No. 134 - June 9, 2026

Milan Local Division on patent literature as common general knowledge and evidentiary asymmetry

Timan Pfrang
Tilman Pfrang, LL.M.
Patent Attorney, Dipl.-Phys.

Milan Local Division on patent literature as common general knowledge and evidentiary asymmetry in infringement proceedings where the defendant controls the relevant information

Pirelli Tyre S.p.A. v Sichuan Yuanxing Rubber Co., Ltd. — Local Division Milan, 26 May 2026, UPC_CFI_770/2024, UPC_CFI_556/2025

Introduction

In this decision, the Milan Local Division addressed two noteworthy issues extending beyond the specific infringement dispute between the parties.

First, the Court considered under what circumstances patent literature may form part of the common general knowledge of the skilled person. Aligning itself with established EPO Boards of Appeal case law, the Court confirmed that patent documents will only exceptionally qualify as common general knowledge, but accepted such an exception on the facts of the case.

Secondly, and perhaps of broader practical significance for UPC infringement litigation, the Court addressed evidentiary asymmetry in infringement proceedings and confirmed that evidentiary burdens may be redistributed where the claimant provides sufficiently strong indicia of infringement while the defendant has privileged access to the relevant technical information.

The headnotes in English translation

  1. The Court shares the interpretative approach expressed by the EPO Boards of Appeal (see Decision T 1000/12 of 17 December 2013, T 412/09 of 9 May 2012 et al.), according to which it is only in exceptional circumstances that patent literature may be presumed to represent the common general knowledge of the skilled person. Such exceptional circumstances arise, for example, where a series of patent documents provides a coherent picture showing that a particular technical procedure is generally known. In the present case, there is evidence of the existence of a series of patent documents closely relating to the specific field of tyres, in which the same technique of planar representation of the tread pattern is adopted, such that it therefore represents the common general knowledge of the skilled person.
  2. The principle of proximity of evidence permits a redistribution of the burden of proof where the party bearing the burden of proof has provided strong indicia in relation to the fact to be proven (here: the patent proprietor by means of photographic reproductions of the defendant’s products), and the opposing party (here: the defendant accused of patent infringement) has privileged access to the documents and information that make it possible to establish that fact directly. The Court of Justice focused attention on this point in cases where the refusal of the defendant to provide information in its direct possession may compromise the effectiveness of the evidentiary regime, requiring the national court to assess the informational asymmetry between the parties (see judgment of 21 July 2011, Kelly, C-104/10, paras. 38 et seq.).

Patent literature and common general knowledge

The Court expressly endorsed the EPO Boards of Appeal’s established approach that patent literature normally does not form part of the common general knowledge of the skilled person.

Referring to decisions T 1000/12 and T 412/09, the Milan Local Division confirmed that only exceptional circumstances justify treating patent documents as reflecting common general knowledge.

Such circumstances may exist where a consistent body of patent literature demonstrates that a particular technical approach was generally known in the relevant field.

The Court found such an exceptional situation here. The relevant technical issue concerned the planar representation of tyre tread patterns. In the Court’s view, a sufficiently coherent series of patent documents from the specific tyre sector demonstrated that this representation technique formed part of the common general knowledge of the skilled person.

Evidentiary asymmetry and burden of proof

Another significant aspect of the decision concerns proof of infringement.

The claimant relied, inter alia, on photographic reproductions of the defendant’s products, including materials obtained at the EICMA trade fair, to establish infringement. The defendant challenged the evidentiary value of that material. The Court rejected a purely formalistic allocation of evidentiary burdens.

Relying on the principle of proximity of evidence, the Milan Local Division held that where the party bearing the burden of proof has presented strong indicia supporting the alleged facts, and the opposing party has direct access to the relevant information and evidence, evidentiary burdens may be redistributed accordingly.

The Court expressly referred to the CJEU’s judgment in Kelly (C-104/10), noting that refusal by a defendant to provide information within its direct possession may undermine the effectiveness of evidentiary rules and requires courts to take account of informational asymmetry between the parties.

This is a potentially important statement for UPC infringement litigation. Patent proprietors will often face practical limitations in obtaining direct technical evidence regarding allegedly infringing products, particularly where relevant details lie within the defendant’s internal documentation or technical sphere.

The decision suggests that the UPC may be prepared to respond pragmatically where claimants provide persuasive circumstantial evidence rather than requiring unattainable direct proof.
At the same time, the threshold remains that you need strong indicia before any redistribution of evidentiary burdens becomes justified.
 

Takeaways

  • The Milan Local Division confirms that patent literature forms part of the common general knowledge only exceptionally, but such exceptions may exist where a coherent body of patent documents demonstrates a generally known technical approach.
  • Where a claimant provides strong indicia of infringement and the defendant controls the relevant technical information, evidentiary burdens may be redistributed.