How to Write a Claim Construction Tutorial
in a software patent case, by Philip Greenspun and John Morgan
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Patent litigation in the United States is expensive because a case is
tried three times:
- claim construction or "Markman hearing" in which words or phrases
within the claims may be rewritten by the judge
- a summary judgment hearing at which one side argues that the issue
of infringement or validity is so straightforward that it can be
decided without a jury hearing evidence
- (assuming summary judgment is not granted) a trial in which expert
and fact witnesses testify in front of a jury
At all three of these proceedings the judge needs to understand what
the patent describes and what the claims cover. The Federal Aviation
Administration's Aviation Instructor's Handbook
(available online)
describes one of E.L. Thorndike's "laws of learning" as "primacy":
"Primacy, the state of being first, often creates a strong, almost
unshakable impression and underlies the reason an instructor must
teach correctly the first time and the student must learn correctly
the first time. ... Relearning is more difficult than initial
learning. ... The first experience should be positive, functional, and
lay the foundation for all that is to follow."
The claim construction hearing very likely will be the first time that
the judge in a patent case has any reason to look at the patent. This
is thus an opportunity to frame the way that the judge thinks about
the patent going forward.
What is at stake
A two-step process is used when determining patent
infringement. Before the court decides if a particular patent is
infringed the scope of the patent's claims must be determined. This is
done by interpreting the terms used in the claims in order to clarify
what the patent's inventors had conceived of in order to determine the
scope of their invention. As such, claim construction is a critical
part of patent litigation. For example a patent claim may use the term
"mobile telephone" as a part of the claims. A person reading those
claims today might naturally assume that modern smartphones fall under
this definition. However, if the term "mobile telephone" is construed
as "portable wireless telephone with physical keyboard", most devices
on the market today could not infringe and the patent would be
rendered effectively worthless.
How it works
Depending on the jurisdiction, judges may want a 30-minute
presentation from an expert on each side. Alternatively, a judge may
want a document or PowerPoint slide deck that he or she can review
prior to a hearing at which attorneys will argue. Some judges employ
an independent expert, whose fees are split by the parties, to help
them read and understand tutorial documents.
An Example Tutorial
The example presented here is the defendant's
claim construction tutorial from a (settled) case where the operator
of a cloud computing services business was sued for patent
infringement. An objective of the defendant's tutorial was to show
that the patent being asserted described an invention that eliminated
the need for programmers. If this idea could be established in the
judge's mind it would be easier to win summary judgment of
non-infringment because the accused systems were complex services that
could not be used by anyone other than programmers. An additional
objective was to plant the idea in the judge's mind that the
specification was not enabling, i.e., that the claims covered a system
that was artificially intelligent and could interpret the meaning of a
stream of numbers. Figure 6 in the tutorial shows that '226 patent
claims a computer program that is able to do something that even a
human would have a tough time doing.
The style of this article is a textbook chapter. The assumption is
that the reader is intelligent and well-educated, but not a specialist
in computer programming or computer science. The idea behind writing a
textbook chapter that stands on its own, rather than a PowerPoint that
makes sense only accompanied by an oral presentation, is that the
judge can go back and review the tutorial at any time during the case.
The illustrations in the tutorial are by Mina Reimer, a long-time
collaborator of one of the authors (Greenspun), e.g., she developed
the napkin drawings in the "User
Tracking" and "Interfacing a
Relational Database to the Web" chapters of
Philip and Alex's Guide to Web Publishing (1998).
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philg@mit.edu