Environmental Defence Systems Ltd v Synergy Health Plc & Ors

For inventive step, the skilled person may differ according to the task being performed. Obviousness through the eyes of either a person drawn from the prior art field or a person drawn from the invention’s technical field is fatal. The court must not combine those perspectives into a composite skilled person. In the IPEC, the defendant must identify the skilled person’s technical field in its pleading, so that the parties’ expert evidence can be controlled at the case management conference. An invention lacks an inventive step where the skilled person would regard the claimed use of known technology as worth trying with a reasonable expectation of success. Arranging absorbent pads in a barrage bag or sack was an obvious implementation of the known concept.

The claimant owned a patent for a method of manufacturing barrage units used for flood defence. The defendants challenged validity on the ground that the claimed methods lacked an inventive step. The trial was confined to a preliminary issue concerning whether there was an inventive step in using the known method of manufacturing absorbent pads to make barrage units.

The dispute focused on claims 1, 6 and 9. Claim 1 concerned using the absorbent-pad manufacturing method in a barrage unit. Claim 9 concerned arranging the pads within a porous bag or sack. The central questions were the appropriate technical field of the skilled person, the relevant common general knowledge, and whether the claimed uses were obvious.

1. Skilled person. The characteristics of the skilled person used for claim construction or insufficiency may differ from those used for inventive step. Under Schlumberger Holdings Limited v Electromagnetic Geoservices AS [2010] EWCA Civ 819, [2010] RPC 23, a skilled person drawn from the field of the prior art and a skilled person drawn from the technical field of the alleged invention may each be used. Obviousness through the eyes of either is fatal. It is impermissible to combine their perspectives into a composite skilled person.
2. IPEC procedure. A defendant attacking validity must nominate in its pleading the technical field from which the inventive-step skilled person is drawn and outline its inventive-step case in accordance with Pozzoli SpA v BDMO SA [2007] EWCA Civ 588, [2007] FSR 37. The patentee should respond concisely. By the case management conference, the parties’ positions and the disciplines relevant to expert evidence should be clear. Expert evidence remains subject to the cost-benefit control in PD 63 paragraph 29.2(2).
3. Common general knowledge. Following Generics (UK) Ltd v Daiichi Pharmaceutical Co Ltd [2009] RPC 23, common general knowledge comprises basic reliable information in the relevant field, whether remembered or known to exist and readily accessible. Experts explain published knowledge, its dissemination and its likely significance; the court determines what formed part of the common general knowledge.
4. Claims 1 and 9. The skilled person in the flood-defence field would have known that barrage units could be made using absorbent polymer. The known absorbent pads, containing absorbent polymer and fibrous material, would have been worth trying as fillers with a reasonable expectation of success. Claim 1 therefore lacked an inventive step. Arranging the pads within the bag or sack, including in a non-jumbled arrangement to improve effectiveness, was also obvious. There was no inventive step in claims 1, 6 or 9. The preliminary issue was determined against the claimant.