Inventive step — not obvious
A quick recap: to be patentable, the invention must be new. Surely, you might wonder, if it is new it is an invention? This is not so, unfortunately.
The enquiry here is not whether it is an invention, but whether the invention you have come up with is an obvious step forward. If people involved in the particular field would say that it is just obvious, then it does not qualify for patent protection. This can result in a lot of evidence and debate in court, with everyone giving their views as to whether your invention would be obvious to someone skilled in the art.
Technically, an invention is considered to involve an inventive step if it is not obvious to a person skilled in the art, having regard to the state of the art immediately before the claimed priority date for the invention. In considering the inventive step, patents lying open for public inspection and inventions used secretly on a commercial scale are excluded from the state of the art.
Read section 25(10) of the Patents Act.
What is meant by an invention being obvious to a person skilled in the art?
As far as the Concise Oxford Dictionary is concerned, obvious means ‘easily perceived or understood’, and ‘predictable’. The definition is close to the meaning given in patent law, but there is more.
First, a reasonably practical way of measuring this ‘obviousness’ is to enquire whether there is a difference between the claimed invention and the prior art. If there is no difference, it is simple: there is no inventive step. If there is a difference, but it is one that did not call for inventive ingenuity, then it is obvious. To illustrate, we’ll use our Kreepy Krauly example.
Let’s accept that the state of the art on automatic pool cleaners, at that time, is summarised in the main claim of the Kreepy Krauly patent (we see this in The procedure for registration) and where it is noted that the apparatus has one cleaning head. I develop a cleaner that has two heads, both doing the same thing. That is a step forward on the art, because an automatic pool cleaner with two heads does not yet exist. However, there is no inventive ingenuity at all. My invention has not added anything to the world of automated pool cleaners.
On the other hand, if the additional head contains a rotating brush connected to gears driven by an impellor in the water flow, which scrubs off algae for the other head to suck up, that may well be inventive.
The person whose frame of reference is taken into account in determining the question of obviousness is someone skilled in the art. This is the ordinary skilled or qualified person in the particular field. If the patent is for a biochemical pesticide, then chemical engineers and biochemists are the experts whose opinion will count. If the invention is a particular feature of a new type of rock-crushing equipment for underground mining, then mining engineers and mechanical design engineers must give their views on whether the feature has inventive ingenuity.