The general principles when looking at how the courts interpret any patent can be found at Virgin Atlantic Airways Ltd v Premium Aircraft Interiors UK Ltd  EWCA Civ 1062,  RPC 8 at  Jacob J said as follows:-
“The task for the court is to determine what the person skilled in the art would have understood the patentee to have been using the language of the claim to mean. The principles were summarised by Jacob LJ in Mayne Pharma Pty Ltd v Pharmacia Italia SpA  EWCA Civ 137 and refined by Pumfrey J in Halliburton Energy Services Inc v Smith International (North Sea) Ltd  EWHC 1623 (Pat) following their general approval by the House of Lords in Kirin-Amgen Inc v Hoechst Marion Roussel Ltd  RPC 9”.
(i) Consider Article 69 of the European Patent Convention.
(ii) Article 69 refers to the claims that determines the protection. It goes on to say that the description and drawings shall be used to interpret the claims. Jacon stated “In short the claims are to be construed in context”.
(iii) Claims are to be construed purposively – the inventor’s purpose being ascertained from the description and drawings.
(iv) It further follows that the claims must not be construed as if they stood alone – the drawings and description only being used to resolve any ambiguity. Purpose is vital to the construction of claims.
(v) Both purpose and meaning are different. When the invention is created the inventor may have one, generally more than one, concept. Main thing is to focus on the language – the terms of the claims are the key.Â