What is a claim?
Every patent must contain at least one claim. The claim(s) appear at the end of the patent, after the detailed description of the invention and any accompanying drawings or figures. In utility patents, it is common to include a number of claims describing different aspects or embodiments of the invention.
The claims of a granted patent are important because it is the claims that define the exclusionary legal rights of the owner. That is, the owner has the right, through litigation, to prevent others from making, using, importing or selling the invention which is described by (i.e., “within the scope of”) any claim of the patent. Just as a deed to a piece of real estate defines the outer boundaries of the land owned by a person (the “metes and bounds”), a patent claim sets parameters on what the patent owner can block others from practicing. Thus, a claim that includes the minimal number of limitations that differentiate the invention over what was already known will be more valuable than a claim containing more limitations, since a broader field of exclusivity will be afforded if the claim scope is less limited.
Why does the law require that a patent include one or more claims?
As mentioned above, the claims of a patent define what the inventor has invented and the legal rights that have been conferred upon the inventor. Claims thus put the public on notice of what can or cannot be practiced without infringing upon the inventor’s right to exclude others from making, using or selling his or her invention. Because of this, the wording of a claim is required to be sufficiently precise and definite to permit others to understand its scope.
What form must a claim take?
Each claim must be a complete, single sentence. The claims section of a patent begins with a heading such as “What is claimed is:” and is followed by individual, numbered claims. Typically, the broadest claim of a patent appears first as claim 1.
What are the typical parts of a claim?
A claim generally contains three parts: preamble, transition and body. For example, a claim may recite “A formulation comprising A, B and C.” “A formulation” is the preamble, “comprising” is the transition and “A, B and C” is the body.
The preamble names the subject matter of the claimed invention. In some but not all cases, the wording of the preamble may be interpreted to limit the scope of the claim.
The transition functions as the link between the preamble and the body and helps to define the breadth of the claim. The transition term “comprising” provides the broadest scope since it is open-ended. That is, a product that contains components or elements in addition to those specifically named in the body of the claim will still be considered to be covered by the claim. Thus, “comprising” can be understood to mean “including at least the following elements.” In contrast, the term “consisting of” is close-ended and narrows the claim scope. Generally speaking, if an additional component is present in a product that otherwise contains all the components listed in the body, the product will not literally infringe a claim containing the transition “consisting of.” “Consisting essentially of” is another transition that is sometimes used. This transition is intermediate in scope and only excludes additional components that would affect the basic and novel characteristics of the subject matter being claimed.
The body of the claim describes the various features and characteristics of the invention that distinguish it over the prior art. If the invention is a composition, the body may list the different components of the composition. For a process invention, typically the body will describe the steps of the process. In the case of an apparatus, the body will include a description of the elements of the apparatus and how they interact or cooperate. If a claim defines only a function of a device or the result of a process, it may be objectionable on that basis alone.
What is an “independent” claim? What is a “dependent” claim?
An independent claim is a claim that stands on its own, i.e., one that does not refer to any other claim. The first claim of a patent will always be an independent claim. A dependent claim is one that does refer back to a previous claim and must further limit that previous claim in some way. A patent is infringed if an accused product or process falls within the scope of a single claim of the patent. Patents typically contain more than one claim. Often this is because the patent owner wants to guard against the possibility that a court may find a single broad claim to be invalid; the court may be willing to find that certain narrower claims are valid and infringed. Also, in some cases a patent may contain more than one type of claim (e.g., claims to a composition as well as claims for methods of making or using that composition).
Can the scope of a claim extend beyond its literal language?
Yes, under some circumstances. To protect a patent owner against copyists who appropriate the benefits of a patented invention while somehow operating outside the literal scope of the patent claims, courts have developed an equitable principle known as the “doctrine of equivalents.” Under this doctrine, the substitution of an element or component that is different from what is specifically required by a claim may nonetheless be found to infringe that claim if the substituted element or component is not substantially different than the claim element for which it is substituted. However, the literal scope of a claim cannot be stretched to include what was known in the prior art or what the patent applicant during examination explicitly or implicitly acknowledged to be different than, or not part of, the claimed invention.
What is the best way to understand how a patent claim should be written or what a patent claim really covers?
Although the basic principles mentioned above may be helpful in understanding patent claims in a general way, it is strongly recommended that the services of an experienced, qualified patent attorney or agent with a technical background in the field of the invention be utilized.
