Markman Hearing


Markman Hearing

A Markman hearing is held to determine the meaning of disputed claims in patent litigation. During the hearing, the judge will look at the claims in the patent application and patent grant to determine the protected portions of the invention.

What is a Markman Hearing?

This type of hearing, also known as a claim construction hearing, is essential in determining issues of patent infringement because the patent claims define what is and is not protected intellectual property. Although a jury, as the trier of fact, will determine whether or not infringement occurred.  This includes cases being determined under the doctrine of equivalents.  The judge, as the trier of law, will determine how the claims should be interpreted. Thus, the judge, through claim construction, will determine the scope of the patent holder’s rights. The judge’s determination in the Markman hearing will be incorporated into the jury’s instructions.

The name of the hearing comes from Markman v. Westview Instruments, a 1996 Supreme Court case that decided that judges are in a better place to determine the meaning and definition of words in patent claims than juries are due to their experience in interpreting the written language in complicated contracts and statutes. Having this rule in place creates more uniformity across all federal districts, as judges are bound to give weight to other courts that have ruled on similar claims.

Patent Claim Construction

Patent claim construction is the first step of any infringement case. Before examining the allegedly infringing object, the court must determine the scope and meaning of the patent claims asserted.

When conducting this determination, courts will consider both intrinsic and extrinsic evidence.

Intrinsic Evidence

Intrinsic evidence refers to materials submitted as part of the patent application. This includes:

  • The patent application itself, including the claims, summary, and written description,
  • Written or oral communication between the patent applicant and the patent examiner that comprises the prosecution history,
  • Previous related patents and their prosecution history,
  • Prior art referenced in the patent application.

This evidence can point to the thought process of the patent applicant at the time of patent prosecution and is given significant weight by courts conducting claim construction.

When looking at intrinsic evidence, courts must consider how patent claims are drafted.

Claim drafting itself is a bit of an art and a science. When claims are initially drafted, applicants use a combination of plain English, otherwise known as “lay terms,” technical or scientific language, and terms of degree, such as “about” or “around.”

Complicated technical or scientific language, such as the names for compounds, can be examined by utilizing extrinsic evidence found in dictionaries, treatises, or through cross-examination of expert witnesses. These are often the easiest terms to interpret because they require little further analysis.

It is often the seemingly simpler words found in lay terms and terms of degree that require deeper legal analysis. Because patents often involve highly technical descriptions, lay terms and terms of degree may take on special meaning in a particular subject matter. This can make it difficult to determine which words or phrases should receive additional clarity and be examined under a technical or scientific lens and which should be left for interpretation by the jury.

Often, patent claims are not drafted by the creator of the invention, but by a patent attorney familiar with the science or technology utilized, with the goal of protecting as much as possible of the invention, while drafting claims narrowly enough that they do not encompass prior art and become unpatentable. Courts engaging in claim construction understand this balance.

Once the application is submitted to the Patent Office, the patent examiner may request revisions to the claims to ensure the invention is patentable – that is, the elements claimed for protection must be new, useful, and non-obvious. The prosecution of patent applications can thus result in disclaimers and amendments to the claims, based on discussions with the patent examiner. Courts will take into consideration disclaimers of what the patent does not cover, when interpreting the meaning of claims in the patent grant.

Additionally, because of this back-and-forth negotiation, although claim drafters think ahead to potential future infringement cases, a primary goal at this stage is often a speedy patent grant. As a result, while patent prosecution history can play a role in claim interpretation, courts utilize this back-and-forth for greater clarity as to lay terms and terms of degree, but the negotiation itself may be more ambiguous than either the original application or the final grant.  For more information see our prosecution history estoppel page.

Extrinsic Evidence

Extrinsic evidence is any evidence that comes from other sources. In Markman hearings, extrinsic evidence may include:

  • Dictionary definitions for standard words,
  • Encyclopedias or engineering dictionaries for technical terms,
  • Journals or other scientific treatises discussing the technology,
  • Testimony from the patent applicant, or
  • Expert testimony.

While courts primarily examine intrinsic evidence to assist in claim construction, extrinsic evidence is useful for education and background information on the invention in question.

Patent Claim Construction Rules

The current standard for patent claim construction is found in Phillips v. AWH Corp., a 2004 Federal Circuit case. This case, along with subsequent decisions relying on Phillips, have created a framework for claim construction. There is no fixed methodology for determining proper claim construction. Instead, there are a series of principles utilized when determining the proper construction.

Under Phillips, a leading principle is that each claim term must be given “the meaning that the term would have to a person of ordinary skill in the art in question at the time of the invention,” which is the effective filing date of the patent. The meaning assigned by the person of ordinary skill in the art is deemed to be the “ordinary meaning” of the claim terms, which is the “objective baseline” of claim construction. However, this ordinary meaning may not be the proper construction of the claims.

Courts must also consider both intrinsic and extrinsic evidence in determining how claims should be constructed. Intrinsic evidence is highly favored in Markman hearings. This evidence goes to the heart of how claims should be interpreted.

Part of the importance of intrinsic evidence comes from the principle that claims must be read in view of the specification, which is always highly relevant to claim construction analysis. Specifications are the best guide to the meaning of a disputed term. Specifications may contain a special meaning to a claim term or an internal disclaimer that would govern claim construction. As a result, courts should rely heavily on the specification and written description. Prosecution history will play into the review of intrinsic evidence, although it may lack clarity, due to the nature of negotiations between the patent applicant and the patent examiner.

Extrinsic evidence, on the other hand, such as dictionary definitions and expert testimony, may be utilized for background education on a particular matter. While courts generally permit introduction of this evidence, it should not be substituted for a reading of the claims and viewing the document as a whole.

Because extrinsic evidence is not written with the particular claimed patent in mind, there is a risk it could be utilized to change the meaning of the claimed terms and potentially expand the scope of the patent.  However, extrinsic evidence can be extremely useful to understand what an ordinary skill in the art would have been at the time of the effective filing date.

This question of timing is another important principle because technology often moves at a rapid pace. Utility patents are valid for 20 years, and design patents are valid for 14 or 15 years. To put this into context, the first-generation iPhone will have the benefit of patent protection until the late 2020s. Utilizing scientific and technological treatises written on relevant subjects in the early 2010s, when the design patent was originally filed, is extremely relevant to understanding the level of skill at that time.

When constructing claims, courts can rely on previous court decisions for interpretation of common lay terms, in order to preserve uniformity in decisions. Courts may also correct minor mistakes and typos in claim language, if there is no reasonable debate as to the correction. However, major errors may only be corrected by the Patent Office.

The Phillips court included a principle that claims should be construed in a way that preserves patent validity. However, this principle typically only comes into play when there are two equally viable interpretations of a claim, one which favors validity and one that does not. In this situation, courts will opt for the interpretation that preserves patent validity.

Patent Construction Rules at the U.S. Patent Office

In November 2018, the U.S. Patent Office finalized a rule in order to bring its patent claim construction rules in line with the Federal Circuit’s decision in Phillips. This rule, laid out in 37 CFR 42.100, governs how the Patent Office will construe patent claims for inter partes review (IPR), post grant review (PGR), and covered business method patents (CBM) proceedings.  It is important to note that this rule will apply only to petitions filed after its adaptation, so it may be some time before we see how it impacts filings with the Patent Office.

Under the rule, the Patent Office will take into consideration any prior claim construction determination made in a civil case or in a proceeding before the International Trade Commission (ITC), as long as that determination is properly entered into the record. Thus, under new rule, federal court and ITC decisions arising from disputes between two parties may lead to issue preclusion at the Patent Office.

This rule replaced the “broadest possible interpretation” (BRI) standard, which required parties challenging a patent claim to show that the claim was being interpreted more broadly than how a court would interpret the claim. This standard often increased the possibility that a claim would be interpreted as encompassing prior art and, in turn, lead the patent to be cancelled as it covered unpatentable subject material.

Under the BRI standard, claimed words are given their ordinary and customary meaning, unless the patent applicant defined terms in a specific manner in the specification. Extrinsic evidence may be considered, but intrinsic evidence is favored.

The broadest possible interpretation rule will remain in effect for petitions filed prior to the November 2018 adaptation of the new final rule. It will also remain the standard for patent reexaminations and reissues.

Because the BRI standard was significantly different than patent claim construction rules followed after the Phillips decision, the U.S. Patent Office changed its rules in order to promote greater consistency and harmonization among different tribunals.

Patent Claim Construction in Federal Court

Although the Supreme Court settled the question that judges are the party to interpret claims, and the Federal Circuit in Phillips and later cases has set forth principles of claim construction, there is little guidance as to when Markman hearings should be held. As a result, there is some difference in opinion across the federal districts as to the timing, although the procedures for this hearing are relatively standardized.

The process for holding a Markman hearing is governed by local patent rules and can differ between courts and even individual judges, although they must be consistent with the Federal Rules of Civil Procedure. Court rules may also be modified for each individual patent case, depending on the complexity of the issues at question.

Occasionally, judges will appoint patent special masters to oversee claim construction proceedings and report back with findings. A judge may appoint a special master in a case involving intricate details in a particular technological field, or simply as a way to streamline a high caseload. Courts may also make use of a technical advisor, whose role would be to assist the judge in understanding technical and scientific vocabulary and theory. The technical advisor must be appointed pursuant to a fair and open procedure, and, like the judge, may not participate in ex parte communication with either party.

Courts typically require the parties to meet and confer outside of court to determine which, if any, claims are actually in dispute. If the parties are in complete agreement as to claim construction, there is no need to go through the claim construction procedure. Even if the parties can agree to the way some, but not all, claims are constructed, the hearing can focus only on the disputed terms, which can save time and money for both sides. Some courts will ask the parties to specifically identify which claims are in dispute, as a way to streamline the case and preserve court resources.

The parties will engage in claim construction discovery, where they will review documentation from the other side relevant to their arguments and defenses. Patent holders may need to provide internal memoranda regarding claims, and both sides may work with expert witnesses to gather relevant extrinsic evidence they wish to utilize in understanding terms.

The parties will typically prepare claim construction briefs prior to the hearing, outlining their arguments. Due to the technical material involved, briefs will often contain images or graphics displaying the inventions in question in order to illustrate their points.

As part of the claim construction process, the parties may submit a “tech tutorial,” in which the parties educate the court on the technology surrounding the inventions. This could be in the form of live presentations by the attorneys or expert witnesses, with questions from the judge, or a judge could request videos from both parties, that he or she will view in private. This video may contain graphics with text overlay and a narration, explaining the relevant technology. Some judges will have the tech tutorial before the claim construction hearing, while others will combine the two events into a single hearing.

Not every case will require a tech tutorial. This will depend on the technology in question, as well as the familiarity of the judge with the material.

Different district courts hold Markman hearings at different points. Some districts, such as the Northern District of California, will have these hearings relatively early in a patent infringement case, prior to the conclusion of overall discovery (although the parties will complete full claim construction discovery) and before summary judgment. Others will have this hearing as an intermediate step between discovery and trial, or even as a step in the trial itself, prior to jury selection.

Some courts, upon reviewing the papers submitted, may decide that this hearing is not necessary at all, and the judge will make an appropriate ruling on claim construction.

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