Parts of a claim
A patent claim is generally composed of three primary components: the preamble, the transitional phrase, and the body, although the exact structure may vary depending on the jurisdiction and the drafting style of the claim.
Preamble
The preamble is an introductory expression that specifies the category of the invention protected by the claim. For instance, the invention may relate to an apparatus, article, composition, compound, device, system, method, or process.
The preamble is usually drafted as a singular noun phrase. This noun phrase may be preceded by premodifiers, such as adjectives, for example: “a chemical composition”. It may also contain postmodifiers, such as complements introduced by a preposition, for example: “a chemical composition for moisturizing”. The addition of more adjectives or complements progressively narrows the scope of the preamble.
It is essential that the preamble is selected with care and reflects the intended level of breadth. In certain situations, it is advisable to align the preamble with the title of the invention. Although the claim may also incorporate the object of the invention within the preamble, the patent drafter must exercise caution just as when preparing the description (see Module VII) to avoid unintentionally restricting the scope of the invention.
Let’s take a look at some examples to better understand how the preamble functions in practice.
Example 1
A patent applicant has invented a rice cooker. Since an object of this invention is to cook rice, the preamble and title might read:
“An apparatuS for cooking rice,”
Suppose that the patent applicant knows their invention could be used for cooking all kinds of grains. In this case, a broader preamble might read: “An apparatus for cooking grains,”
Suppose further that the patent applicant knows their invention could be used for cooking vegetables - or even melting cheese for fondue. An even broader preamble might simply read: “An apparatus for cooking,”
Example 2
A patent applicant wants to claim a unique method of making tea. Here, the preamble might read:
“A method for making tea,”
If the inventor believes their method would be applicable to making any beverage arising from a plant substance, a broader preamble might read:
“A method for making a plant-based beverage,”
If the inventor instead believes their method would be applicable to making any warm beverage, the preamble might read:
“A method for making a warm beverage,”
The second and third preambles are broader, in some respects, than the first: the second preamble applies to any plant-based beverage, whether warm or not; and the third preamble applies to any hot beverage, whether plant-based or not. The patent drafter may include claims in a patent application based on any or all of these preambles provided that they accurately represent the invention. One potential drawback of using these preambles, however, is that the patent office may determine that multiple inventions are present in a single application and require certain claims to be transferred to a divisional application, which would increase the fees payable (see Module VI, section 11, for more on unity of invention).
The patent drafter must ensure that the preamble properly represents the invention. For example, if an invention is intended to cover “bicycles,” and the inventor believes it can be adapted for all types of non-motorized vehicles, the preamble should be formulated broadly enough to encompass all categories of non-motorized land vehicles. However, it may be advisable to exclude motorized flying vehicles.
It should also be recognized that the preamble does not always receive the same weight during patent litigation as the main body of the claim. In addition, the importance assigned to preambles varies between jurisdictions. In some jurisdictions, courts will evaluate whether the preamble “breathes life” into the claim as a whole. If this condition is met, the preamble will be accorded patentable weight.
Example
An invention comprises a mounting for attaching a telephone to a wall. The patent drafter will be unlikely to claim a telephone as part of this invention, because doing so could restrict the pool of potential infringers to those who sell telephones together with their mountings, rather than anyone who sells only the mountings.
Consequently, the preamble for the mounting could read:
“A device for mounting a telephone,”
In this way, both making, using or selling a mounting device alone and making, etc. a mounting device together with a telephone will most likely infringe the claim.
Transitional Phrases
Transitional phrases used in patent claims generally fall into two categories: open-ended and closed.
Open-ended transitional phrases allow for the presence of additional elements or method steps beyond those expressly stated in the claim. In other words, these phrases are inclusive rather than restrictive. In the United States, for example, expressions such as “comprising,” “including,” “containing,” and “characterized by” are regarded as open-ended. These terms are interpreted to mean “including the following elements but not excluding others.” Among these, “comprising” and “including” are the transitional phrases most commonly used in the United States.
Let us examine a sample claim that employs the phrase “comprising.”
Example
The invention relates to a pencil with an eraser and a light attached to it. A claim may read:
- An apparatus, comprising:
- a pencil having an elongated structure including two ends and a center between the ends;
- an eraser attached to one end of the pencil; and
- a light attached to the center of the pencil.
In this claim, the use of the open-ended term “comprising” broadens the claim scope by allowing for the presence of additional elements or limitations. For instance, this claim leaves open the possibility that the pencil may also include a cap. In other words, an accused infringer would not be able to successfully argue that their product does not infringe merely because it includes a pencil cap.
To reiterate, although in ordinary language the word “comprise” may sometimes be used interchangeably with terms such as “include,” “contain,” “comprehend,” or “consist of,” in patent claim drafting legal certainty generally requires it to be interpreted more broadly as meaning “include,” “contain,” or “comprehend.”
Closed phrases represent the opposite of open-ended phrases. Closed transitional expressions such as “consisting of” restrict the claim strictly to the specifically recited elements; the claim covers only the elements explicitly listed and nothing beyond them.
Example
We might rewrite the previous open-ended example in closed form as:
- An apparatus, consisting of:
- a pencil having an elongated structure including two ends and a center between the ends;
- an eraser attached to the pencil; and
- a light attached to the pencil.
By using the phrase “consisting of,” this claim becomes a closed claim that includes only the three recited elements of a pencil, an eraser, and a light - and nothing more.
A patent drafter may occasionally prepare a claim for a chemical compound that is described as “consisting of components A, B, and C,” with each component defined by its respective percentage. Claims of this type are generally acceptable in most jurisdictions. However, the presence of any additional component is explicitly excluded, which means that the specified percentages must total exactly 100 percent. When drafting such a claim, the patent drafter must clearly understand that third parties may circumvent infringement simply by adding another chemical compound, regardless of how minimal its proportion might be. As an alternative, the patent drafter could ensure that one of the components included in the percentage is defined broadly enough (for example, “metal”) to cover a wide range of substances.
A patent drafter will rarely choose to draft and should think carefully before submitting-a closed claim. The reason is that potential infringers can easily avoid infringement merely by introducing an additional element. In some jurisdictions, however, a patent drafter might use a closed transitional phrase where the invention represents a simplified version of an apparatus that already exists. Because the simplified invention contains fewer elements than the original device, certain jurisdictions may regard a closed phrase
Professional Tip:
Most jurisdictions follow the “peripheral claiming” doctrine, under which the claims define the outer limits of patent protection. Unless an application is filed in a now relatively uncommon jurisdiction that still allows claims based on a “central claiming” doctrine (which identifies the core of the patented invention), it is essential to draft claims that clearly define the exact scope of the protection being pursued.
We previously discussed the open-ended phrase “comprising” and the closed phrase “consisting” as transitional phrases. It should be noted that these expressions may also appear within the body of the claim to define elements either in an open-ended manner or in a closed form.
2.2 Claim Grammar and Further Details
Punctuation:
Although many aspects of patent claims may attract more attention than punctuation, almost every patent office imposes particular requirements concerning it. If a patent drafter concentrates solely on aligning claims with the client’s commercial objectives while overlooking the detailed use of full stops and semicolons, they may discover that otherwise well-prepared claims are rejected by patent offices around the world.
For the sake of clarity, claims are frequently punctuated more extensively than strict grammatical rules would normally require. In general, a comma separates the preamble from the transitional phrase, and a colon often separates the transitional phrase from the body of the claim. The body itself is typically divided into short paragraphs, each describing a logical element of the claim. While many jurisdictions do not prescribe explicit legal rules governing such punctuation, patent drafters should strive to ensure that their claims will be interpreted as intended. The drafter must write with the patent examiner and later, the courts and potential licensees in mind. As a result, the “elements” of a claim are usually separated by semicolons, with the penultimate element followed by “; and,” before the final element ends with a full stop.
The model is this:
Preamble, transitional phrase:
- Element (#1);
- Element (#2); and
- Element (#3).
In practice, it might look like this:
An apparatus, comprising:
- a plurality of printed pages;
- a binding configured to hold the printed pages together; and
- a cover attached to the binding.
In some countries, such as the United States, each element or combination of elements in the claim should be separated by a line indentation, as illustrated here. In certain other jurisdictions, line indentation is permitted but not mandatory.
The Secretariat of WIPO assumes no liability or responsibility with regard to the transformation or translation of the original content. World Intellectual Property Organization (WIPO) (2023). WIPO Patent Drafting Manual, Second edition. Geneva: WIPO. DOI: 10.34667/tind.44657