On first glance, patent specifications can be daunting. Here we explain the content of each section, and where you need to look to find the information you need.


Most patent applications follow a similar structure and contain the following sections.

Field of the invention – this is a brief description of the type of invention the patent relates to (e.g., a fuel formulation, a method for reducing particle size, etc.). 

Background to the invention – this provides an outline of the prior art of which the patentee is aware, usually with an indication of its disadvantages which the claimed invention purports to overcome. It sets the scene for the invention. It may be a useful source of relevant art when assessing claim validity, though the patentee is not obliged to be accurate or complete in their review of the art.

Statements of the invention – these are formal definitions of what the patentee believes they have invented and the scope of monopoly sought. They are analogous to the “claims”, and indeed often use very similar wording. The statements should usually include the broadest definition of the protection sought, corresponding to the main claim(s), along with optional features (often referred to as “preferred” features, even if that is not strictly true).

Brief description of the drawings – this one is simple – a list of the drawings contained in the application, with a brief outline of what each one shows.

Detailed description – this describes one or more examples of how the claimed invention might be put into effect (sometimes referred to as “specific embodiments” of the invention). It should describe at least one version of the invention sufficiently clearly and completely to allow others to reproduce it and provide adequate support to justify the claim breadth. 

Examples – the detailed description often includes worked examples, for instance preparation and testing of claimed materials, etc. Comparative data may be quoted to highlight distinctions between the prior art and the claimed invention. These parts are not strictly relevant to claim scope although naturally they might give pointers as to whether the claims are novel, inventive and adequately supported.

Claims – the claims define the scope of protection desired. The “independent” claim(s) contain the broadest definition(s). The “dependent” claims define progressively more limited versions of the invention, with more distinguishing features. If you are reviewing a patent application prepared for your invention, look carefully at the claims and make sure they provide coverage for all possible versions of your invention, including those you might not have made yet. Will they allow you to keep third parties far enough away?

Abstract – a summary of the main features of the invention(s) described and claimed in the specification. Its purpose is primarily as a searching tool.


Scientific Information

If the patent specification is being used as a source of technical information only, then attention should be focused on the detailed description section of the patent specification. As mentioned above, this may comprise one or more “examples” which describe precisely how the invention has been carried out.

In the case of a new material, for example, an example should include precise details of everything done to make that material (temperature, times etc.). It will usually have levels of detail at least equivalent to, and frequently in excess of, that found in a paper. The level of detail is high because the patent specification must satisfy the “sufficiency” requirements of the patents acts and laws. 

This section may also include specific data, showing key properties of products or processes. Obviously, this information is often commercially important and so some specifications keep this information to a minimum. On occasions however, it is possible to spot key areas for a company from the data given in a patent specification.

It is important to stress, however, that the detailed description section will generally focus on particular embodiments of what the applicants consider is their invention. The scope of protection is usually broader than these examples.

Scope of protection

If you are trying to determine what the patent encompasses, for example in order to decide whether an action you might take is likely to fall within the scope of the patent, then you should start with the claims. The claims define the boundaries or the scope of the protection given by the patent. If an activity falls within the scope of any claim, (i.e. includes at least all the features listed in a particular claim) then it is likely to be considered to infringe the patent.

We’ll be looking at freedom to operate and infringement in a future briefing. Claim interpretation and infringement are complicated questions, though, so if you are concerned about whether your proposed activity falls within the scope of a patent, or whether a third party’s activity will be covered by your patent, we strongly recommend talking to your patent attorney. If you would like to speak to us about it, please contact any member of the patent team.

This is provided for general information only and does not constitute legal advice.