E Mishan & Sons, Inc (t/a Emson) v Hozelock Ltd & Ors

For patent infringement, the court must first construe the claim purposively and then consider whether a variant is nevertheless an immaterial variation under the three Actavis questions. A claim limitation may be construed in the context of the specification, including its description and drawings.

For an expandable hose, “non-elastic” meant substantially less elastic than the elastic inner tube, rather than perfectly inelastic. A prior use is relevant only if information about the invention was made available to the public. A private activity visible from a public place may fail to qualify where, as a matter of fact, observation would have caused the inventor to stop the activity.

The claimant was the exclusive UK sub-licensee of patents GB 2 490 276 and EP (UK) 2 657 585 for expandable garden hoses. It alleged that Hozelock’s Superhoze 1 and Superhoze 2 infringed the patents. Hozelock denied infringement and challenged validity for lack of inventive step over Ragner, McDonald and alleged prior use in the inventor’s garden. Priority was also disputed in relation to claim 1 of EP 585.

The central issues were the construction of “coupler”, “unattached” and “non-elastic”; infringement under the doctrine of equivalents; whether the garden activities constituted prior use; obviousness; and priority.

1. Infringement approach. Following Actavis UK Ltd v Eli Lilly & Co [2017] UKSC 48 and Icescape Ltd v Ice-world International BV [2018] EWCA Civ 2219, infringement required consideration of normal interpretation followed by the three reformulated Improver questions. The claims had to be construed purposively in context, applying Wood v Capita Insurance Services Ltd [2017] UKSC 24.
2. Construction. “Coupler” referred to a component enabling the hose to connect to another hose, a tap or a fitting. It did not mean a component joining the inner and outer tubes. The Superhozes were therefore not “unattached” on normal interpretation. “Non-elastic” meant very much less elastic than the inner tube. Superhoze 2 satisfied that requirement.
3. Equivalents. The attachments at the Superhoze joiners were immaterial variations. The hoses achieved substantially the same result in substantially the same way; it would have been obvious to the skilled person that they did so; and strict compliance with the wording was not an essential requirement. Both Superhozes would therefore have infringed the relevant claims if the patents were valid.
4. Prior use. The activities visible from the public road did not disclose the invention sufficiently. The skilled observer would not have understood all the relevant features, and the activities on different days could not be mosaiced. Further, the information was not made available to the public under sections 2(2) and 3 of the Patents Act 1977, because the inventor would have stopped or concealed the work if anyone had tried to observe it.
5. Obviousness. Applying the Pozzoli SpA v BDMO SA [2007] EWCA Civ 588 structured approach, the claims were not obvious over Ragner. McDonald, however, disclosed the essential expandable two-tube structure, and adapting it from an oxygen hose to a garden water hose required no inventive step. The patents were consequently invalid for lack of inventive step.
6. Priority. The first priority document disclosed the subject matter of claim 1 of EP 585 directly and unambiguously when read as a whole, including its claims. The priority attack failed. The court declined to decide the proposed Formstein defence because it made no difference to the outcome.