An exercise in fishing: no discovery of inventor’s notes in Australian biosimilar patent spat

Summary

Historically in Australia, discovery of documents concerning the development of an alleged invention, including inventor’s notes, has been considered as habitually allowed. This is provided that they are directly relevant to an issue raised by the pleadings based on the principles in Wellcome (Wellcome Foundation Limited v V.R. Laboratories (Aust) Pty Ltd (1981) 148 CLR 262). 

However, where Samsung Bioepis’ lack of inventive step case extended to a “welter” of combinations of prior art, Burley J considered that the discovery application was an impermissible fishing exercise (Pfizer Ireland Pharmaceuticals v Samsung Bioepis AU Pty Ltd (No 4) [2024] FCA 678) that was not relevant to the pleaded case.

His Honour did allow discovery directed at the best method known to the patentee, in circumstances where a named inventor had given evidence that tended to suggest the patentee agreed it had not done so. 

Background

Following a series of preliminary discovery applications, in May 2022, Pfizer commenced proceedings in the Federal Court of Australia against Samsung Bioepis, Merck, Sharp & Dohme, Organon and Arrow (the Respondents).  

Pfizer contends that the Respondents’ manufacture and use of etanercept infringes its patent,  AU 2005280034, entitled “Production of polypeptides” (the Patent).

The Respondents have crossed claimed, saying that the Patent is invalid on various grounds including for lack of inventive step and failure to disclose the best method.

This decision concerns the Respondents’ application for non-standard discovery, namely:

1.  All documents created from 27 August 2002 until 27 August 2004 recording or evidencing research, development or experimental work on the subject invention (Category 1); and
2. All documents created before the Filing Date concerning the production of etanercept as described in example 16 of the Patent (Category 2).

The broader proceedings are listed for hearing for three weeks in September and October 2025. The parties are due to file their evidence in chief at the end of this year.

Decision

Category 1

In Australia, whether an invention is obvious is “an objective test, based on the imputed skills and knowledge of a notional person, which is a remove from the steps taken by the inventors themselves.”

The Respondents’ obviousness case was put on the basis of common general knowledge alone, but also a “welter” of combination of prior art documents – adding up to more than 80…