UPC’s Hamburg Local Division provides guidance on the extent to which a patent may be used as its own “lexicon”

Agfa NV v Gucci & Anors. [UPC_CFI_278/2023] – Hamburg Local Division of the UPC (Klepsch, Schilling, Sarlin) – 30 April 2025

While we await a decision on G1/24 from the EPO’s Enlarged Board of Appeal on claim interpretation, the UPC’s Hamburg Local Division (LD) has provided guidance on the extent to which a patent may be used as its own “lexicon”.  In apparent contrast to the decision of the EPO’s Technical Board of Appeal in T56/21 that there was no legal basis for adapting the description to the granted claims, the LD took the view that there were several passages in the description of the patent-in-suit that “should have been deleted” in the light of the amendments made to the patent during examination.  The LD found that these parts of the description to be inconsistent with the granted claims and, accordingly, could not serve as a basis for a broad interpretation of the claims.

Background

This case concerned Agfa’s patent to the manufacture of decorated natural leather and leather articles by inkjet printing. The patented method involved applying a base coat containing a pigment for providing an “achromatic colour” to the leather, and then inkjet printing a colour image onto the base coat. Agfa sued Gucci, while Gucci counterclaimed for revocation of the patent.

The dispute centred on the interpretation of the meaning of the term “achromatic colour”.  The independent claim of the patent[1] referred to a “base coat containing a pigment for providing an achromatic colour different from black”. There was agreement among the parties that the term “achromatic” referred to the base coat as a whole rather than the pigment per se, and that the “achromatic colour” was a colour different from black. However, there was disagreement as to what constituted an “achromatic colour” beyond the requirement that it was different from black.

The Judgment

As is now the UPC’s established practice, the Hamburg LD emphasised that the terms used in the claims governed claim construction[2].  They were not just the “starting point” for claim construction but the authoritative basis for determining the scope of protection.  Nevertheless, the description and drawings always had to be considered, even when interpreting seemingly clear terms.  Accordingly, in line with UPC Court of Appeal’s approach in Nanostring v 10x Genomics [UPC_CoA_335/2023], the LD confirmed that a patent could be used as its “own lexicon”.

In the case at hand, the LD construed the “achromatic colour” in the light of paragraph [0021], which contained a definition of the achromatic base coat.  This passage indicated that a chromatic colour was any colour in which one particular wavelength predominated. Blue and green were provided as examples of chromatic colours, while white, grey and black were given as examples of achromatic colours.  The latter colours were said to have no dominant hue, meaning that all wavelengths were present in approximately equal amounts within those colours.

The cases for infringement and validity centred on whether ivory could be considered as an “achromatic colour”.  Applying the definition in paragraph [0021] that all wavelengths had to be present in approximately equal amounts, the LD did not consider an ivory base coat to be “achromatic” within the meaning of the claim because the wavelength requirement was not met. In reaching this conclusion, the LD took the view that, although the patent saw e.g., white and grey as achromatic colours, it was clear to a skilled person that not all white and grey tones fulfilled the patent’s definition of achromatic, as some white or grey tones would not have all wavelengths present in approximately equal amounts.

The LD’s construction of “achromatic colour” may have been disappointing to Agfa because parts of the description of its patent described base coats having off-white, pale clay and pale yellow colours.  Notably, paragraph [0029] of the patent mentioned “a base coat containing white pigment and one or more colour pigments to provide e.g., an off-white or pale clay colour”.  Similarly, Example 3 described the base coat having a “pale yellow (clay colour)”.

In the LD’s view, however, those parts of the text did not support Agfa’s contention that all off-white base coats were within the scope of the claim, because the application as originally filed concerned both chromatic and achromatic colours. The reference to chromatic colour, however, was deleted during the course of examination of the application. Accordingly, the LD saw the “off-white”, “pale clay” and “pale yellow” embodiments as no longer falling within the scope of claim 1 as amended, as they did not have wavelengths presented in approximately equal amounts.  As such, the LD simply saw the “off-white”, “pale clay” and “pale yellow” embodiments as inconsistencies with the granted claims that “should have been deleted”. Their inclusion in the description could not override the clear definition given in paragraph [0021] because of the need for legal certainty.

Conclusion

This case highlights the risk of including narrow definitions of terms in patents. Even if a patent contains examples that arguably support a broader interpretation of a claim, patent owners may not be able to rely on these examples to justify a broad interpretation of the claim if a term is defined more narrowly elsewhere in the text. Although the LD in this case took pains to explain that the prosecution history was not taken into account in all aspects, the LD nonetheless took note of the way the claims had been amended during examination. This influenced its conclusion that the broader examples were inconsistencies that “should have been deleted” when adapting the description to the allowed claims.

While we await the Enlarged Board’s decision on G1/24, it remains to be seen what approach the EPO will adopt when interpreting claims. While the Enlarged Board has indicated that it will provide more clarity on the role of the description in interpreting claims, it is not yet clear whether the Enlarged Board will also tackle the issue of adapting the description.  The latter was not a question formally put forward in G1/24.  However, the President of the EPO considered the question of whether adapting the description was mandatory to be important when considering whether claims should be interpreted in the light of the description[3]. This seems in line with the reasoning applied by the LD in this UPC judgment.

[1] EP3388490

[2] in line with Article 69 EPC and its Protocol

[3] See paragraph 87 of the President’s submissions of 7 November 2024 on G1/24

This article was written by Partner and Patent Attorney Hsu Min Chung