The claims of utility patent set the metes and bounds of protection for the invention. They define an intellectual space. If a competing product is inside of that space, it will infringe the claims of the patent, while competing products outside of the space will not. There are essentially two types of claims, independent and dependent, and every patent must have at least one independent claim.
Independent claims define the very periphery of the protectable intellectual space, that is, the outermost boundary. Furthermore, it is permissible for a patent application to include more than one independent claim, though those multiple independent claims can still only define one patentable invention. Dependent claims must always, by law, be inside of that outermost boundary. They must further limit the independent claims.
An example independent claim might state, “1. A table having a top connected to a plurality of legs.” A dependent claim, which further limits that independent claim, would state, “2. The table of claim 1, wherein the plurality of legs is four legs.” Notice how the dependent claim, claim 2, explicitly refers back to claim 1. By doing this, that dependent claim can properly be understood as meaning, what is claimed is everything from claim 1, and additionally, wherein the plurality of legs is four legs. As such, claim 1 requires a table top and a plurality of legs (e.g., two, three, four, five, or six, etc.), while claim 2 requires a table top with exactly four legs. Claim 2 is much more limited, but is still within the space created by claim 1.
When drafting claims, this architecture should very strongly be utilized. If an aspect of an invention is not truly part of what makes it novel, then including that aspect in an independent claim is shortchanging the inventor by making the outermost boundary of protection smaller than what the inventor may be entitled to. Of course, the inventor/attorney do not know everything that comprises the prior art, what is on the outside of the boundary and what the patent will be measured against. However, based on their knowledge, it is critical that the independent claims that are drafted be as broad as the prior art admits. For this reason, the independent claim should be drafted to include the main essence of the invention, and not much more. While articulating that essence may require giving context to the invention, for example briefly including elements of an automobile like an engine and a chassis when claiming a specific feature of that automobile, it should not require giving all aspects of the invention.
Specific aspects of the invention, those that the inventor believes do not truly define its essence, ought to be saved for a dependent claim. By structuring the claims in this manner, the applicant is essentially telling the patent examiner that those aspects do not define the outermost boundary of the intellectual space he or she has invented. Now, if a patent examiner shows the applicant prior art technology that fits anywhere within that outermost boundary, the applicant may be forced to change the size of the boundary by amending the claims. If the claims are structured right, inside of that outermost boundary will be all of the aspects that the inventor initially believed should not define the outermost boundary. By having the additional aspects, or, dependent claims, properly layered inside of that boundary, that applicant can also get the patent examiner’s opinion on them without additional communications, which would require more time/money. That is, though the patent examiner believes that the independent claim is taught by the prior art, does he or she believe any of the dependent claims are? Patent examiners are under an obligation to give an opinion on all of the dependent claims. As such, if the patent examiner indicates that the independent claim is taught by the prior art, but that one of the dependent claims is not, then a simple amendment to the claim language would almost certainly result in an allowance. This type of an allowance may be very desirable for the client.
It is in these dependent claims where often the true, articulable invention lies, and where allowable subject matter can be found. Patent examiners are generally reluctant to allow broad independent claims when they first review a patent application, although it does happen from time to time. For more on whether this is actually a good thing, please see my post entitled Is getting a Notice of Allowance from a patent examiner in the first response a good thing?
This article was authored by John P. Powers, and is intended to keep readers current on matters affecting intellectual property and is not intended to be legal advice. If you have any questions about its content, please leave a comment below.
©John P. Powers, 2020, all rights reserved.