PAT E N T S

Early this spring, in Hoffmann-La Roche,Inc. v. Promega, the United States Court

of Appeals for the Federal Circuit revieweda district court opinion on the validity of anissued patent1. The court found that draft-ing an example in the past tense, when theexperimental work had not been performedas written, could be construed as ineq-uitable conduct. Under some circum-stances, inequitable conduct can render apatent unenforceable and even result in amonetary award against the patent owner.The court remanded the case to the districtcourt to determine if the incidents ofinequitable conduct sustained by theFederal Circuit on appeal justified findingthe patent at issue unenforceable.

This article addresses one aspect of thedecision: the importance of accuratelydrafting the examples in a patent applica-tion. The required contents of a patentapplication2 include the specification, title,abstract, summary, drawings (if appropri-ate to the invention) and claims. A patentapplication need not have an examples sec-tion. However, most patents in the life sci-ences, biotechnology and pharmaceuticalareas include one or more examples. Oftenthe examples are written in a manner simi-lar to the ‘materials and methods’ section ofa scientific publication. Recently issued USpatents including examples sections are6,054,121; 6,251,594; and 6,414,130.

Examples in a patent applicationThe examples serve at least two purposes.

First, they can provide the details of howexperiments were performed, supportingdata the applicant may rely on for utility(usefulness) and enablement (operability)of the claimed invention. Second, they canprovide an outline of experiments that maybe performed in the future.

The past tense is used for examples disclosing experiments that have been per-formed as described. In contrast, ‘pro-phetic’ or ‘paper’ examples are written inthe present or future tense. If these pro-

phetic experiments subsequently are per-formed as described in the patent applica-tion, the inventors can file the experimentaldata during prosecution of the patentapplication. Often this data is submitted inthe form of a declaration under 37 CFR §1.131 or 1.132, and the patent examiner willconsider it in allowing the claims. Examplesusually will not, and in fact should not,combine tenses, unless it is to illustratevariations in how an experiment could beperformed.

Jane E.R. Potter and Gargi Talukder (summer2003) are at Davis Wright Tremaine LLP,2600 Century Square, 1501 Fourth Avenue,Seattle, Washington 98101-1688, USA.e-mail: janepotter@dwt.com

Past versus present: the importance of tense in patent application examplesJane E R Potter & Gargi Talukder

The Federal Circuit questions an example’s validity in Hoffmann-La Roche, Inc. v. Promega.

NATURE BIOTECHNOLOGY VOLUME 21 NUMBER 11 NOVEMBER 2003 1397

Box 1 Dos and don’ts

Scientists• Do use particular care when assembling protocols for use as examples. Make sure you

tell the person preparing the application which protocols were actually performed.Distinguish these from the protocols for future experiments.

• Don’t use the past tense when combining protocols. Combinations of protocols oftendo represent the best way of performing an experiment, but if the steps of theresulting experiment have not been performed as written by the time the patentapplication is filed, the example cannot be written in the past tense. It must bewritten in the present tense to signal to the examiner that it is a prophetic example.

Attorneys and agents• Do use the present tense for prophetic examples and the past tense for examples that

were performed in the way they were written.• Don’t mix tenses within a single example. If an example is a prophetic example, use

the present tense throughout. If the example was performed, stay with the past tense.Mixing tenses can lead to confusion about whether the experiments were performedas written, and this can be construed against the applicant.

Attorneys, agents and scientists• Do discuss future plans for further experimentation, and in the patent application,

include one or more examples that track methods the way the scientist plans toperform them. Once the patent application is filed, inventors should let the attorneyknow when the experiments have been conducted. Experimental data may be helpfulduring prosecution of the patent application and can be presented to the examinerafter the application is filed. For example, the data may help overcome prior art citedagainst the application, or may support utility or enablement of the invention asclaimed.

©20

03 N

atu

re P

ub

lish

ing

Gro

up

h

ttp

://w

ww

.nat

ure

.co

m/n

atu

reb

iote

chn

olo

gy

PAT E N T S

The Manual of Patent ExaminingProcedureFor interpreting the language in the exam-ples, patent examiners refer to the Manualof Patent Examining Procedure (MPEP). In asection entitled “Simulated or predicted testresults or prophetic examples,” the MPEPclearly distinguishes between prophetic andworking examples: “Simulated or predictedtest results and prophetical examples(paper examples) are permitted in patentapplications. Working examples correspondto work actually performed and maydescribe tests which have actually been con-ducted and results that were achieved.Paper examples should not be representedas work actually done.” Moreover, “Paperexamples should not be described in thepast tense”3.

Past versus present tenseHoffmann-La Roche, Inc. v. Promega empha-sizes that any example written in the pasttense is a signal that the experiment wasactually performed in the way the exampledescribes. More specifically, this means thatany example written in the past tense must

have been performed in the order in whichthe steps are written.

After Hoffmann La Roche, Inc. v. Promega,hypothetical examples are still acceptable,but, as indicated in the MPEP, and by thecourt, they must be written “prophetically,”

meaning in the present tense. The presenttense is a signal to the examiner that theprotocol may not have been performed, butthat it nonetheless portrays a sequence ofsteps and materials for conducting the

experiment. Any example written in thepast tense must have data supporting theimplicit assertion that all steps of the exam-ple were performed in the order and waythat they were written. If substantial evi-dence does not exist to support the fact thatthe example was performed as written, thismisrepresentation can potentially renderthe patent unenforceable.

Dos and don’tsHoffmann-La Roche, Inc. v. Promega pro-vides some guidelines for scientists to usewhen providing information to a patentattorney or agent, and for attorneys andpatent agents to keep in mind when draft-ing the examples section of a patent appli-cation (see Box 1). Most importantly, thereshould be good communication betweenthe groups to eliminate confusion aboutwhether an example was performed or isplanned for the future.

1. Hoffmann-La Roche, Inc. v. Promega, 323 F.3d1354 (CAFC, 2003).

2. Described in 37 CFR § 1.71.3. Manual of Patent Examining Procedure §

608.01(p)(II), August 2001.

1398 VOLUME 21 NUMBER 11 NOVEMBER 2003 NATURE BIOTECHNOLOGY

After Hoffmann La Roche, Inc. v. Promega, hypotheticalexamples are still acceptable,but, as indicated in the MPEP, and by the court, they must be written“prophetically,” meaning in the present tense.

©20

03 N

atu

re P

ub

lish

ing

Gro

up

h

ttp

://w

ww

.nat

ure

.co

m/n

atu

reb

iote

chn

olo

gy