When an inventor files a patent application for an invention with the United States Patent and Trademark Office and is granted a patent, the patent provides the inventor with the right to exclude others from making, using, or selling the claimed invention. The claims of a patent, which are the paragraphs found at the end of the patent, set forth in words the scope of the patent owner’s right to exclude. If the patent is then litigated, the claims of the patent will be construed to determine what the claim terms mean. The Federal Circuit is currently deciding Phillips v. AWH Corporation, 363 F.3d 1207 (Fed. Cir. 2004), vacated, 376 F.3d 1382 (Fed. Cir. 2004), en banc, and it is poised to address the issues of what role dictionaries and treatises should play in the claim construction process.

Markman Suit off track

At first blush it would seem that the issue of patent claim construction was settled by the well-known Markman v. Westview Instruments, Inc., 53 F.3d 967 (Fed. Cir. 1995), aff’d, 517 U.S. 370 (1996) case. In Markman the patentee owned a patent for an inventory control system that monitored the progress of articles of clothing as they moved through a dry cleaning plant. In the system, data pertaining to the customer, the articles of clothing, and the cleaning to be carried out was entered into a data processor, and tags with bar codes were printed and attached to the articles of clothing. Optical detectors were used to track the bar codes on the tags so that inventory could be tracked during the cleaning process. The patent claimed “a data processor including . . . means to maintain an inventory total.” Competitor Westview had two devices, one called DATAMARK and another called DATASCAN. Customer data, data on articles to be cleaned, and data on charges for the cleaning was entered into the DATAMARK device, and the DATAMARK device printed a bar-coded ticket. The DATASCAN device was portable and could be used to read the bar-coded tickets attached to the clothing at any location in the dry cleaning store, but could not track articles of clothing. Markman sued Westview for patent infringement and lost.

Rely on the evidence

The Federal Circuit in Markman discussed the two-step test for assessing patent infringement. The first step of infringement analysis is to construe the allegedly infringed patent claim. The second step is to compare the properly construed claim to the accused product. If the comparison reveals that each element or limitation in the claim is found in the accused product, then the claim is said to “read on” the accused product and the accused product infringes. The first step requires a court to determine what a patent claim term actually means. A court construing a patent claim term can use intrinsic and extrinsic evidence. Intrinsic evidence includes the description in the patent, the patent claims, and the prosecution history of the patent if the history is in evidence. The intrinsic evidence is fixed at the time the patent is granted. Under Markman, extrinsic evidence includes all evidence external to the patent including dictionaries, treatises, and expert testimony. A court can use its discretion when considering extrinsic evidence to understanding the patent, and should not use extrinsic evidence to contradict or vary claim terms.

In Markman, Claim 1 called for a system that included, among other things, “a means to maintain an inventory total,” and the issue was whether Westview’s device infringed the claim. The lower court construed the term “inventory” to mean “articles of clothing,” and under the lower court’s construction the claims required the system to be able to track “articles of clothing.” Since it was undisputed that the device of Westview was incapable of tracking “articles of clothing,” the lower court granted a judgment of non-infringement. Markman appealed and the Federal Circuit, relying primarily on intrinsic evidence, also construed the claim term “inventory” to mean “articles of clothing.” The Federal Circuit affirmed the lower court’s judgment of non-infringement.

Markman is also a very important case in patent law because it also held that in patent infringement cases tried to a jury, the court has “the power and obligation to construe as a matter of law the meaning of language used in the patent claim.”

Look it up

More recently, cases have significantly expanded the use of dictionaries when performing a claim construction analysis. For example, in Texas Digital Systems, Inc. v. Telegenix, Inc., 308 F.3d 1193 (Fed. Cir. 2002), the Federal Circuit indicated that claim terms should be given their ordinary meaning, unless there is a compelling reason why they should not be given their ordinary meaning. The Federal Circuit noted that when a patent issues, dictionaries and treatises publicly available at that time are objective and reliable resources of information as to the ordinary meaning of a claim term. The Federal Circuit also noted that dictionaries do not fit in the category of extrinsic evidence, and that dictionaries may be consulted by judges at any time during litigation whether or not offered into evidence by a party. Significantly, the Federal Circuit in the Texas Digital Systems, Inc. decision warns that going to the patent and prosecution history as a first step in construing a claim could result in bringing additional limitations into the claim. This case illustrates how some courts construe a claim by first resorting to a dictionary, before considering the patent description and prosecution history of the patent.

If dictionary definitions are to be the starting point for purposes of claim construction, however, issues quickly arise as to which dictionary should be used, whether technical dictionaries should be used, and what should be done in the event there are a plurality of different dictionary definitions. The Federal Circuit will hopefully address these issues when it decides the Phillips case. In this case, Phillips owned a patent that claimed building modules consisting of vandalism-resistant modular wall panels. Phillips entered into an agreement with AWH Corporation. After the agreement ended, AWH Corporation continued marketing and selling the modules. Phillips sued for patent infringement. The modules at issue were constructed of inner and outer panels having inwardly directed baffles. The modules were fire and impact resistant, provided for acoustic insulation, and could support axial loading. Claim 1 recited, in part, “means disposed inside the shell for increasing the load-bearing capacity comprising internal steel baffles extending inwardly from the steel shell walls.” The district court construed the claim term “baffles” and concluded that the “baffles” had two properties. One property was that they extend inwardly from the shell walls at oblique or acute angles, and the other property was that they form an intermediate, interlocking barrier in the interior of the wall module. Phillips conceded it could not prove infringement under this definition, and the district court granted AWH’s motion for summary judgment of non-infringement.

Phillips appealed, and the Federal Circuit referenced Webster’s dictionary and noted that the term “baffle” is entitled to its ordinary meaning, and affirmed the district’s court judgment in favor of AWH. Phillips filed a petition for a rehearing en banc, and the Federal Circuit granted the petition and vacated the earlier decision.

The Federal Circuit then requested that bar associations, trade and industry associations, government entities, and other interested parties file briefs directed to several important questions. These questions include the following:

1. Should technical and general purpose dictionaries be used in claim construction or should the claim terms be interpreted in view of the specification, and if both sources are to be used, in what order should they be considered?

2. What use should be made of general as opposed to technical dictionaries, and what should be done in instances where there are multiple dictionary definitions of the same term?

3. If the primary source for claim construction is the specification, what use should be made of dictionary definitions of claim terms?

4. What role should the prosecution history of the patent and expert testimony play in determining the meaning of the disputed claim terms?

Thus, it appears that the decision of the Federal Circuit in this case will have a significant impact on current claim construction practice. We will keep you apprised of developments as this case progresses.

John M. Del Vecchio concentrates his practice in all aspects of intellectual property law including patent, trademark, and copyright law. In addition to the mechanical and electromechanical arts, Mr. Del Vecchio’s patent practice has expanded to include business method patents.