In 2021, the United States Patent and Trademark Office (USPTO) granted over 374,000 patents. That number may seem high, but it is only a fraction of the number of active patents. As of 2020, there were over 3.3 million patents in force in the U.S. In 2004, there were 1.6 million patents, which means over the course of just 16 years, the number of active patents in the U.S. more than doubled. Infringement in a space saturated with patents is inevitable. Accordingly, there are 3,000-4,000 new patent litigation cases filed in district courts every year.

Patent Claims and Litigation

Patent applications filed with the USPTO must include claims that particularly point out and distinctly claim the invention that the patent protects. Patent claims should outline the scope of protection so that there is a clear delineation of what aspects of an invention are protected and cannot be used without permission. However, those lines drawn by the claims are not always as clear as one might hope.  When a patent holder believes that someone else is making, using or selling their patented invention, litigation provides an avenue to seek a resolution.

Patent litigation is the process used when a patent holder wants to pursue legal action against the entity they believe is infringing on their patent. If infringement can be proven, the patent holder may be able to obtain monetary damages and an injunction to stop further infringement.

The Role of Claim Construction

An infringement analysis has two parts.  First, the claims must be properly construed.  Second, the accused device is compared to the properly construed claims. Ideally, claims are given their plain and ordinary meaning, however in many cases the parties disagree on what the plain and ordinary meaning actually is.  When this happens, the court determines what the claims mean.

Before the court makes their determination, both parties in the case present what they think the disputed terms should mean and the basis for their opinions. They typically use a combination of intrinsic and extrinsic evidence.  Intrinsic evidence shows what the patent holder intended with their invention, and it includes the patent application and communications with the patent office during prosecution.  Extrinsic evidence is generally less preferable than intrinsic and is often only used if there is not enough intrinsic evidence to support the case. It includes evidence like informational references and expert testimony. Some courts use a more holistic approach to evidence, choosing to forego labeling evidence and instead have both parties present whatever evidence is relevant. Regardless of the approach, the evidence presented can have a significant impact on the judge’s decision.

Expert testimony can be of particular importance during claim construction as claim terms should be given their plain and ordinary meaning as it would be understood by a person of ordinary skill in the art at the time of the invention.  A person of ordinary skill in the art is usually referred to by an acronym: POSITA, POSA, PHOSITA, etc. Certain terms may mean something different in a technical field than they would to a lay person.  For example, the term “moment” to a layperson may refer to a point in time, while to a mechanical engineer a moment is a force multiplied by a distance.  As such, patent terms need to be examined through a particular lens. It may not be enough to have any medical expert involved in the claim construction of a medical tool or any engineer to work on a consumer product. The expert must be able to offer opinions on what a person of ordinary skill in the art would have understood.  For example, a dermatologist probably would not be a person of ordinary skill in the art for a patent for a new laparoscopic tool, nor would it be likely that a software engineer was a POSITA on a patent for a magnetic tool tray.  The level of ordinary skill is dependent on the patent at issue, and is important to understand at least for the vantage point from which to view the technology and descriptions in the patent.

Markman Hearing

A Markman Hearing, or claim construction hearing, can be ordered by the court at any point before the patent infringement trial. This is when both sides’ arguments on claim construction will be heard. Clarity and thoroughness is important during claim construction to ensure that the judge understands the issues and arguments for or against a certain construction.  The court will typically issue an order on claim construction based on the Markman Hearing.  The court may agree with one of the sides proposed constructions, decide that the term doesn’t need to be construed, or provide their own independent construction.  However they decide, the Court’s claim construction is the true and proper meaning the construed terms should be given in any further analysis in the case.

The Case Within the Case

As claim construction is the first step in an infringement analysis, it can be critical to the case to have the court agree with your construction.  In order to do that, experts often write declarations on claim construction, have their depositions taken and sometimes even testify in the Markman Hearing.  Some cases never move past the claim construction phase, as the initial infringement contentions are no longer credible based on the Court’s construction of the claim terms.  Other cases do continue to determine infringement.  In those cases, experts write additional reports regarding infringement and invalidity, often get deposed and testify in a courtroom a second time, all for the same case.  A large percentage of patent litigation cases are won or lost based on the quality of claim construction.


Alpine Engineering & Design, Inc. offers claim construction services for mechanical engineering patents. We have a depth and breadth of knowledge that will provide a unique edge to your patent infringement case. Whether you are involved in patent litigation involving consumer products, gizmos, gadgets, tables, chairs, hydraulic equipment, conveyors, or other mechanical engineering parts or equipment, we have an expert who can help. Call us at (801)763-8484 to learn more about our claim construction services.