|| The Concept of Infringement. A patent contains
one or more claims, which constitute the scope of the invention. If
someone has an application that uses each and every element of any claim
in a patent, then that application literally and directly infringes on the
How Can a Patent Be Infringed? A patent can be
infringed either directly or contributorily.
1) Direct patent infringement is covered under 35 USC 271(a) and applies when:
- The claim language is legally defined and interpreted by a
- Then, a jury (or a judge when a jury is not requested) determines
whether the legally- defined and interpreted claims cover the accused
device or process.
Note that there is no intent or knowledge element required to prove direct infringement. Direct infringement is analogous to a strict-liability offense because it requires no more than the unauthorized use of a patented invention: knowledge or intent is legally irrelevant. However, direct infringement is only available against those who practice each and every element of the claimed invention.
2) Contributory patent infringement is covered under 35 USC 271(c) and applies when someone
encourages someone else to directly infringe a patent plus two other
conditions are present:
- that the allegedly infringing device is not a staple article or
commodity of commerce suitable for a substantial non-infringing use;
- that the alleged contributory infringer knew of the asserted patent
and that its activities would cause infringement of that patent.
3) Induced infringement is covered under 35 USC 271(b) and covers process (method) claims. Induced patent infringement can be found when:
- a party performs some of the steps of a patented method and induces another party to perform the remaining steps; or
- when a party induces multiple third parties to collectively perform the steps of a patented method, but no single party has performed all of the steps.
To be liable for induced infringement, the accused infringer must have knowingly induced the infringement. The accused infringer must have knowledge that the steps being encouraged are covered by the patent. But one can defeat a charge of induced infringement if the alleged infringer has "a good-faith belief of invalidity [of the patent because such belief] may negate the requisite intent for induced infringement." Commil USA v. Cisco Systems Inc., Fed. Cir., No. 2012-1042, 25-JUN-2013.
Statutory Law. Section
271(a) of title 35 of the United States Code defines direct infringement:
"whoever without authority makes, uses, offers to sell, or sells
any patented invention, within the United States or imports into the
United States any patented invention during the term of the patent
therefor, infringes the patent."
Equivalents. In addition, the doctrine of
equivalents expands the scope of a patent beyond its literal terms to
equivalents of what was claimed. The notion of the doctrine of equivalents
in patent law is that unimportant substitutes for certain elements will
not evade the protection offered by a patent because otherwise such
substitutions would unfairly destroy the value of a patent.
The Federal Circuit explains in its now famous 2002 Festo
decision, "The doctrine of equivalents allows the patentee to
claim those insubstantial alterations that were not captured in drafting
the original patent claim but which could be created through trivial
The Federal Judicial Center publishes a 17-minute
video (QuickTime, Real Media and Windows Media Player formats)
"designed to be shown to jurors in patent jury trials. It contains
important background information intended to help jurors understand what
patents are, why they are needed, how inventors get them, the role of the
Patent and Trademark Office, and why disputes over patents arise." It
is about 65 megabytes in file size.
Applying the Doctrine of Equivalents. In
applying the doctrine, the invention as a whole is not the focus of an
equivalents determination. Rather, this doctrine is applied by examining
each element contained in a patent claim to determine equivalency of an
element or part of the invention with the one that is substituted in the
accused product or process. This is important because a focus on the
elements of a claim ensures that the application of the doctrine does not
result in the vitiation or elimination of any such element. The important
thing to remember is that the doctrine of equivalents extends protection
beyond the literal terms in a patent and no matter how careful one is,
such expansion can create uncertainty about what the patent protects.
Court Decisions Narrow Doctrine of Equivalents.
The doctrine of equivalents has been scaled back in recent times. Legal
principles of "prosecution history estoppel" and "file
wrapper estoppel" can eliminate the doctrine when amendments to a
patent application were made to avoid prior art, or otherwise
to address a specific concern--such as obviousness--that arguably would
have rendered the claimed subject matter unpatentable. The legal concept
is that if the applicant responds to patent office action on his
application by narrowing the claims, then this prosecution history
precludes the applicant from later reclaiming the subject matter by
arguing it is an equivalent.
Nonetheless, one must be careful when attempting to design around a patent
so as to avoid both literal patent infringement and infringement under the
doctrine of equivalents. The Supreme Court said in its 2002 Festo
decision, "Though prosecution history estoppel can bar challenges
to a wide range of equivalents, its reach requires an examination of the
subject matter surrendered by the narrowing amendment." Festo
Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., Ltd., 535 U.S. 722,
737, 122 S.Ct. 1831, 1840, 62 USPQ2d 1705 (2002),
Designing Around, A Good Thing? Designing
around a patent is considered an important public benefit of the patent
system. A competitor's designing around a patent's claims "is
the stuff of which competition is made and is supposed to benefit the
consumer." State Indus., Inc. v. A.O. Smith Corp., 751
F.2d 1226, 1236, 224 USPQ 418, 424 (Fed. Cir. 1985). In a trial for
infringement, the "fact-finder may infer that the competitor,
presumably one of skill in the art, has designed substantial changes into
the new product to avoid infringement. . . .Evidence of designing around
therefore weighs against finding infringement under the doctrine of
equivalents." Hilton Davis Chemical Co v. Warner-Jenkinson
Company, Inc., 93-1088 (Fed. Cir. 1995).
Designing around an existing patent may
require a review of more than the literal terms of a patent.
An infringement determination should be
made only after considering the law that is applicable.
If you think someone has infringed your
patent, Attorney Louis Ventre, Jr. would be pleased to discuss legal
representation with you on an hourly or fixed-price, fixed-tasking
retainer basis. Please contact
Attorney Louis Ventre, Jr. to discuss this in a free initial
If you are worried about whether your
existing design around was adequate, it is not too late to get a
If you have received a letter demanding
you cease and desist infringement, read on.
Other related pages that may be of interest
are patent infringement
opinions | infringement
damages | and pharmaceutical importation and
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This file last modified 08/28/13.
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