In a lecture delivered on November 4 to a class of Osgoode IP students, Lord Justice Jacob of the Court of Appeal for England and Wales provided an expert viewpoint of the ongoing debate revolving around the scope of patent monopolies.
By way of introduction, Lord Justice Jacob pointed to two points of view that have coloured interpretation of patent rights – the suspicious view of patents as an inhibition of trade, and the contrasting view of a patent being a reward for inventors’ efforts. We do not have to look far to see these contrasting views – in the Canadian pharmaceutical marketplace these competing viewpoints are alive and well as innovators and generics constantly square off for a share of various areas of the market.
It is during these squabbles that courts are required to determine a patent’s scope by looking at the claims. Interpretation of these claims, says Lord Justice Jacob, is what is causing problems.
In construing claims, courts around the world have taken one of two approaches. The more restrictive approach is to say that a patentee is completely bound by the language of his claims. If a claim requires two components in an invention to be “screwed” together, a defendant will not infringe if their corresponding two components are “glued,” “stapled,” or “nailed,” etc. The second, more liberal view would say that there is a form of infringement here because, although a defendant is just outside a claim, she has taken the “pith and marrow” of the claimed invention.
The different approaches taken to construing claims has led to outcomes that have differed by jurisdiction. Although article 69 of the European Patent Convention purports to declare a manner for claims construction through its protocol, the result is still a haze of uncertainty. For example, in Germany, the courts regularly view claims as only guidelines when determining the extent of protection of a patent. In the UK Catnic decision (Catnic Components Ltd v Hill & Smith Ltd  RPC 183), the patentee developed a hollow beam as a support mechanism for use in construction. The defendant prepared a similar beam, but argued they did not infringe since their beam was constructed slightly differently and thus did not fall within the exact wording of the claims. The Court there developed the so-called 3-part “Catnic test” in order to find that the defendant infringed.
According to Lord Justice Jacob, this approach has been less than useful and has essentially been displaced. In his view, the only question to be asked in these disputes is what the skilled man would understand the patentee to have meant, in view of what the claimed invention is for.
When it comes to the claim construction of patents we are dealing with a sophisticated art. Patentees define their monopoly through patent claims and need to be careful to do so in a manner that protects all they have invented. But according to Lord Justice Jacob, this protection will only be certain once an approach to claims construction can be agreed upon.