A guide to the UPC and the UP - Flipbook - Page 170
– Would it be recognised by the person skilled in the relevant art?
– Would that person focus[sing] on the essential meaning of the technical teaching protected
in the patent regard the variant as being equivalent to the solution offered by the invention?
10-98 There are similarities between these three questions but also some potentially significant
differences and the Court is going to have to reconcile these at a fairly early stage.
File Wrapper Estoppel
10-99 An issue often closely related to protection of equivalents is the ability of a party to rely on
statements made by the patentee during the patent’s prosecution as evidence relating to
the scope of protection of a claim, commonly known as “prosecution history estoppel” or
“file wrapper estoppel”. National courts have again taken a variety of different approaches to
this issue. For example, the German Federal Patent Court (Bundesgerichtshof) has held that:
“it is permissible … to use statements made by the applicant [and the examiner] during the
grant procedure as an indication of how the person skilled in the art understands the subject
matter of the patent”
but “such indications cannot be readily used as the sole basis for construction”. 70 The Dutch
Supreme Court has also held that:
“a court will only be justified in using clarifying information from the public part of the granting
file, when it holds that even after the average person skilled in the art has considered the
description and the drawings, it is still open to question how the contents of the claims must
be interpreted”. 71
These approaches are often contrasted with the approach of French courts which are said
to be more ready to refer to the prosecution history to settle issues of claim interpretation.
Despite historical reluctance to consider the prosecution history, courts in the UK have recently
moved closer to the German and Dutch approaches by discouraging, but not forbidding
entirely, reference to the prosecution file when considering questions of claim interpretation. 72
In particular, the UK Supreme Court has recently outlined the two circumstances in which it
believes it would be permissible to refer to the prosecution file:
“(i) the point at issue is truly unclear if one confines oneself to the specification and claims of
the patent, and the contents of the file unambiguously resolve the point; or (ii) it would be
contrary to the public interest for the contents of the file to be ignored.”
10-100 As with equivalents, it will again be interesting to see how the Court will address this issue
when it first arises, especially given the recent move by the UK courts towards the German
and Dutch approach.
70
71
72
Eli Lilly v Actavis Group PTC, Case No X ZR 29/15.
Ciba-Geigy AG v Oté Optics BV (1995) 28 IIC 748.
Actavis UK Limited v Eli Lilly [2017] UKSC 48 at [87].
© Bird & Bird LLP | May 2023
A Guide to the UPC and the UP 160
