Patent laws in many countries impose an onus on patent
applicants to act in good faith in dealing with the patent office.
For example, in Australia, a patent may be held to be invalid if it
is shown that the patent was obtained by fraud, false suggestion,
or misrepresentation. In the United States, applicants, inventors
and their attorneys have a duty of candour, good faith, and honesty
in dealings with the patent office and a patent may be held to be
unenforceable if there was inequitable conduct on the part of any
of those people in their dealings with the patent office.
In Australia, the full Federal Court revoked a patent directed
to a specific form of Warner-Lambert's blockbuster cholesterol
lowering drug, Lipitor (Ranbaxy Australia Pty Ltd v
Warner-Lambert Co LLC (2008) 77 IPR 449). The court held that
data included in the patent specification represented that
Warner-Lambert had found that activity of the R form of the drug
was about ten times that of the racemate (ie mixture of R and S
forms of the drug). Warner-Lambert's attorneys made a similar
representation in response to an Examiner's report on the
application. However, it turns out that all of the data available
to Warner-Lambert showed that the R form of the drug had an
activity level that was only about two times greater than the
racemate. The court found that the representation that the R form
of the drug was ten times greater was material to the patent
office's considerations in granting the patent and were false
and misleading. The patent was therefore revoked.
The charge of inequitable conduct by patent applicants,
inventors or their attorneys is also being increasingly used in the
United States to render patents unenforceable. A recent decision of
the Delaware District Court (Cancer Research Technology et al.
v Barr Laboratories et al., D-Del, Civ. No. 07-457-SLR,
January 26, 2010) provides an insight in to the extent of the duty
of good faith that is owed to the United States Patent and
Trademark Office (USPTO) by patent applicants.
Cancer Research Technology (CRT) was the
assignee of a US patent covering the tetrazine compound
temozolomide, which is marketed under the name Temodar® for the
treatment of brain cancers. A patent application was filed in 1982
and the USPTO initially rejected the application for lack of
utility on the grounds that the application did not include data
showing the efficacy of the claimed compounds in humans. CRT did
not file a substantive response but filed a series of continuation
applications over the course of ten years to effectively keep the
application alive. The USPTO rejected each continuation application
on the same grounds until, finally, in 1993, CRT filed a response
in which they argued (based on case law from 1986 and earlier case
law cited therein) that they did not need to provide data showing
efficacy in humans, and the animal test data already present in the
application was sufficient. The application was allowed based on
However, in the period during which the application was being
kept alive at the USPTO, one of the inventors published numerous
papers on tetrazine derivatives, including papers showing that some
of the compounds covered by the claims were inactive. This
information was not provided to the USPTO and the applicants
continued to pursue broad claims that covered compounds that were
known to be inactive. The court held that CRT's patent was
unenforceable. In this case, the data showing inactivity was
material to patentability and should have been disclosed to the
USPTO. This is particularly relevant as the Examiner had rejected
CRT's patent claims for lacking utility over their full scope
and the material published in the papers appeared to support the
These cases emphasise the importance of inventors and applicants
to provide all relevant data to their patent attorneys for the
purpose of preparing a patent specification and also whilst their
patent applications are pending. Consideration should be given to
disclosing to the relevant patent offices any new data, prior art
or other matter that is material to the patentability of the
invention or in conflict with earlier statements or data made in
The content of this article is intended to provide a general
guide to the subject matter. Specialist advice should be sought
about your specific circumstances.
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