2025 Week 31
This week we look at the recent Nera Innovations v. Xiaomi decision – a case where Non-Practising Entity (NPE) Nera sued Xiaomi for infringement of their wireless energy receiver patent. The decision issued by the Hamburg Local Division highlights several useful takeaways – it’s a good example of how non-bifurcation can help a defendant make “squeeze” arguments, and there’s commentary about how the UPC may treat large numbers of auxiliary requests.
NPE Nera’s case
Nera, an NPE focussed on asserting patent rights without practising the invention, sued Xiaomi, a leading manufacturer of wireless energy receiver devices in smartphones, for infringement of the German and Dutch parts of EP 2642632 B1.
The patent, originally filed by LG and acquired by Nera in 2021, relates to wireless charging devices, and in particular to a wireless power receiving device with a receiving antenna for wireless charging. Claim 1 and Fig. 11 of the patent are provided below (with the key disputed features highlighted in the claim, and colouring added to the figure by Xiaomi):
1. A system comprising a wireless power receiver (1000) and a connecting unit (300), the wireless power receiver (1000) comprising:
a substrate (100) configured to change a direction of a magnetic field received from a transmission side;
a coil unit (200) including a first connection terminal (210), a second connection terminal (220) and a coil (230), wherein the coil (230) is configured to wirelessly receive power, wherein the coil (230) is formed as a conductive pattern on or inside the substrate (100), and wherein the first connection terminal (210) is located at one end of the coil (230) and the second connection terminal (220) is provided at the other end of the coil (230),
characterized in that the substrate (100) has a receiving space formed therein for the connecting unit (300),
wherein the connecting unit (300) includes a first connection terminal (310) of the connecting unit (300) for connecting to the first connection terminal (210) of the coil unit (200) and a second connection terminal (320) of the connecting unit (300) for connecting to the second connection terminal (220) of the coil unit (200).
In the figure below, the substrate is shown in pink, the connecting unit is shown in green, and the coil unit is shown in yellow.
Intermediate generalisation: loss of “magnetic”
One of the key arguments advanced by Xiaomi in their counterclaim for revocation was that granted claim 1 introduced an intermediate generalisation, because, compared to claim 1 of the application as filed, the term “magnetic” had been omitted from the definition of the “substrate configured to change a direction of a magnetic field received from a transmission side”.
The Hamburg Local Division agreed. They found that the skilled person would know that in order to “change a direction of a magnetic field”, the substrate could well be formed from magnetically conductive materials, but that all electrically or magnetically conductive materials have the effect of changing the direction of a magnetic field. As such, “a substrate configured to change a direction of a magnetic field received from a transmission side” could be a magnetic substrate, but this is not necessarily the case – and as such the granted claim is broader than the application as filed.
Fortunately for Nera, an auxiliary request was on file that limited the substrate to being magnetic, addressing this objection.
The squeeze
In order to establish infringement, Nera relied on a broad interpretation of the feature “a receiving space formed therein for the connecting unit”. Their argument was that this didn’t require the receiving space to have exactly the same shape as the connecting unit. They argued that the claim did not specify the size or shape of the receiving space, only that it is suitable for receiving the connecting unit.
However, Xiaomi again counterattacked on added-matter grounds, pointing out that the claimed feature relating to the “receiving space” was broader than in the application as filed in that it merely required “a receiving space formed therein for the connecting unit”, without the restriction in the original claims that the receiving chamber has a predetermined shape that corresponds to a shape of the connecting unit. The court agreed with Xiaomi, finding the omission of this feature to add subject-matter.
To fix this added subject-matter problem, Nera had to fall down to another auxiliary request, and amend the claim to require the receiving space to be of a predetermined shape corresponding to a shape of the connecting unit.
However, this fix had consequences. By amending the claim to address this added subject-matter issue, Nera had amended their claim away from Xiaomi’s products, because none of Xiaomi’s products had a receiving space that corresponds to the shape of the connection unit. The Hamburg Local Division therefore found claim 1 amended in line with Auxiliary Requests 1 and 2 to be valid, but not infringed by Xiaomi’s products.
As such, Xiaomi had orchestrated a successful squeeze argument – if there is infringement, then the patent must be invalid for adding subject-matter. Xiaomi successfully forced Nera into a no-win choice – either keep the broader claim and face invalidity, or amend it and lose infringement. This highlights the strategic benefits of non-bifurcation of UPC proceedings (i.e., the same division hearing infringement and validity together) for defendants of infringement actions, in that a consistent claim interpretation must be used for both infringement and revocation to “squeeze” out of infringing the claim.
Relevance of prior art in different technical field
Another interesting point from this decision is the Hamburg Local Division’s stance on two prior art documents that were in different technical fields to the patent. They questioned the relevance of D5 and D6 – relating to near-field communication of data (e.g., RFID) rather than wireless charging. In particular, the Local Division state in their headnote of the Decision:
If a citation has a comparable function but a different field of application (adjustment of the resonance frequency of antenna device in a receiver for near-field communication) compared to the system claimed (design and manufacture of a power receiver for wireless charging), it is not a document from the state of the art which a person skilled in the art would have consulted in searching for a solution to the problem addressed by the patent in suit, Articles 54 and 56 EPC.
Generally, this aligns with EPO practice in considering inventive step, although the EPO’s assessment is slightly more nuanced – at the EPO, the skilled person may be expected to look for suggestions in neighbouring or even completely remote fields if prompted to do so.
The Local Division’s reasoning in the decision also confirm that it is “not absolutely necessary for a document from the prior art to address the same task as the patent in suit in order to be considered novelty destroying at the UPC” – consistent with EPO standards.
How many auxiliary requests is too many at the UPC?
Another point discussed in this Decision was the number of auxiliary requests on file – two sets of 33 Auxiliary Requests (66 in total). Xiaomi challenged this under Rule 30.1(c) of the RoP which requires that the number of auxiliary requests must be “reasonable in number in the circumstances of the case”.
The court acknowledged that the number of requests in this case was “quite high”, and that “the manageable number of features of the patent in suit and the six citations, which are also within the usual range, do not necessarily suggest such a detailed auxiliary defence of the patent in suit”. However, they also observed that many of the requests simply combined existing requests in different ways, and that the core legal issues remained narrow.
Importantly, the Court praised Nera’s use of a tabular summary showing the claim amendments across auxiliary requests, which made it clear that the number of amendments to be discussed was limited. On that basis, the Court admitted all auxiliary requests into the proceedings. This underscores the importance of presentation of auxiliary requests. A well-organised table of claim amendments can be the difference between being seen as helpful or obstructive by the Court.
Finally, to compare with EPO practice, it’s quite common to see 66 (or more) Auxiliary Requests filed in an EPO opposition. In our recent review of 2024’s most-opposed patents, we found that where the proprietor had already responded to the oppositions, the number of auxiliary requests filed ranged from 0 to 164, with the majority filing between 20 and 60. EPO Opposition Divisions and Board of Appeals also generally welcome the use of tabular summaries to helpfully show the lines of amendment through different combinations of auxiliary requests. Presenting amendments in this structured way can often strengthen arguments that a high number of auxiliary requests is justified and should be admitted into the proceedings.
