Grimme Landmaschinenfabrik GmbH & Co KG v Scott (t/a Scotts Potato Machinery)

A patent claim must be construed through the eyes of the skilled person, without importing limitations from a preferred embodiment or the drawings. For an apparatus claim, the relevant question is whether the apparatus is capable of operating in the claimed way, not whether it is normally operated in that way. Novelty requires inevitable disclosure of every claimed feature. Obviousness is assessed without hindsight, by identifying the skilled person, common general knowledge, the inventive concept, the differences from the prior art and whether those differences required invention. Commercial success is only a secondary indication in rare and clear cases. An implied threat of infringement proceedings is assessed by its effect on the ordinary recipient.

The claimant alleged infringement of a European patent concerning potato-separating machines and of unregistered design right in separator rollers. The defendant denied infringement, challenged the patent’s validity for lack of novelty, obviousness, insufficiency and added matter, and counterclaimed for unjustified threats and declarations concerning statements made to his customers.

The central issues included the construction of the patent claims, whether the prior art anticipated or rendered them obvious, whether the defendant’s Evolution separator infringed, whether the pleaded roller designs were infringed, and whether correspondence to customers amounted to unjustified threats.

1. Construction. The claims were construed according to what the skilled agricultural-machinery designer would understand the language to mean. The claim was not limited to the precise embodiment shown in the specification. “Amplified forward feed” meant discontinuous forward pushes, at least once per revolution, relative to an even forward feed, capable of being delivered to potatoes in the gusset. The claim required each roller to have an elastically deformable shell. “Lip, rib or like extension” was broad enough to include axially short projections arranged across the roller.
2. Infringement. The Evolution separator was capable of giving potatoes in the gusset an additional forward push and therefore satisfied that feature. It infringed claim 17 where, somewhere in the separating path, it had two counter-rotating pairs of rubber rollers. It did not infringe claim 24 because the plain rollers and ribbed rollers were driven in groups rather than being adjustable individually or by counter-rotating pair. Sale of replacement spiral rollers constituted indirect infringement under section 60(2) where the machine infringed.
3. Validity. Pearson did not anticipate claim 1 because it did not inevitably disclose amplified forward feed, a cylindrical shell part with projecting extensions, or deformable clod rollers. Rollastar did not anticipate the claim but rendered claim 1 obvious because it was sufficiently adjustable to provide the claimed feed and the use of a deformable clod roller was obvious. Claims 17 and 24 remained valid. The attacks based on Dahlmann, Spatz, insufficiency and added matter failed. The court rejected hindsight-driven mosaicing of prior art and held that claim 17 required evidence showing why the skilled person would arrive at all its features.
4. Design right and threats. The relevant design-right date was 1998. The Original Evolution roller was made substantially to the claimant’s design and infringed in the overall configuration and internal compression chambers; the Second roller did not. The customer letters constituted veiled threats. The patent threats were justified, but the design-right threats were unjustified because the letters covered all Evolution roller designs although not all infringed. Declaratory relief concerning corrected statements was refused.

First-instance decision in the Patents Court. No appellate history is stated in the judgment.