T 0798/23 24-01-2025

I. Both the opponent and the patent proprietor filed an appeal against the interlocutory decision of the opposition division finding that European patent No. 2 949 452 as amended according to the second auxiliary request met the requirements of the European Patent Convention.

II. The opposition was filed against the patent as a whole on the basis of the grounds for opposition under Article 100(a) together with Article 54(1) EPC (lack of novelty) and Article 56 EPC (lack of inventive step), under Article 100(b) EPC and under Article 100(c) EPC.

III. In the decision under appeal, the opposition division came, inter alia, to the conclusion that the ground for opposition under Article 100(a) EPC together with Article 54(1) EPC prejudiced the maintenance of the patent as granted, and that the requirements of Article 123(2) EPC were not met in respect of claim 1 of the first auxiliary request. The opposition division in particular considered document EP 2 923 820 A1 (D2).

IV. With its statement of grounds of appeal the patent proprietor (appellant I) filed five sets of claims according to the main request and auxiliary requests 1 to 4.

V. The parties were summoned to oral proceedings, as requested. In a communication pursuant to Article 15(1) RPBA issued on 8 October 2024, the parties were informed of the board's provisional opinion on the issues of the case.

VI. By letter dated 23 January 2025 appellant I informed the board that it would not attend the oral proceedings and changed the order of auxiliary requests 3 and 4.

VII. Oral proceedings before the board were held on 24 January 2025 in the absence of appellant I.

VIII. Appellant I (patent proprietor) requested in writing that the decision under appeal be set aside and the opposition be rejected, implying that the patent be maintained as granted (main request) or, alternatively, that the patent be maintained in amended form on the basis of the claims of one of

- auxiliary requests 1 to 2 filed with its statement of grounds of appeal,

- auxiliary request 3 filed as auxiliary request 4 with its statement of grounds of appeal,

- auxiliary request 4 filed as auxiliary request 3 with its statement of grounds of appeal.

Appellant II (opponent) requested that the decision under appeal be set aside and that the patent be revoked.

IX. In the following, the parties are referred to as "patent proprietor" and "opponent", respectively.

X. Claim 1 of the patent proprietor's main request (patent as granted) has the following wording (the feature numbering used in the decision under appeal appears in square brackets):

"1. Method of manufacture of an automotive light (4) comprising the steps of:

- [1.1] providing a container body (8) delimited by a first perimetral profile (20),

- [1.2] providing a lenticular body (24), internally delimited by a second perimetral profile (28) and externally by an outer edge (32) corresponding to said second perimetral profile (28),

- [1.3] mutually associating at least partially the respective first and second perimetral profiles (20, 28) of the container body (8) and of the lenticular body (24), the contact surface between said perimetral profiles (20, 28) defining a welding interface (48) which extends along a curve defined by a curvilinear abscissa (S),

- [1.4] providing at least one laser emitting device which emits a light beam or radiation having a characteristic emission spectrum,

characterized in that it comprises the steps of:

- [1.5] providing a plurality of fibres (44) which receive portions of the laser beam from the laser emitting device and direct them towards the welding interface (36) through the lenticular body (24), wherein [1.6] the container body (8) acts as an absorbing element towards the light beam and the lenticular body (24) acts as a transmissive element of the light beam,

- [1.7] providing optical devices (52) for changing the divergence of the portions of laser beams outgoing from the fibres (44), so as to collimate them overall along at least one predetermined optical axis (X-X),

- [1.8] identifying at least one discontinuity (54) on the outer edge (32) of the lenticular body (24),

- [1.9] directing on a critical portion (64) of the welding interface (36) at least a first laser beam (60) emitted by a respective fibre (44) lying on an optical plane (P) incident with said critical portion (64) of the welding interface (36),

- [1.10] wherein said critical portion (64) is the portion of welding interface (36) corresponding, i.e. aligned, in a direction perpendicular to said welding interface (36), with said discontinuity (54),

- [1.11] wherein said discontinuity (54) constitutes a change in the distance (55) between the outer edge (32) and the welding interface (36),

[1.12] wherein the optical plane (P) identifies an angle of orientation (alpha) between 0 and 45 degrees with a plane (T) tangent to the critical portion (64) of the welding interface (36)."

XI. Compared to claim 1 of the patent as granted, claim 1 of auxiliary request 1 has the following additional feature.

"[1.13] wherein said angle of orientation (alpha) is seen in the direction of joining the first perimetral profile (20) and the second perimetral profile (28)."

XII. Compared to claim 1 of the patent as granted, claim 1 of auxiliary request 2 has the following additional features.

"[1.14] wherein in the presence of portions of the lenticular body (24) without discontinuity or change in the distance between the outer edge (32) of the lenticular body (24) and the welding interface (36), there is provided the step of directing at least one laser beam, emitted by a corresponding fibre (44), on a corresponding non critical portion (72) of the welding interface (36),

[1.15] said laser beam having a respective optical axis (Y) lying on a second optical plane (Z) incident with said non critical portion (72) of the welding interface (36),

[1.16] wherein the second optical plane (Z) identifies an angle of orientation (beta) between 46 and 90 degrees with a plane (R) tangent to the non critical portion (72)."

XIII. Compared to claim 1 of the patent as granted, claim 1 of auxiliary request 3 has the following additional features.

"[1.17] wherein said optical devices (52) comprise a negative light guide (76) provided with an input (80) and an output (84), wherein the input (80) is facing said fibres (44) and the output (84) is facing said lenticular body (24), [1.18] wherein, the output (84) of the negative light guide is counter-shaped to the outer edge (32) of the lenticular body (24), so as to form a shaped coupling with the outer edge (32) of the lenticular body (24)"

XIV. Compared to claim 1 of the patent as granted, claim 1 of auxiliary request 4 has the following additional feature.

"[1.19] wherein said discontinuity (54) comprises a concave portion or a convex portion"

XV. The parties' submissions may be summarised as follows.

Main request

- Patent proprietor

The subject-matter of claim 1 as granted was novel over document D2, since document D2 did not disclose features 1.8, 1.9, 1.10, 1.11 and 1.12.

Firstly, features 1.8 to 1.11 were linked to the common concept of discontinuity. The discontinuity mentioned in document D2 was related to the geometry of the external surface only of the lenticular body. The distance between the external surface of the lenticular body and the welding interface had no relevance at all with respect to the declared technical problem of document D2. On the contrary, in the wording of claim 1, the discontinuity had a precise meaning as defined by feature 1.11. It was a feature of the assembly of the lenticular body and the container body as a whole because a change in such a distance varied the energy focusing on the welding interface and could lead to a non-homogeneous irradiation of the weld bead. In other words, a discontinuity of the outer edge according to the teaching of document D2 which did not imply a change in the distance with the welding interface was not a discontinuity according to feature 1.11. Further, document D2 did not disclose the step of identifying a discontinuity by looking both at the outer edge of the lenticular body and the distance between said outer edge and the corresponding welding interface. The shape of the external surface was not monitored or compared with respect to the internal interface. Nor was the distance between the outer edge and the welding interface measured in document D2.

Moreover, document D2 did not disclose feature 1.12. This feature had to be interpreted in the light of the description and the drawings of the contested patent. Figures 11a and 11b of the patent clearly showed the construction of the optical planes P and Z with respect to the planes T and R tangent to the critical portion 64 of the welding interface 36. It followed from the figures that both planes T and plane P were perpendicular to the critical portion. The description clearly distinguished the first angle alpha between planes P and T at critical portions from the second angle beta between planes Z and R at non-critical portions. The solution of document D2 corresponded to the plane arrangement at non-critical portions, not to the arrangement at critical portions taught by the patent. Unlike the opposition division's reasoning, the plane of the interface in the embodiment of Figure 18 of document D2 was not horizontal but inclined. So, even if its reasoning were followed, a plane perpendicular to the plane of interface would be parallel to or coincident with plane P, which meant that the angle alpha between planes P and T would be zero. And if the plane T were considered as horizontal or coplanar to the plane of the interface, the angle between plane T and the optical plane P would be much larger than 45 degrees. In any case, no optical planes were depicted in the schematic figures of document D2 nor were they to be found in the description. Hence, it was not possible to derive directly and unambiguously from document D2 a specific value of the angle claimed in feature 1.12.

- Opponent

The subject-matter of claim 1 as granted was not novel over document D2. The step of identifying the discontinuity did not contribute in any manner to the solving of the technical problem. Consequently, feature 1.8 did not contribute to solving the technical problem underlying the contested patent in any way. Features 1.10, 1.11 and 1.12 merely constituted geometric features; they were not technical features. For a technical understanding and a technical relation, the discontinuity had no relevance for performing feature 1.9. The laser beam must only meet the critical portion, but it did not have to run through the discontinuity. Concerning feature 1.8, in the contested patent the discontinuity was related to the variability of the geometry of the lenticular body itself. It was a change in distance from the outer edge to the welding interface, i.e. the contact surface between the container body and the lenticular body, see feature 1.11. A change in the distance between the welding interface and the outer edge was also disclosed in document D2 by means of the surface discontinuities mentioned in paragraphs [0011] and [0014]. Moreover, in paragraph [0018] of document D2, it was indicated that the coupling surfaces were straight or curved. Hence, also in document D2, discontinuities were disclosed. How these discontinuities were identified was not relevant. Claim 1 did not require that the shape of the external surface was monitored or that there was a step of measuring or comparing. Furthermore, the angle range of feature 1.12 included the value of zero degrees. This meant that plane P was parallel to plane T, see dependent claims 4 to 6 as granted as well as paragraphs [0088] and [0089] of the contested patent. In such a case, the feature was realised by a fibre being arranged directly above the welding interface as shown, for example, in Figure 1 of the contested patent. The fibre did not have to be tilted within the plane. In cases where the angle was not zero degrees, there existed an intersecting line between plane P and plane T which was arranged directly above the welding interface. A fibre arranged directly above the welding interface as shown in Figure 1 of the patent would also comply with this condition. The contested patent explicitly covered the alternative arrangement that the fibres were not changed at all in the presence of a discontinuity. An inclination of the fibres in the plane P and/or T was not required by granted claim 1. Further, there was no requirement that all of the critical portion must be covered by the first laser beam. If, in the embodiment shown in Figure 18 of document D2, the plane T tangent to the critical portion was drawn perpendicular to the welding surface, both the light guide 52 and the fibre 32 would be arranged in the plane T. As a result, the fibre 32 would be arranged in an optical plane identifying an angle of 0° with the plane T, in accordance with feature 1.12.

Auxiliary request 1

- Patent proprietor

Feature 1.13 was based on paragraphs [0058] and [0099] and on Figures 11a and 11b of the application as filed. It was acknowledged that the expression "joining direction" did not have any literal basis. Anyway, according to decision T 372/90, the features for which the skilled person could clearly derive the structure and function from the drawings could be used to define more precisely the subject-matter for which protection was sought. Therefore, the requirements of

Article 123(2) EPC were met.

- Opponent

Paragraph [0058] of the application as filed defined that the assembly of the automotive light comprised the step of joining at least partially to each other the respective first and second perimetral profiles 20, 28. For example, the step was provided for arranging the lenticular body 24 to close the containment housing 12 of the container body 8 so as to join the respective first and second perimetral profiles 20, 28. According to paragraph [0099] of the application as filed, the orientation of the optical plane P with the plane T allowed an optimal irradiation of the critical portion. From these passages, neither a definition of the direction of joining nor of the direction in which the angle of orientation alpha was seen could be concluded. Regarding the disclosure of Figures 11a and 11b of the application as filed, the angle alpha was the angle enclosed between the plane T and the plane P. Thus, it was measured in a plane perpendicular or normal to the optical planes T and P. A definition of a direction of joining could not be concluded from these figures. If at all, the direction of joining would be perpendicular to the welding interface. This direction was, however, arranged in the plane T and, thus, perpendicular to the plane in which the angle alpha was measured in Figures 11a and 11b. Additionally, nowhere in the application as filed the expression "direction of joining" was mentioned. Consequently, the requirements of Article 123(2) EPC were not met.

Auxiliary request 2

- Patent proprietor

Nowhere in document D2 a disclosure could be found of the use of fibres having different inclinations with respect to different (critical and non-critical) portions of the welding interface in order to weld a unique automotive light. Moreover, due to the different and mutually excluding inclinations of the optical plane P, there was no possible ambiguity in the interpretation of the scope of amended claim 1. The subject-matter of claim 1 of auxiliary request 2 was therefore novel over document D2.

- Opponent

With the amendment to claim 1, the welding interface must now have non-critical portions, i.e. portions where no discontinuity was present or, in other words, where the lenticular body had a constant thickness. The second optical plane incident with the non-critical portion could lie at an angle of 90 degrees with a plane tangent to the non-critical portion. Hence, the laser beam could be arranged directly above the welding interface. This corresponded to the intersecting line of planes Z and R in Figure 11b of the patent, which was thus arranged perpendicularly to the welding interface. An inclination of the laser beam within the plane was not defined in the claim or required by any of the other features. Thus, the newly incorporated arrangement in the non-critical portion corresponded to the arrangement of the laser beam in the critical portion, because, in Figure 11b of the patent, planes P and T also had an intersecting line perpendicular to the welding surface. Consequently, it was not decisive that an orientation of a laser beam changed in view of a critical portion or a non-critical portion. Maintaining the arrangement of the laser beams or fibres over the complete welding interface was disclosed in document D2. As shown for example in Figures 13 and 14 of document D2, the fibres were arranged perpendicularly to the welding interface over the complete welding interface. Consequently, the fibres were arranged on the intersecting lines of the claimed planes and, thus, also fulfilled the requirements of the additional features of claim 1 of auxiliary request 2. For the sake of completeness, claim 1 of auxiliary request 2 did not require that a non-critical portion was identified. In conclusion, the subject-matter of claim 1 of auxiliary request 2 was not novel over document D2.

Auxiliary request 3

- Patent proprietor

Despite what was disclosed in paragraph [0085] of document D2, the additional feature 1.18 was not known from that document. In fact, document D2 only related to the possibility to avoid an interference between the negative light guide and the lenticular body. Paragraph [0085] of document D2 clarified that the partial counter-shaping was limited to corresponding portions in proximity or substantially in contact. It followed from paragraph [0099] of the contested patent that the additional feature 1.18 provided a complete counter-shaping. Therefore, the counter-shaping introduced by feature 1.18 was useful in order to allow a complete contact and matching between opposing surfaces in order to use the negative light guide as a presser device, while in document D2 only a partial counter-shaping was provided in order to avoid an interference contact between said opposing surfaces. Typically, the light guide was a metal body while the lenticular body was a glass or plastic one. A partial or incorrect counter-shaping would thus imply a damage on the lenticular body and a rejection of the automotive light. In terms of geometry, feature 1.18 was stricter than the embodiment of paragraph [0085] of document D2. The subject-matter of claim 1 according to auxiliary request 3 was therefore novel over document D2.

- Opponent

In paragraphs [0081] and [0082] of document D2, both alternatives of light guides were mentioned, including a negative light guide. The negative light guide 52 comprised an input 56 and an output 60, wherein the input 56 received light from the fibres and the laser radiation coming from the output 60 was directed through the lenticular body, i.e. the second light guide 64, to the welding interface (cf. paragraphs [0068] and [0072] of document D2). Considering that claim 1 did not exclude that the output of the light guide was partially counter-shaped, it followed from Figures 13 and 14 and paragraph [0085] of document D2 that the output of the negative light guide 52 was counter-shaped to the outer edge of the lenticular body 24 as in feature 1.18. Hence, the subject-matter of claim 1 according to auxiliary request 3 lacked novelty over document D2.

Auxiliary request 4

- Patent proprietor

The additional feature 1.19 was not disclosed, claimed or shown by document D2. The opposition already recognised the novelty of this additional feature in its preliminary opinion set out in the communication accompanying the summons for oral proceedings. The subject-matter of claim 1 according to auxiliary request 4 was therefore novel over document D2.

- Opponent

The additional feature 1.19 was also disclosed by document D2. To this end, document D2 defined curvatures as discontinuities in paragraph [0011] and, thus, convex or concave portions. Such curvatures were also illustrated in each of Figures 12, 14, 16 and 17 of document D2. Hence, the subject-matter of claim 1 according to auxiliary request 4 lacked novelty over document D2.