Friday, 2 August 2013

How to read a Patent

Intellectual Property Office, Concept House, Newport
Crown copyright
Reproduced with the permission of the IPO

Updated 9 Oct 2015

Jane Lambert

As I have remarked elsewhere, an inventor makes a bargain with the public when he or she applies for a patent for his or her invention. In exchange for a monopoly of the invention the inventor must disclose the invention in a manner which is clear enough and complete enough for the invention to be performed by a person skilled in the art (s.14 (3) of the Patents Act 1977). If the inventor fails to do that, any patent that may be granted can be revoked under s.72 (1) (c) of the Act.

The document in which the invention is disclosed is known as "the specification". It is one of the documents that must be filed when applying for a patent (see s. 14 (2) (b)).  A specification must contain "a description of the invention, a claim or claims and any drawing referred to in the description or any claim".   According to s.14 (5) (a) the claims "define the matter for which the applicant seeks protection". S.125 (1) of the Act adds:
"For the purposes of this Act an invention for a patent for which an application has been made or for which a patent has been granted shall, unless the context otherwise requires, be taken to be that specified in a claim of the specification of the application or patent, as the case may be, as interpreted by the description and any drawings contained in that specification, and the extent of the protection conferred by a patent or application for a patent shall be determined accordingly."
Claims are therefore enormously important.   It is the claims that we consult when we consider whether a patent has been infringed or whether it is valid.   Usually there are several claims arranged  in numbered paragraphs. Each claim sets out the "features" (also known as "the integers" or "elements") of the invention.   The first claim expresses the invention in the broadest possible terms, the next slightly more narrowly, the third more narrowly still and so on like a set of Russian dolls.

Until the arrival of the internet patent specifications were available only in print.   The only way to read them was to subscribe to the Patents and Designs Journal and buy any specification that was of interest or to visit a the Patent Office or other library that subscribed to the Patent Office's publications.  Nowadays specifications are published on line and can be searched on Espacenet or a number of other online databases.   Specifications are read for the technical information that they contain, for determining the scope of a patent, for finding matter that invalidates a later patent or patent application and many other reasons.

When reading a specification it is important to remember that it is addressed to the "person skilled in the art" that I mentioned in the first paragraph.  A specification uses that person's terminology and assumes that the reader shares that person's skills and knowledge. Generally words are given their everyday meaning but if a word or phrase has a special meaning in the relevant industry then that meaning will apply.

When interpreting claims s.125 (3) of the Patents Act 1977 provides the following guidance:
"The Protocol on the Interpretation of Article 69 of the European Patent Convention (which Article contains a provision corresponding to subsection (1) above) shall, as for the time being in force, apply for the purposes of subsection (1) above as it applies for the purposes of that Article."
In other words, patents granted for the UK by the IPO in Newport have to be interpreted the same way as European patents granted by the European Patent Office ("EPO") in Munich.

The Protocol, which was revised a few years ago, now consists of two articles.  For present purposes, it is enough to concentrate on art 1. When you see the reference to art 69, think of s.125 (1) of the Patents Act 1977 which is quoted above:
"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."
There is a massive amount of case law from courts and tribunals across Europe as to how this provision is to to be applied.   For those who are keen to find out what they are, the latest cases are Kirin-Amgen Inc and others v Hoechst Marion Roussel Ltd and others [2005] RPC 9, [2004] UKHL 46, [2005] 1 All ER 667, (2005) 28(7) IPD 28049, [2005] RPC 169 and Virgin Atlantic Airways Ltd v Premium Aircraft Interiors UK Ltd [2009] EWCA Civ 1062, [2010] RPC 8.

For a practical example of how patents are interpreted read my article "Construction of Patents - Lizzanno Partitions (UK) Ltd v Interiors Manufacturing Ltd".  If you are new to patents you may like to download my  "Introduction to Patents" presentation that I gave to Liverpool Inventors Club on the 29 April and pages 3 to 8 if my handout.    You can also register for my Introduction to Technology Law seminar at 4-5 Gray's Inn Square on 27 Nov 2013 where we shall discuss patents as well as other ways of protecting investments in R & D such as trade secrets, design rights, plant varieties and so on.

If you want to discuss this article or indeed patents or intellectual property in general, call me on 020 7404 5252 during office hours or fill in my contact form.

Oh and one final tip.   Patents in this country are pronounced with a short "a" as in black. Never as "pay tents".  I have heard BBC announcers and even solicitors use the long "a" but it is a real newbie giveaway.

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