Claim Construction:  a Key Stage of Patent Infringement

In determining whether there has been infringement of a patent, the court must first determine what the patent at issue covers. 

Patents are essentially a limited monopoly granted by the government which allows an individual or entity to have the exclusive rights to make, use, sell, offer for sale, or import a particular invention for between fourteen and twenty years (depending on the type of patent).  Just as most people do not like the board game by the same name, our society disfavors monopolies.  As a result, one of the first steps in a patent infringement case is determining exactly what the protected invention covers so that the patent owner is not given a larger monopoly than it is entitled to. 

Determining whether the defendant’s product infringes the patent is determined by the jury.  However, this first stage of defining what is covered by the plaintiff’s patent is determined by the judge.  The judge looks at the patent in question and will construe or define various words or phrases used in the patent, to determine their meaning in the context of the present lawsuit.  This process is called “claim construction.”  The way in which the judge construes the various words or phrases in the patent will determine what the jury will later compare the defendant’s product to when deciding whether there has been infringement.

The court does not have the time or resources to define every single word or phrase in the patent, and judges do not like to expend effort on needless tasks.  As a result, the claim construction process will often start with the parties exchanging a list of words or phrases among themselves that they feel are in dispute or need to be construed by the court.  The parties will then also exchange their proposed construction or definitions of those words/phrases.  In general, if the parties can agree on what a word or phrase in the patent means, the court will usually adopt the agreed-upon definition. 

After the parties have narrowed down which words or phrases are still in dispute, each of the parties will then submit a brief to the court which explains the legal and factual arguments for why the particular words and phrases should mean what that party says it means.  The court will then review all of the information and issue a claim construction order setting forth the construction of the terms at issue. 

In construing the various words and phrases in a patent, the court attempts to determine what a particular term would mean to a “person of ordinary skill in the art.”  In other words, the court tries to determine what it means to someone in that particular field.  For example, if a patent is for a heart pump the court will look at the term “valve” used in the patent from the point of view of someone who makes or designs heart pumps, and not from the perspective of a person who makes brass instruments. 

Claim construction is a very technical and vital part of a patent infringement case as it sets the stage for the rest of the litigation.  The construction of the various terms in the patent can sometimes determine the outcome of the case or at least narrow the scope of the litigation.  The plaintiff will want the terms construed as broadly as possible to encompass the defendant’s product while still being valid.  The defendant will want the terms to be either construed so narrowly that it does not encompass its product or construed so broadly that the plaintiff’s patent is found to be invalid. 

If you think someone has infringed your patent or if someone has accused you of patent infringement, contact the experienced attorneys at Goosmann Law Firm, PLC, in our Sioux Falls law firm, Sioux City law firm, or Omaha law firm. For more information on patent law, check out this Patent Law 101 blog.