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:
  1. claim construction or "Markman hearing" in which words or phrases within the claims may be rewritten by the judge
  2. 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
  3. (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).