Claim Drafting

Drafting claims (apparatus)
Two types of patents exist - method and apparatus. The projects of this module will fall under apparatus, that is, inventions that are novel and patentable due to their structure and workings.

Make a list of all of the parts of the invention. You should already have a diagram of your invention with all of the parts listed and numbered (similar to the preferred embodiment in a patent)
Divide the list into two groups: essential and nonessential parts
- essential parts- These parts are required for the minimum functioning of the device. The novelty will rest in these parts. The independent claims will consist of a list of these parts.
- nonessential parts - These parts augment the functioning of the device, but are not required for minimum functioning of the device. These parts, alone or in combination, will form the dependent claims.
Pick an order in which to list the essential parts of your invention. This will depend on the logical workings of your invention. It might be easier to list your parts from top to bottom, left to right, or from inside to outside!
Once you know what parts you will be listing and the order in which you will be listing them, it is time to draft the claims.
There are two ways to describe a structure of group of parts in patent law: explicitly and implicitly. Explicit descriptions will list all of the parts and their relations(see definition of comprises). This gives little patent protections, since substituting two new parts for a listed part will be considered novel. This approach is used when a specific configuration of parts is necessary to be considered novel compared to the prior art.
The alternate way is to describe a set of parts or a subsystem broadly, specifying what is to be done, but not the exact manner in which it is to be implemented(see definition of means) A valve, rather than specifying what type of valve to be used, may be specified as a “valve means.” This will cover ball valves, reed valves, pressure valves, and any other type of valve (including those yet to be invented). The prior art will also have used this strategy, making it difficult to use this approach for all subsystems of your invention.

Things to remember

A claim is one grammatically correct sentence! (which is sometimes hard to believe when a claim covers half of a page in some patents)
When applying for a patent, the Patent and Trademark Office charges for every claim filed over 20. This may seem like a lot of claims, but in reality many patents, even for simple devices, run over 20 claims.
To ensure the novel features of your invention are covered in a sufficient manner, it is usually necessary to draft around three independent claims to cover your invention, usually in increasing detail. One independent claim will generally cover the invention, the next more specific, and the last the most specific of the three. If the patent is issued with all of the independent and dependent claims, your invention will be covered by all three claims, securing protection for the general idea as well as the more specific versions (making it harder for anyone to directly copy your idea) This also allows coverage for your invention if the examiner feels one of the independent claims is too broad(meaning that claim and all dependent claims are not suitable for submission with the final version of the patent.)
The dependent claims, covering the specific nonessential parts of your design, may be the same for each of the three independent claims. The dependent features will then be covered for each of the independent specifications.
It is not necessary to follow these guidelines when drafting claims, but it is helpful. This method is used in practice by patent attorneys and patent agents when preparing patent applications for their clients.
The three patents listed with the “Tire project” show different methods of claim writing.
1. The first patent uses two independent claims(claim 1 and claim 3) covering the invention with the second claim covering the invention in more detail. The dependent claim 2 clarifies some of the structure in independent claim 1. Dependent claims 4, 5, and 6 are not copies of the first dependent claim. Since independent claim 3 is more detailed than independent claim 1, there are three dependent claims following which specify structures listed in independent claim 3. In this case, the second independent claim is so much more specific than the first, a new set of dependent claims is needed. There are two possible reasons for the brevity of these claims.
  1. The author of the patent felt the design would be adequately protected in six claims
  2. There were more claims, but the patent examiner handling the case felt they were not novel and read on previous patents. The author and examiner agreed that removal of these claims would make the invention novel and patented it as such.
2. The second patent uses two independent claims(claim 1 and claim 18). The dependent claims following independent claim 1 are the same as those which refer to independent claim 18. While claim 18 is more specific than claim 1, they are enough alike that the dependent claims following each may be reused. The invention is covered basically and specifically, with the nonessential parts of the invention being included in both cases.
3. The third patent will be discussed when the entirety of the patent is entered.

Return To Environmental Model Syllabus