Claims?? We Don't Need No Stinkin' Claims!!! (Or Do We?)
November 2001
In this article, Sanford Warren Jr. explains
the parts of a patent: the written description and the undecipherable claims
section, as well as the scope of rights granted under a particular patent.
by Sanford
E. Warren Jr. and Kenneth T. Emanuelson
Winstead Sechrest
& Minick
As noted in previous articles, the U.S. patent system incorporates a huge
body of relatively quirky rules and concepts, many of which are counterintuitive—or
at least non-intuitive. In the previous article in this column, What Does the Word "Comprising" Mean, and Why Should
I Care?, we discussed two of the more esoteric aspects of patent law. The
first was the purely "negative" nature of patent rights, under which a patent
holder has a "veto" over the actions of other parties. The second was the "collective"
nature of patent ownership, under which each part-owner of a patent has complete
and transferable rights to the patent. This article focuses on the scope of
the rights granted under a particular patent.
The Written Description of the Invention versus the Claims Section of the
Patent
Although a few clients pursue patents primarily because they are proud of
their ideas and want to publish them to the world, most pursue patents because
they hope to gain a competitive market advantage over their closest competitors
in the market. For the first group, the scope of the rights granted under the
issued patent is not of great concern. For the second, those seeking to use
patents as competitive tools, the scope of the rights granted under the issued
patent is the crucial point of the whole exercise.
Anyone who has read an issued U.S. Patent knows that they are generally not
the most exciting documents to read. In fact, owing to the process under which
they are generated and the goals for which they are drafted, patents can be
some of the driest reading this side of the Internal Revenue Code. At the same
time, in a well-drafted patent, every word is there for a reason, although not
all words carry the same weight. As discussed below, certain words and passages
in a patent are significantly more important than others.
In general, a person inexperienced in patent law will tend to treat the patent
write-up as a technical paper, not as a legal document. In fact, a patent is
both. One of the principal purposes of patent law is to create a publicly accessible
database of scientific and engineering knowledge. Most patent applicants do
not, of course, file patent applications out of altruism. Most file to acquire
a legal monopoly over a certain technology claimed in the patent.
For a private entity to acquire a patent monopoly, the patent law requires
that the inventor disclose to the public what he or she knows about the technology.
The patent process, in other words, is founded on a bargain between the inventor
and the public. In exchange for a limited monopoly on the invention, the inventor
must reveal his "secrets" to the public in the body of the patent. In practice,
the "secrets" are generally buried in the middle of a lengthy technical write-up
guaranteed to put readers soundly to sleep before they get to any useful information,
so the inventor's secrets are usually still pretty safe.
To a technologist, the technical write-up, or "written description," of the
invention is the most useful portion of the patent. To a lawyer, the written
description is often the last part of the patent read. Being more interested
in the legal scope of the patent rather than the scientific and technical details
of the technology, the lawyer will generally skip to the very last section of
the patent, where "claims" are found.
Deciphering the Claims Section
As difficult as most patents are in general, the unwary will often reach
the claims completely unprepared for the odd legalese that lies therein. The
written description may be complicated and dry, but at least it's in English.
A sample of a written description of an issued patent reads as follows:
In accordance with one embodiment, as illustrated in FIG. 1, a parallel
concatenated turbo encoder 10, or turbo coder 10, includes first and second
coders 12, 14, an interleaver 16, and a multiplexer 18. The first coder
12 and the interleaver 16 are configured to receive encoder input data 20,
which is typically user information or control data. The first coder 12
outputs systematic symbols 22, which are typically a copy of the original
input bits 20, and parity symbols 24. The second coder 14 is configured
to receive an interleaved output 26 of the interleaver 16 and to output
a second set of parity symbols 28. The systematic symbols (not shown) generated
by the second coder 14 are suppressed, and the remaining respective outputs
22, 24, 28 of the first and second coders 12, 14 are multiplexed by the
multiplexer 18 into an output data stream 30...
Anyway, you get the idea. Hello? I see you're drifting off already? I'd suggest
you snap out of it, because, as the song says, "You ain't seen nothin' yet."
The above is only a small excerpt of a patent that goes on for many pages. So
you can see why the written description can be slow-going, unless you're really
into parallel concatenated turbo encoders. After several pages of detailed technological
jargonese similar to the above, the reader will generally be met with something
at the end of the patent that looks like this:
1. A turbo coder, comprising:
a first coder configured to receive a plurality of input bits in
succession and generate a first plurality of output symbols therefrom;
an interleaver configured to receive the plurality of input bits
in succession, the interleaver including a plurality of bit storage
locations arranged in a matrix of rows and columns and a linear congruential
sequence generator configured to pseudo-randomly generate a sequence
for shuffling bits within each row of the interleaver; and
a second coder configured to receive a plurality of interleaved bits
in succession from the interleaver and generate a second plurality of
output symbols therefrom.
As you can see, although claims mostly use English words, they're not written
in a form that could legitimately be described as English syntax. The astute
will notice that the above text is one continuous "quasi-sentence," beginning
with a capital letter and ending with a period. This is not an accident. This
form of claim is not merely allowed by the patent rules; it is mandated. This is true whether a claim spans
three lines or three pages.
The astute will also realize why the claim is referred to as a "quasi-sentence."
The above excerpt has no predicate, merely
a relatively detailed elaboration of an object.
Under patent rules, each claim is to read as if it begins with the words, "I
claim.…" When you read the above claim 1 with those words added, it makes a
little more sense. At least it becomes a real sentence. Sort of.
You may also notice the use of the word "comprising" in the first line of
the claim. Although it's not really used often outside the patent business,
"comprising" is, believe it or not, a real English word. According to the dictionary,
it has a meaning very similar to "including." In the patent business, the word
"comprising" has the very specific meaning: "including at least the following."
In light of this, you can see that the preamble to claim 1, which reads "A
turbo coder comprising:" should be read as: "I
claim a turbo coder including at least the
following:" Read in this way, it makes even more sense. That is, the
inventor of the invention described in the patent is making a legal claim to
turbo coders that include at least a "first coder," an "interleaver," and a
"second coder." In other words, a turbo coder that does not include at least these three elements would not
be covered by claim 1. From that point, questions will no doubt arise as to
whether the "first conflugalization processor" in a competitor's "super conflugalizer"
is the same as the "first coder" in the patent, but the analysis of those questions
is beyond the scope of this particular article.
With all of the odd formalities and quirky construction rules used by patent
attorneys in drafting patent claims, it's easy to understand why most non-lawyers
tend to ignore the claims when reviewing a patent. With respect to the use of
a patent for a competitive advantage, however (that being the purpose for which
most clients acquire patents in the first place), the claims are absolutely
crucial. As noted, it is the coverage of the claims, rather than the written
description, that defines the scope of the monopoly granted under the patent.
The important point is to understand the relevancy of the claims to the function
and purpose of the patent itself.
The Patent Prosecution
To understand the reason why a narrow set of claims is often accompanied
by a broad description, it is helpful to understand the patenting process. What
often occurs during the patenting process, known in the business as "patent
prosecution," is that a patent attorney will prepare an extensive written description
covering every aspect of a certain embodiment of a client's new invention. Then,
after filing, it will be discovered that most of the aspects of the new invention
have been done before, such that a patent on a device or method covering just
those aspects would be improper. A skilled patent attorney will generally be
able to identify one or more distinctions between prior devices and methods
and her client's invention, even if the devices share many features.
So long as identified distinctions are not obvious in light of the "prior
art," an inventor is entitled to patent claims directed to those distinctions. Consequently, the patent will
issue with a relatively extensive written description but a relatively narrow
set of claims. In this situation, an engineer reviewing the patent can be forgiven
for reviewing the patent as a whole and coming away with a belief that the patent
"covers" what it describes. In its capacity as a technical document, it does,
but in its capacity as a legal document, it doesn't necessarily. In fact, a
patent's claims generally cover only a small subset or particular combination
of the material described in the written description.
Conclusion
As discussed, it is very important to take a close look at the claims before
making even a small business decision based on the existence of a patent. To
steer clear of a business because it is believed to be protected by a competitor's
patent, or to invest in a market in reliance on an extensive patent portfolio,
is inadvisable prior to a good, hard look at the claims.
Ken Emanuelson is an associate with the intellectual property section of Gardere & Wynne, LLP.
His clients range in size from small startups to established Fortune 500 companies,
in various areas of technology, from online commerce to aerospace. His regular
practice includes client counseling in all areas of intellectual property law,
patent and trademark drafting and prosecution, litigation, licensing negotiation,
and infringement analysis. In his prior career as an engineer, Mr. Emanuelson
worked for Texas Instruments and Ford Motor Company. His engineering experience
included work in semiconductor processing, factory automation, microwave communications,
aerospace materials, automotive technology, and superconductive ceramics. Mr.
Emanuelson is a graduate of the University of Texas School of Law, where his
course of study focused primarily on patent, trademark, and copyright law. He
also holds a BS degree in mechanical engineering from the University of Arkansas.
He can be reached by email at .
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