in Article 12(3) RPBA are only met for the objections of lack of inventive step addressed in points 3.1 and 3.2 above. The mere reference to documents D2, D4, D5, D10, D11 and D12 as the closest prior art in the statement of grounds of appeal does not render it self-explanatory that the subject-matter of claim 1, 8 or 15 as granted does not involve an inventive step in view of any of these documents. The board, exercising its discretion under Article 12(5) RPBA, does not admit any of these objections into the appeal proceedings.

3.4 Dependent claims as granted

The subject-matter of the dependent claims as granted involves an inventive step at least for the same reasons set out above for the independent claims.

3.5 Summary on the ground for opposition under Article 100(a) in conjunction with Article 56 EPC

The ground for opposition under Article 100(a) in conjunction with Article 56 EPC does not prejudice the maintenance of the patent as granted.

4. Conclusions

Since none of the grounds for opposition raised by the appellant prejudices the maintenance of the patent as granted, the appeal has to be dismissed.