A Proposed Solution to Jury Confusion in Patent Infringement Cases Involving Means-Plus-Function Claims

By Caliendo, Tony | Brigham Young University Law Review, January 1, 2004 | Go to article overview
Save to active project

A Proposed Solution to Jury Confusion in Patent Infringement Cases Involving Means-Plus-Function Claims


Caliendo, Tony, Brigham Young University Law Review


I. INTRODUCTION

Determining whether a patent is infringed is a question of fact1 for a jury and frequently a difficult one. juries are generally asked to determine, first, whether there is literal infringement, and second, whether there is infringement under the doctrine of equivalents. A finding of either type of infringement is sufficient to render the accused party liable. juries frequently become confused in patent cases involving "means-plus-function" claims. The confusion stems from the fact that under 35 U.S.C. § 112, determining literal infringement of a means-plus-function claim requires the jury to determine whether the accused product is equivalent to the subject matter disclosed in the patent. The subsequent determination of infringement under the doctrine of equivalents also requires the jury to determine whether the accused product is an equivalent. The question that arises, then, is whether an "equivalent" under § 112 is the same thing as an "equivalent" under the doctrine of equivalents. In other words, is there one type of equivalence or two?

According to the Federal Circuit, the expert court in patent law, the general rule is that there is only one type of equivalence. There are, however, two exceptions2 under which an accused product may be an "equivalent" for doctrine of equivalents purposes (resulting in infringement by equivalence) and yet not be a § 112 "equivalent" (resulting in no literal infringement). In cases involving one of those two exceptions, the accused product cannot be equivalent under § 112, but the jury must still determine whether the accused product is nevertheless equivalent under the doctrine of equivalents. In cases involving neither exception, a finding of equivalence requires evidence of both literal infringement under § 112 and infringement under the doctrine of equivalents, while a finding of no equivalence should result in no infringement at all. Outside of the two exceptions, therefore, a jury should never say "no" to literal infringement and "yes" to infringement under the doctrine of equivalents.

And yet, juries return verdicts finding exactly that. Recent verdicts indicate the problem is current and ongoing.3 These verdicts demonstrate juries' misunderstanding of the law. Sometimes the erroneous verdict is corrected by the district court, and sometimes the Federal Circuit has to set things right on appeal. Regardless of whether the jury alone was confused, or whether the district court was also mistaken, there exists a common failure to communicate to juries a statement of the law that is both clear and correct. This failure has the potential to seriously harm defendants in patent infringement cases involving means-plus-function claims because, as this Comment will demonstrate, where a jury's confusion regarding the notion of equivalence leads to simultaneous findings of no literal infringement but infringement under the doctrine of equivalents, that second finding may be incorrect as a matter of law, and the defendant may be wrongly held liable for infringement.

This Comment proposes jury instructions designed to clearly and correctly state the law and lead a jury to reach a correct verdict based on its determinations of fact. The instructions allow a jury the discretion to which it is entitled in determining questions of fact, while at the same time precluding the jury from returning a verdict that is incorrect as a matter of law once the jury has made its factual determinations. Following this Introduction, Part II explains several patent law fundamentals, including the legal standards for finding literal infringement and infringement under the doctrine of equivalents. Part II also explains the meanings of means-plus-function claims and the standards for infringement. Part III demonstrates how jury confusion regarding equivalence can lead to verdicts that are incorrect as a matter of law and harmful to both defendants and plaintiffs. Part III also provides two examples of recent cases in which juries reached incorrect verdicts due to confusion about the term "equivalence" in connection with literal infringement under § 112 and infringement under the doctrine of equivalents.

The rest of this article is only available to active members of Questia

Sign up now for a free, 1-day trial and receive full access to:

  • Questia's entire collection
  • Automatic bibliography creation
  • More helpful research tools like notes, citations, and highlights
  • Ad-free environment

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
Loading One moment ...
Project items
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

Cited article

A Proposed Solution to Jury Confusion in Patent Infringement Cases Involving Means-Plus-Function Claims
Settings

Settings

Typeface
Text size Smaller Larger
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

While we understand printed pages are helpful to our users, this limitation is necessary to help protect our publishers' copyrighted material and prevent its unlawful distribution. We are sorry for any inconvenience.
Full screen

matching results for page

Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.

Are you sure you want to delete this highlight?