Ferag AG v Muller Martini Ltd

A patent claim must be construed purposively through the skilled reader’s understanding of the invention. A requirement that a knife part is associated with a printed product may require allocation of that knife part to the product, rather than physical contact before cutting. Where the claim requires substantially the same velocity and engagement along a cutting edge, those requirements may be satisfied during the cutting period alone.

For anticipation, prior art must disclose an arrangement which, if performed, must infringe the claim and must enable it. Permissible trial and error in enablement cannot alter the prior disclosure to supply a missing integer. Obviousness must be assessed without hindsight. A court must identify the differences from the prior art and decide whether the skilled person had a reason to make the required changes.

Ferag alleged that Müller Martini’s NewsTrim machine infringed its European patent for continuously trimming multilayer printed products. The machine used a fixed knife part and rotating knife parts, while a separate clamp conveyed each printed product.

Lewison J held that the NewsTrim fell outside the process claims, that the patent was invalid over Stobb for obviousness, and that a proposed amendment could not save it. Ferag appealed with permission. Müller Martini supported the result and contended that, if the claim covered the NewsTrim, Rösner anticipated it.

The central issues were the purposive construction of claim 1, infringement, anticipation, and whether adapting the Stobb proposal would have been obvious.

1. Appeal allowed. The court held that unamended claim 1 was valid and infringed. Tuckey and Mummery LJJ agreed with Jacob LJ.

2. On a purposive construction, the claim’s requirement that a first knife part is jointly associated with a product means that the knife part is allocated to the particular product or group which it is to cut. It does not require physical contact before cutting. The association continues until after the cut. The knife part and product must have substantially the same velocity, and be engaged along a cutting edge, during the cutting period. Claim 1 does not require the first knife part itself to convey the product; that additional limitation appears in claim 3.

3. The NewsTrim met those requirements. Before cutting, a rotating knife part was associated with the product. At the cutting point it and the product moved at substantially the same velocity and entered cutting engagement with the fixed knife part. Its rotating knives did not form fixed pairwise knife-counterknife units of the conventional kind described in the patent. The judge therefore erred in finding no infringement.

4. Stobb did not anticipate. Its actual disclosure was a single-knife system, not a two-knife shear-cutting system. Converting the adjustable clamp into a counterknife with the necessary clearances would depart from what Stobb disclosed. That might bear on obviousness, but could not supply the missing disclosure for novelty. Stobb also produced U-shaped trimmings rather than the end-to-end shear cuts contemplated by claim 1.

5. The claim was not obvious over Stobb. Stobb addressed a slower operation and gave no practical solution to the high-speed trimming problem. It offered an unattractive single-knife proposal and required numerous changes to reach the claim. The proposed modified models illustrated hindsight rather than routine workshop development. Rösner also did not anticipate because its book block and lower knife did not move past the upper knife in order to bring the knife parts into cutting engagement.

• Court of Appeal (Civil Division): allowed Ferag’s appeal and held the patent valid and infringed: [2007] EWCA Civ 15.
• Chancery Division, Patents Court: Lewison J held that the NewsTrim did not infringe, that the patent was invalid for obviousness, and that the proposed amendment could not save it: [2006] EWHC 225 (Ch). Those conclusions were reversed.