Claim Construction Is Like Building A House – The Foundation Starts With The Specification

By Thomas A. Miller - March 25, 2015

As patent prosecutors, we do not try cases to juries. We do not argue motions before the courts. Instead, we generate the tools needed to assert the patent rights of our clients in those venues.

As such, while writing a steady stream of patent applications, it is also imperative that we stay abreast of the latest case law affecting patent practice. One Federal Circuit case from last fall caught our eye as being particularly relevant. CardSoft, LLC v. Verifone, Inc., No. 2014- 1135 (Fed. Cir. Oct. 17, 2014) is particularly relevant not for breaking new ground, but for affirming long-held standards. It also serves as good reminder of how best practices in patent prosecution can lead to powerful patents in litigation.

The patents in question were directed to software for small, specialized computers, like payment terminals or credit card readers. CardSoft asserted its US Patent Nos. 6,934,945 and 7,302,683 in this regard against Verifone. As is customary, the district court held a Markman hearing to determine the meaning of the patent claims in the asserted patents.1 A trial was then held where the jury found that Verifone had infringed certain claims of the asserted patents. Verifone appealed to the Federal Circuit.

The Federal Circuit reversed the district court based on a faulty, or in their words “incomplete” claim construction. At issue was the meaning of the claim term “virtual machine.” To ascertain the proper meaning or construction of that term, the Federal Circuit cited the seminal Phillips v. AWH Corporation decision and turned first to the intrinsic evidence at hand, starting with the specification.2 It found that the specification went through a detailed treatment of “virtual machine”, tracing its origins back to the original Java® product introduced by Sun Microsystems. Prior to Java®, so said the CardSoft specification, software had to be written in a manner compatible to the underlying hardware and operating system of the computer on which it was to be executed. As this was cumbersome and cost-ineffective, Java® introduced a “virtual machine” that acted as an interpreter between a computer application and the computer’s underlying operating system and hardware, allowing developers to write one piece of software and run it on multiple different computers and platforms. Turning to the prosecution history of CardSoft, the court noted that the Java® virtual machine was understood to be a “conventional” virtual machine. Accordingly, the court concluded, the term “virtual machine” in the context of the CardSoft patents must be construed to mean something consistent with that understanding.

The district court had construed “virtual machine” to mean “a computer programmed to emulate a hypothetical computer for applications relating to the transport of data.” The Federal Circuit disagreed based on the above analysis and concluded such a construction would be inconsistent with the intrinsic evidence in the form of the specification and prosecution, as well as the extrinsic evidence in the form of the understood meaning of “virtual machine” dating back to the original Java® product. Based on this, the Federal Circuit concluded was that “virtual machine” had to also include the limitation that “the applications it runs are not dependent on any specific underlying operation system or hardware.” Under this new construction, the court determined that Verifone’s products did not perform in this manner and found no infringement, reversing the district court.

The particular facts and claim construction of the CardSoft case are of course only germane to the parties in suit, but there are a number of practical takeaways, both for the patent prosecutor and the patent owner:

1) There is no substitute for a well-written specification. Ensuring claim terms are both defined in the specification and written in a manner consistent with that definition are key to ensuring the patent can be asserted in a desired and predictable manner.

2) The bases for construing the claims are still those set forth in the Phillips v. AWH Corporation case, namely:

  1. start by giving claim terms their ordinary and customary meaning as understood by one of ordinary skill in the art;
  2. as the person of ordinary skill in the art is deemed to read the claim term in the context of the entire patent including the specification and prosecution history, this intrinsic evidence must be considered in any claim construction; and
  3. it can also be appropriate to use extrinsic evidence to determine a term’s

meaning, but while extrinsic evidence can shed useful light on the relevant art, it is less significant that the intrinsic record in determining the legally operative meaning of claim language.

3) When writing patent applications, requesting them of your patent counsel, or reviewing drafts in-house, be vigilant in requiring your claims to not only cover your product, but at the same time to avoid indefiniteness and ambiguity. This can be facilitated through a combination of detailed personal review(s), as well as through the use of specialized patent application drafting software to which our firm subscribes.

The foregoing principles already were, and will continue to be, bedrock best practices at Miller, Matthias & Hull LLP. We start each of our applications by writing the claims to cover our product while distinguishing over the prior art, and then draft a specification that fully supports those claims and clearly defines their terms for the express purpose of ensuring a favorable claim construction for our clients. The last thing we want is for opposing counsel to convince a court that the claims, when read in light of the specification, are ambiguous, opening the door for them to bring in extraneous extrinsic evidence favoring their construction. To do so would be akin to building a house only to have it picked up and set upon something else’s foundation.

The professionals at Miller, Matthias & Hull LLP continuously strive to protect the intellectual property of our clients to the fullest extent possible while being cost-effective and budget conscious. For more information on how we can help with your IP needs, please contact us at (312)977-9902.

1 As our clients range in size from large corporations to individual inventors, we wish to point out that Markman hearings are proceedings held in patent infringement litigation, where the court determines or “construes” claim language to certain definitions for use by a jury. If the case proceeds through trial, the jury then must determine if the accused device infringes the patent claims based on the court definition or “claimconstruction.” See, Markman v. Westview Instruments, Inc., 517 US 370 (1996).
2 “Claim terms are generally given their ordinary and customary meaning as understood by a person of ordinary skill in the art…The person of ordinary skill in the art is “deemed to read the claim term not only in the context of the particular claim in which the disputed term appears, but in the context of the entire patent,” including the specification and the prosecution history.” Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005)(en banc).