Sheep Farming And The Doctrine Of Equivalents

• Published date: 23 May 2020
• Author: Mr Nicolas Fox
• Subject Matter: Intellectual Property, Litigation, Mediation & Arbitration, Patent, Trials & Appeals & Compensation
• Law Firm: Finnegan, Henderson, Farabow, Garrett & Dunner, LLP

Contemplating the Supreme Court Actavis v Lilly¹ decision, and playing around with Word, I was prompted to draw the following two drone's-eyeviews of grazing sheep.

Contemplating the Supreme Court Actavis v Lilly1 decision, and playing around with Word, I was prompted to draw the following two drone's-eyeviews of grazing sheep. As every sheep farmer knows, basically there are two ways you control how sheep graze. You can build a fence (Figure 1), in which case the sheep can eat all the grass in the field. Alternatively you can put a stake in the ground and tie one end of a rope to the stake and the other end of a rope to the sheep in which case the sheep can eat all the grass in the area of a circle centred on the stake (Figure 2).

Patent attorneys may recognise similarities with Article 1 of the Protocol on the Interpretation of Article 69 EPC which states that:

"Article 69 should not be interpreted as meaning that the extent of the protection conferred by a European patent is to be understood as that defined by the strict, literal meaning of the wording used in the claims, the description and drawings being employed only for the purpose of resolving an ambiguity found in the claims. Nor should it be taken to mean that the claims serve only as a guideline and that the actual protection conferred may extend to what, from a consideration of the description and drawings by a person skilled in the art, the patent proprietor has contemplated. On the contrary, it is to be interpreted as defining a position between these extremes which combines a fair protection for the patent proprietor with a reasonable degree of legal certainty for third parties."

The Protocol on Interpretation was a compromise. Prior to 1978, the Continental view was that the UK courts took an overly strict interpretation limiting the scope of protection to the literal wording of the claims. Conversely, the British view, of German "Kerntheorie" was that that the German courts were overly liberal using the claims merely to identify a "stake in the ground" of an inventive concept. The Protocol on Interpretation clearly states that neither such approach is correct.

The Protocol on Interpretation establishes that the scope of protection is neither limited to a strict literal interpretation of the wording of the claims (the fence post approach in Figure 1), nor are the claims used simply to define an inventive concept (the stake and rope approach of Figure 2). Rather, staying with the sheep...