Maccaferri Ltd. v Hesco Bastion Ltd.

Factual and Procedural Background

This appeal concerns a patent infringement dispute between Company A (Appellant) and Company B (Appellee) regarding a patent for a wire mesh cage structure used in building and engineering works, commonly known as a gabion. The patent in question, granted in 1995, relates to a wire mesh structure that can be transported in a folded form and unfolded on site to form connected cavities for filling with building materials. Company A was found by the Patents County Court to have infringed claim 1 of Company B's patent with its product called Flex-Mac. Company A appeals against this finding, challenging both the construction of the patent claim and its validity on grounds of obviousness based on prior art.

Legal Issues Presented

1. Whether, on a proper construction of claim 1 of the patent, Company A has infringed it by importing and selling the Flex-Mac wire mesh cage structure in the United Kingdom;
2. If the claim is construed to encompass the Flex-Mac structure, whether the claim is invalid due to obviousness in light of prior art disclosed in the Czinki patent (EP O 202 552).

Arguments of the Parties

Appellant's Arguments

• Claim 1 should be narrowly construed, emphasizing the concertina folding mechanism as requiring a specific zigzag fold akin to a musical concertina, which Flex-Mac does not replicate.
• Flex-Mac differs geometrically and functionally from the patented structure, notably having single side panels per cavity instead of multiple, not folding face to face as required, and requiring a two-stage unfolding process rather than a single step.
• On validity, if the claim is broad enough to cover Flex-Mac, it is obvious in light of the prior art Czinki patent and common general knowledge, which disclosed similar expandable cage structures and folding mechanisms.

Appellee's Arguments

• The claim should be given a broad, purposive construction consistent with the specification and drawings, where "folded concertina fashion" means any broadly zigzag folding, not a specific bellows-type fold.
• Flex-Mac infringes claim 1 as it meets the essential features, including being foldable flat, transportable, and erectable on site by unfolding without further fixing.
• The differences pointed out by the Appellant are immaterial variants under established patent law principles and do not avoid infringement.
• The patent is valid as the prior art Czinki does not disclose multi-cavity hinged gabion structures of the kind claimed, and the invention involves an inventive step in providing rapid erection without additional fixing on site.

Table of Precedents Cited

Court's Reasoning and Analysis

The court first undertook a detailed construction of claim 1 of the patent, focusing on the meaning of "folded concertina fashion" and the mechanism of unfolding. It concluded that the claim should be given a broad purposive construction consistent with the specification, interpreting "concertina fashion" as a general zigzag folding rather than a narrowly defined bellows-like fold. The court agreed with the trial judge that the claim's essence was the rapid erection of a multi-cavity cage on site by unfolding without further fixing, not the precise folding or opening sequence.

On infringement, the court found that Company A's Flex-Mac product met the essential features of the claim despite minor differences, such as requiring an additional skewing movement to open cavities. Applying the three-step Improver test, the court held that this two-stage unfolding was an immaterial variant and did not avoid infringement.

Regarding validity, the court adopted the four-step Windsurfing test to assess obviousness. It accepted the trial judge's identification of the inventive concept narrowly by reference to claim 1's essential elements. The court found that the prior art, including the Czinki patent, did not render the claim obvious because Czinki concerned a single cavity structure for noise reduction rather than multi-cavity gabions for engineering use, and there was no evidence that the skilled person would have combined these teachings without hindsight.

The court emphasized the need to avoid hindsight and upheld the trial judge's factual findings on common general knowledge and differences from the prior art. It concluded that the patent was valid and infringed.

Holding and Implications

The court DISMISSED the appeal, upholding the trial judge's findings that claim 1 of Company B's patent is valid and that Company A's Flex-Mac product infringes it.

The direct effect is to affirm the patent's protection and Company B's entitlement to enforce it against Company A's infringing product. The decision does not establish new legal precedent but reinforces established principles on patent claim construction, infringement analysis including variants, and the assessment of inventive step in light of prior art.