Patent infringement: The perils of a poorly pleaded defence

In No Climb Products Limited v Gas Safe Europe Limited [2026] EWHC 908 (IPEC), the Court held that No Climb Products Limited’s European Patent (UK) No. 2 265 516 B1 was valid and infringed by Gas Safe Europe Limited’s DetectaReach and DetectaSmoke products. Gas Safe Europe Limited was unsuccessful in its attempt to narrow the definition of the skilled person, misinterpreted the patent, failed to disclose evidence, and was defeated in its validity challenges which ultimately led to judgment in favour of No Climb Products Limited.

No Climb Products Limited (the Claimant) is the owner of European Patent (UK) No. 2 265 516 B1 – ‘Testing apparatus for testing a gas or smoke detector controlling the distance between an aerosol dispenser and the detector’ (the Patent). Gas Safe Europe Limited (the Defendant) sells a device referred to as the DetectaReach as well as a replacement aerosol can for the DetectaReach, known as the DetectaSmoke. The Claimant alleged that both products infringe the Patent.

Person Skilled in the Art

Initially, it was agreed that the person skilled in the art is a designer of testing apparatus for smoke and/or gas detectors with some years’ experience of working in that field. The Defendant sought to narrow the scope further, arguing that this person would also have experience of making plastic components such as its own products. However, the Defendant’s first misstep in this claim was its failure to provide sufficient evidence in support of this argument. Consequently, the Defendant conceded an opportunity to argue that the invention which is the subject of the Patent would be obvious to a person with a more specialised skillset.

Construction of the Patent

The Defendant then went on to misinterpret aspects of the Patent, including whether or not the spacer must be permanently fixed to the container. The Defendant erroneously sought to rely on two particular paragraphs in the description, one of which discusses the prior art rather than the invention itself, and the other which sets out the preferred embodiments rather than a definition of the invention of claim 1.

Defence to Infringement

The Claimant argued that the marketing of the Defendant’s DetectaSmoke product infringes the Patent under section 60(2) of the Patents Act 1977 (the Act), and the judgment contains a helpful reminder of the requirements of this subsection as set out in Jeff Gosling Limited v Autochair Limited [2025] EWHC 1687 (IPEC).

The Defendant failed to establish a defence due to a failure to provide disclosure despite having been given an order to do so. Subsequently, the Defendant sought to rely on a defence pursuant to section 60(3) of the Act. The Defendant argued that, if a product cannot infringe under section 60(1) of the Act because it forms part of the prior art, then it must be a staple commercial product. The Court was unpersuaded by this argument.

The Validity of the Patent

The Defendant was unsuccessful in its attempt to argue that the Patent lacks novelty and inventive step over three existing patents. Ultimately, the Court held that the Patent is valid and the Defendant’s products infringe claims 1, 8 and 9.

Key takeaway

The key takeaway is that poorly applied arguments can result in parties inadvertently narrowing their own defence and paving the way for a claimant to obtain judgment in its favour. This judgment serves as an important reminder for defendants to ensure their arguments are sufficiently supported with relevant evidence in order to ensure that a claim is not lost due to a poorly pleaded case. The team at Walker Morris is well placed to support you at every stage of a dispute. If you are involved in a dispute, please do get in touch.