Watermark

4 February, 2008
Patent claims must be new and have an inventive step.  Newness is often easy to find, all that is required is that the invention be different from the prior art.  The quality of the difference from the prior art is essentially irrelevant.  Inventive step, on the other hand, assesses whether the patentee’s invention, the patentee’s advance over the prior art, required a contribution beyond the capacity of skilled workers in a particular field.  Inventive step considerations therefore demand an assessment of the level of skill in the field so that the quality of the difference from the prior art can be properly measured.  This assessment may be difficult and expensive since the evidence must be obtained in such a way that it is not contaminated by material that biases the evidence in favour of, or contrary to, a finding of inventive step.  Such objective evidence is often not easy to obtain.

Fortunately, there is a possible solution.  So-called secondary indications of inventive step – facts that demonstrate the quality of an invention without reference to the skill level in the particular field of technology – may be established more readily and less expensively than the state of technical knowledge in the relevant  field.  Courts, including Australian courts, recognize this and weigh such secondary considerations carefully: see, for example, the recently decided High Court case in Lockwood v Doric. What are the secondary indications?  There may be several categories.  Those found most persuasive of inventive step are:

·        Commercial success of the invention.
·        Satisfaction of a long felt but unsolved need.
·        Copying of an invention by competitors.
·        Evidence of difficulty in developing the invention.

Commercial success may be established, for example, by reference to increased sales of a patented product or reduced costs of production.  Often such evidence may be obtained from the patentee’s business records.  Further evidence may be obtained from favourable reviews of the invention in trade literature.  Commercial success may be established in many other ways.

Therefore, it can often be worthwhile considering whether commercial success may be evidenced assisting findings of inventive step in both prosecution and enforcement contexts.  A qualification on this technique for establishing inventive step is that evidence of commercial success may often require revealing commercially sensitive information.  This must be weighed against the commercial value of the patent and difficulty in accessing other sources of proof of inventive step.

Richard Baddeley