Re-patenting the prior art - How to avoid re-inventing the wheel!

• Published date: 12 April 2022
• Subject Matter: Intellectual Property, Patent
• Law Firm: Spruson & Ferguson
• Author: Dr. Mike Zammit

It is, unfortunately, a relatively common occurrence to find patent applications filed in which the inventor has discovered some unique characteristic or property of, say, a "new" composition they have prepared, and which they believe is worthy of patent protection, only to later find that the purported invention is not novel or inventive. In particular, experiments are undertaken which yield surprising, unforeseen, or counterintuitive results to the inventor, who then prepares and files a patent application with much enthusiasm, only to later find that the invention is new and surprising to them, and that another researcher has traversed the same research path and already published the invention. To avoid this situation occurring, it is obviously preferable to conduct a reasonably thorough assessment of the prior art before embarking on new research.

In the following, we set out some other matters to be aware of to avoid preparing and filing patent applications that might potentially attempt to re-patent the prior art, thereby wasting significant time, effort, and resources.

An implicit disclosure in the prior art?

The test for novelty in Australia is the "reverse infringement test", which asks the question "whether the [prior art] would, if the [claims of the] patent were valid, constitute an infringement [of those claims]."¹Put simply, if the prior art has "each and every one of the essential integers"² of a claim, then the claim lacks novelty. To assess whether a prior art reference discloses each of the essential features of a claimed invention, it must "be interpreted as at the date of its publication, having regard to the relevant surrounding circumstances which then existed, and without regard to subsequent events."³In other words, the prior art reference must be read and interpreted though the eyes of the person skilled in the art (PSA) and using the common general knowledge (CGK) in the art at the date of publication. The relevant question to be considered is how the prior document would strike an instructed reader, and not what was in the mind of the author.⁴

What happens, however, if the prior art document does not explicitly disclose every essential feature of a claim?

It is impermissible to simply add or "fuse"⁵ CGK to a prior art document to establish lack of novelty. However, if the prior art document discloses some but not all the features of a claim, the claim is not novel if the PSA "would add the missing information as a matter of course and without the application of inventive ingenuity or undue experimentation."⁶ In other words, a claim is not novel if the prior publication does not specify an integer "but the skilled reader would understand that integer to be present in the subject matter described."⁷

A simple example of this might be if one of the steps in the claims is to react a mixture of components A and B "in a reaction vessel", and the prior art document describes the same reaction but does not specify the use of a...