EP ‘083 relates to a monopole antenna which is partly shaped as a Space-Filling Curve (‘SFC’), a geometry which allows for the reduction of antenna size or, given a fixed size, the operation at a lower frequency. This is due to the fact that an SFC is large in terms of physical length, but small in terms of the area in which it can be included.
According to the claims of EP ‘083, the (SFC shaped) radiating arm of the antenna must form a closed loop. Xiaomi argues that its antenna does not infringe EP ‘083, as the radiating arm of its antenna is not shaped as a closed loop. Fractus disagrees and argues that the perimeter of Xiaomi’s radiating arm (as opposed to its three-dimensional shape) does indeed form a closed loop as claimed.
In interpreting the claims of EP ‘083, the Provisions Judge applies Article 69(1) EPC and Article 1 of the Protocol. It first considers that according to the literal meaning of the wording of the claims, the 3-d shape of the radiating arm and not the shape of the perimeter of the radiating arm falls within the scope of protection. The Judge finds this literal interpretation of the wording of the claims to be in accordance with the description and drawings. On the one hand, the description gives the example of a monopole antenna in which the radiating arm is shaped as an SFC, while on the other hand, the description also provides the example of a (non-claimed) patch antenna in which the perimeter of the patch antenna is shaped as an SFC. The person skilled in the art, reading the description, would therefore notice a distinction between the claimed monopole antenna and other antenna types. Concerning the former, no reference is made to the perimeter, while concerning the latter, the perimeter is mentioned. Furthermore, the Provisions Judge notes that the description mentions that the ‘SFC geometric principle’ can be applied to all known antennas, including antennas with a perimeter shaped as an SFC. However, the Judge emphasizes that those antennas are not claimed.
Fractus asserts that at the priority date (19 January 2000), monopole antennas with a planar, non-linear shape were known. The person skilled in the art would understand, according to Fractus, that in case the monopole antenna has a planar shape, the shape according to the invention is the shape of the perimeter of the radiating arm. The Provisions Judge holds that Fractus has not substantiated that this was common general knowledge. Fractus’ expert had declared that the bandwidth at which the antenna transmits and receives is related to the length of the radiating arm. According to the Judge, the person skilled in the art would realize that an explanation as suggested by Fractus would lead to other ambiguities. If the perimeter were to be assumed to be the shape of the SFC, EP ‘083 does not make clear at which width or thickness of the radiation arm the shape of the radiation arm itself is no longer relevant, but the shape of the perimeter becomes relevant. The Judge does not agree with Fractus that the person skilled in the art would ‘intuitively’ realise that with regard to an antenna of ‘substantial’ width the perimeter becomes relevant. The Provisions Judge finds that the claimed feature of a ‘closed loop’ would be deemed redundant by the person skilled in the art, if it were to be assumed that EP ‘083 concerned the shape of the perimeter rather than the shape of the radiating arm itself. After all, any perimeter would, by its very nature, form a closed loop.
Finally, the Provisions Judge observes that the skilled person would turn to the prosecution history and find that all parts of the description and drawings referring to a perimeter relate to (types of) antennas that have initially been claimed, but were later removed during prosecution. He would note that the claim, in which specifically the perimeter of the radiating arm of a monopole antenna was proposed, was assessed during examination in appeal by the TBA as lacking clarity and forming added subject-matter. Hence, Fractus withdrew this claim. According to the Judge, these circumstances justify the interpretation of the claims as advocated by Xiaomi. Fractus was denied the requested PI.
This is in line with the pemetrexed decision of the District Court of 19 June 2019, in which the Court also assumed a narrow scope of protection as a result of the patentee restricting a claim during prosecution.