Fleur Tehrani v Hamilton Bonaduz AG & Ors.
Decision date: 22 December 2021
Neutral citation: [2021] EWHC 3457 (IPEC)
Overall AI summary confidence: high
Short overview
This short overview is intended to summarise the case, issues and outcome so far as they are supported by the judgment.
AI confidence in this short overview: high
This case concerned validity and infringement of a ventilator control patent (priority 21 Nov 2003) asserting automated determination of FiO and PEEP for "a next breath" to keep PEEP/FiO within a prescribed range (claim 1) and an extended claim 45 using CO2 and lung mechanics. The judge found the patent invalid overall: claim 1 would have been infringed by the defendant's Intellivent‑ASV but lacked novelty over Waisel, and claim 45 was not infringed and was obvious over Waisel. Hamilton's revocation counterclaim succeeded.
Ratio decidendi
This summary is intended to identify the ratio decidendi, meaning the legal reasons for deciding and the binding part of the decision.
AI confidence in this ratio decidendi summary: high
The judge took a contextual approach to construction: "a next breath" can mean the immediately following breath or a later breath depending on clinical/technical context, so claim 1 covers determinations made at various intervals; and wording that FiO and PEEP are "determined to keep a ratio within a prescribed range" does not compel an explicit arithmetic calculation of the PEEP/FiO ratio because maintenance can be achieved by preset paired values or by calculation. Applying these constructions, the prior art (notably Waisel) anticipated claim 1 and made claim 45 obvious.
Obiter dicta
This summary is intended to identify obiter dicta, meaning observations made by the way that were not necessary to deciding the case and are not binding.
AI confidence in this obiter dicta summary: medium
The judgment expressed views on the weight to be given to expert evidence where the expert is also an inventor—demeanour and cross‑examination responses affect reliability—and commented that distinctions between protocol‑driven or trial‑and‑error systems and continuous closed‑loop systems should be supported by clear technical explanation.