It is the wording of the patent claims that defines the invention and, in turn, the scope of the patent protection you are applying for. Therefore, it is important that you are careful when you draft the claims.
A patent claim relates to one of the following categories: product, device, procedure or use. Although your application can only contain one invention, you can often use several categories to protect it, as long as the claims are based on the same inventive idea.
For example, if you have invented not only a type of milk packaging but also a method of manufacturing it, you can obtain protection for the method in the same application. The manufacturing method must be defined in a separate, independent patent claim.
Preamble and characterizing portion
The claims should have an opening portion which corresponds to prior art, meaning what your invention has in common with known technology and is based on, and a characterizing portion describing what is new and unusual about the invention.
The patent claims must clearly describe the invention, without having to refer to the description or the drawings. However, to help the reader, you should use numerical references in the claims to refer to any drawings.
Independent and dependent claims
The most comprehensive claim in each category is known as an independent claim. Often, the independent claim only deals with the general principles required for the invention to function in the intended way – the scope of a patent claim becomes narrower the more features that are included. More detailed forms of implementing the invention are described using dependent claims.
A dependent claim includes all the features of a main claim, as well as possibly all the features of one or more other dependent claims. It can be worded: “A device according to patent claim 1 or 2 … ” or “A device according to a previous claim ... ”.
If our examination shows that an independent claim is too general to indicate any patentability, it is practical to be able to incorporate features from dependent claims.
The number of dependent claims needed to protect the invention varies from one patent application to the next, but it is rarely necessary to have more than the ten included in the basic fee.