When Inventors and Attorneys put pen to paper and transfer an inventor's idea to writing, they are naturally limited by the words of their own language. Patent claims, which define the very boundaries of the invention, are typically limited to very few words. Thus, the choice of those words is critical. Claims should be written so that people of ordinary skill in the art can understand them and have notice as to the scope and boundaries of the invention. But lawyers writing the claims are often not of such ordinary skill and may chose their words poorly. Indeed, claims are typically written using a combination of technical and ordinary words and are mixed with legal jargon, all of which may be subject to interpretation. Not surprisingly, the dilemma of claim interpretation forms the core of many patent disputes and has led to a particularly important court proceeding in the U.S. known as the "Markman hearing."
The phrase "Markman hearing" evolved from a decision by the Supreme Court of the United States in 1996, which settled the long dispute as to who should determine what claims mean, judges or juries.1 The Seventh Amendment to the U.S. Constitution preserves the right to a trial by jury. This guarantees a patentee that a jury will decide the ultimate question of infringement. But, patents did not even include claims when the Seventh Amendment was adopted in the late eighteen century, so the debate as to whether the Seventh Amendment required juries to decide the underlying question of claim construction did not really arise until the patent statutes were amended to require claims in 1870.
In the U.S., judges generally decide legal issues and juries generally decide the ultimate factual dispute. Because the lines between the two are often blurred, for more than one hundred years courts differed as to how to label and perform the concept of claim construction. Ultimately, in its Markman decision, the Supreme Court did not categorize claim construction as a question of fact or law, but it ruled, nonetheless, that courts are better suited than juries for determining the subsidiary question of claim construction and set the job squarely on the shoulders of the judges. In resolving this critical issue, however, the Court gave no instructions to the judges on procedures for doing so.
For the first couple of years after the Markman decision, different district courts developed different procedures for handling claim construction. Some courts would construe the claims very early in the case after little discovery on the theory that the claim construction issue is totally divorced from the ultimate issue of infringement, and therefore, discovery on infringement was not necessary before claim construction. Other courts would wait until after all the evidence at trial and only then would construe the claims and instruct the jury to decide infringement based on that construction. Both procedures have obvious pros and cons. If the claims are construed too early in a litigation, the construction may be of no import because it fails to address the accused products and provide context for the overriding dispute. Indeed, the U.S. Court of Appeals for the Federal Circuit, which decides appeals from all U.S. district court patent decisions, has ruled that although the court should not prejudge the infringement issue by construing claims to include or exclude an accused product or process, knowledge of the product or process provides meaningful context for the claim construction.2
The more patent-experienced jurisdictions have recognized the importance of construing the claims after meaningful discovery, but meaningfully before trial. This process is typically favored among litigants because it resolves the critical issue of claim construction within the context of the accused products, but well before the considerable costs of a trial are incurred. Hence this process often leads to an earlier and more meaningful settlement. Unfortunately, one jurisdiction important to Chinese manufacturers, the International Trade Commission ("ITC"), does not follow this process. Instead, the ITC judges typically construe the claims after the trial at the same time they issue their determination on the merits. This process is particularly burdensome to respondents at the ITC.
Because claim construction is so vitally important to resolving disputes in patent cases, Markman hearings cannot be taken lightly. Indeed, though a Markman hearing may occur well before the trial, the parties should have fully developed their positions on the merits by this time to ensure that their claim construction positions are consistent with the evidence in the case. Both parties in a patent litigation must typically navigate tens of thousands of documents related to accused products and numerous pieces of prior art. At a Markman hearing, good litigators will be fully steeped in this evidence and the issues of their cases and prepared to address any issues the judge may have.
Often judges will request a brief tutorial on the technology of the patent either before or in conjunction with the Markman hearing. This is a great opportunity to stage your case in your favor. Lawyers often hire graphics consultants to help create insightful and persuasive graphical animations and tutorials for the judge. This is costly, but it is money well spent as most U.S. judges do not have technical backgrounds.
To properly construe patent claims, judges are required to focus primarily on the words of the claim and the patent specification. Indeed, the specification is considered the single best guide to the meaning of a disputed claim term.3 Thus, a good Markman presentation is grounded in the disclosure of the patent specification. Typically, defendants accused of infringing overdo it a bit and try to limit the claim scope to just the embodiments expressly disclosed in the patent specification, while patentees counter with the axiom that claims should not be limited to only the disclosed embodiments. Judges often decide on something in between.
The courts will also look at the prosecution history--the record of correspondence between the patent applicant and the U.S. Patent and Trademark Office ("PTO")--to help construe the claims. The PTO typically rejects a patent application one or more times based on prior art and other requirements, and the patent applicant responds accordingly. This record of correspondence helps the judge decide what the invention is intended to cover and not to cover. Therefore, at a Markman hearing, good lawyers have a full understanding of the prior art cited by the PTO and the arguments made by the PTO and the patentee and can articulate where the prior art ends and the invention begins.
The courts are also permitted to consider other evidence, known as "extrinsic" evidence, but extrinsic evidence is generally considered less reliable than the "intrinsic" patent specification and prosecution history.4 According to the Federal Circuit, undue reliance on extrinsic evidence poses a risk that it will be used to change the meaning of claims in derogation of the indisputable public records consisting of the claims, the specification, and the prosecution history.5 While the Federal Circuit has advised courts to use discretion when considering extrinsic evidence, some forms of extrinsic evidence are considered less controversial and more helpful. Thus, good lawyers should consider these more credible forms of extrinsic evidence and present them at a Markman hearing to their advantage.
One credible source of extrinsic evidence is the dictionary, which is often consulted, particularly for non-technical terms in a claim. Technical dictionaries, such as the IEEE Dictionary, are more typically consulted for more technical terms, but credible treatises and encyclopedias can also be considered.
If an Inventor is a compelling witness, patentees may try to have the Inventor testify at the Markman hearing. Some courts permit this, others do not. The U.S. Court of Appeals for the Federal Circuit has informed that an inventor's testimony as to the proper claim construction is typically not helpful because it can be biased and self-serving.6 Defendants may also try to introduce an inventor's testimony where a defendant feels the inventor has admitted a certain meaning about the claims that demonstrates no infringement. But even for such alleged admissions against interest, the Federal Circuit has cautioned against relying on the inventor's subjective intent.7
Given the controversy about an inventor's testimony, the parties more typically depend on testimony from an expert at Markman hearings, either through live testimony or written declarations submitted with briefs. Again, given the significance of a Markman ruling in resolving a patent dispute, good lawyers have their experts involved in the case early so that they fully understand the positions and are well prepared to provide relevant testimony at a Markman hearing. This too can be costly, but again, it is money well spent.
The dockets for U.S. judges are very crowded, so they do not have much time for any one case. Therefore, every opportunity before a judge is critically important and the arguments to be made should be well thought out. Good lawyers ask a judge to determine only the critically important claim construction issues. In the weeks leading up to a Markman hearing, the parties typically engage in negotiations to try to narrow the list of disputed terms. Parties that refuse to respect this process and require the judge to construe numerous terms may lose credibility with the judge. Thus, good lawyers focus on the critical limitations that can effect the infringement or validity analysis of a claim and avoid unnecessary claim construction issues.
Judges typically do their best to issue their rulings on claim construction within a reasonable amount of time after the Markman hearing, but given the demands of their dockets, this is not always possible. In these instances, the case is greatly complicated as it moves forward because the parties and their experts must develop alternative positions taking into account both sides' proposed claim constructions. Nonetheless, once a court issues its claim construction order, regardless of the timing, the parties have far more clarity on the issue and the overriding dispute. Obviously, this new insight helps to promote settlements.
In short, the Markman hearing in U.S. patent litigation has become a critical procedure, second only to the trial itself. Limitations of language leave claims subject to the interpretation of the reader, which leads to the core of many patent disputes. Courts have been instructed that they must resolve these disputes about interpretation and construe the claims for the litigants. To do this, judges must parse through the extensive and often confusing intrinsic and extrinsic evidence and make sense of it. Given that most judges do not have technical backgrounds and their dockets are typically crowded, claim construction can be a particularly demanding task for a judge. The Markman hearing represents a party's key opportunity to assist the judge with his or her task and to guide the judge through the evidence in a credible and convincing manner. This opportunity must be taken seriously by the lawyers and be fully supported by the client. Good advocacy here can lead to a positive claim construction ruling and enhance the possibility of settlement, saving the client the tremendous expense of a trial.
