Confidence with patent documents as a technical resource

What is a patent document and why could it be useful to your R&D team?

A patent confers upon the holder a geographically restricted and time-limited monopoly to exploitation of the invention that the patent defines. In return, the patentee must publically disclose and describe how to work the invention. This disclosure takes the form of a “patent document” (patent or patent application). The publication of the patent document puts a description of the invention in the public domain. A patent document is therefore, among other things, a written record of a technology development.

To be valid as a patent in most countries, a patent document must protect an invention that has not previously been publically disclosed. At the time of filing, at least the information found in a patent document should not therefore be found in a textbook. Indeed, in areas of technology where textbooks are uncommon, it may never be. Patent documents may therefore often provide the only public records of technological developments.

When the patent document is your own, it is a historical record of your own developments. When the patent document belongs to a competitor, it is a record of their developments. In both cases the ability of your scientists and engineers to understand, digest, and learn from a patent document can be an extremely useful resource for an R & D team when doing their own work.

As well as a technological record, a patent or patent application is also primarily a legal document. It is built with its legal purpose and intent in mind: particular parts of the document perform particular functions and have particular legal effects. This is not the place to delve into those functions or effects, and we are not going to do so. The underlying legal reasoning behind the structure should not however diminish the usefulness of the document as a technology record.

Two brief but important caveats:

  1. This guide is not concerned with the legal scope of a patent document – what it “covers” or “protects”. In other words this is not a guide to understanding the legal effect of a patent document, which is a different and considerably more involved process.
  2. Naturally the aim of the patent document is to protect against commercial exploitation of at least some of the information contained in the patent document. One must be careful when using commercially the information from a patent document.

That said, large portions of the content of a patent document are aimed at the technical reader and could be useful to the reader in their own technical work. But how does the reader approach understanding the technical content of a patent document with confidence?

The structure of a patent document

Patent documents usually follow a basic and widely-used structure. Understanding the structure will allow the reader to find the technically useful components, while avoiding becoming bogged down in sections that are unlikely to assist.


This is generally chosen to be (often absurdly) broad and it is rarely informative. For this reason you should not rely on patent document titles to identify useful documents or to understand the contents.


This section is used primarily to enable searching for patent documents and is thus a useful part of the document for finding relevant patents. However, it’s unlikely you will find information in here not stated elsewhere in the patent document, and it’s often more clearly stated elsewhere. The abstract is unlikely therefore to be of much use for the purposes described here, once the document has been found.


This section sets the scene for the disclosure of the invention which follows. The intention is that this section should set out the background to the invention, including relevant technology available before the patent application was filed. In practice the introduction is usually fairly brief, and is unlikely to describe everything relevant that came before the patent document. A granted patent may be slightly more comprehensive than an application in its identification of pre-existing subject matter. However the informed reader may well know more about the technology area than the introduction section describes. Finally the introduction may set out one or more problems that the invention is seeking to address. This may prove useful insofar as patent documents seeking to address a particular problem can be identified from this section.

Statements of invention / general description

This section describes the invention in broad, often generalised, terms. In many cases the wording is a reflection of the wording in the “claims”, which we will come to shortly. Many features in the statement of invention section will also be explicitly described as optional, or at least using language that suggests a particular feature is not essential to the invention. Either way, it is in this section that we get our first insight into what the applicant / patentee thinks the invention is (or was), and any supplementary features or refinements that could be included in the invention. The wording here may make it difficult to understand, on the face of it, what the invention is considered to be.

Sometimes the purported advantages or effects of the invention will be stated in this section. The reader may find this information useful, particularly in combination with the problems to be addressed from the introduction section.

Detailed / specific description & drawings

These sections are where the most useful technical insight is found. Here the reader finds, in specific terms, a description of at least one implementable example (or “embodiment”) of the purported invention. In describing the example, the detailed description usually makes reference to drawings via reference numerals, which should be similarly numbered in the drawings and the detailed description. Supporting data, where necessary, will be found in this section.

The detailed description usually describes the example in specific, unequivocal, terms. The detailed description is consequently easier to understand than many of the other sections. In terms of using the patent document as a technical resource, it is these sections that will prove the most helpful.

It’s worth stressing that what is described in this section are examples of methods or systems that include the invention. The specific examples are rarely the only way of implementing the invention and may well not be the best way to implement the invention.

The reader may also find a detailed description that includes a number of arrangements or features described in the manner of an invention, but which are not apparently relevant to the invention of the particular patent document. This is because sometimes a common detailed description section is used across a number of different patent applications. In other words, a single detailed description is prepared describing a complicated product comprising a number of inventions, and the detailed description is re-used across a set of related but different applications. Each application in the set will be focussed on a different invention of the product. Do not be perturbed. This is irrelevant when using the detailed description as a source of technical insight. Information in a detailed description should be judged on its usefulness to your R&D team.


This is where the patent document is at its most challenging. Luckily when using a patent document for technical insight, the claims are not critical and can often be ignored.

Nevertheless, the claims are where the patentee attempts to define, in words, the boundaries of the invention which is the focus of the patent. The aim of the patentee is to have a claim of broad scope. The language of the claims is usually deliberately selected to be as generalised as possible. For that reason and others, the subject matter that a claim protects and does not protect (the claim “scope”) is often very difficult to determine from the claim wording alone. This makes claims and their scope complicated to assess. It also means however, that clear technical insight is unlikely to be found in the claims – any such insight should be found elsewhere in the patent document in more reader-friendly and technically instructive language.

How to approach reading a patent document

There are any number of ways to approach reading a patent document. Having read a few, everyone finds a way that works for them. As a starting point, this is what I do when I am coming at a patent document totally cold and I need to understand it. Others do it differently and this is not the only way. My focus is usually on the claims, but reading for technical insight purposes should focus on the detailed description. You could use this as a starting point, or blaze your own trail.
  1. Read the introduction and scan over the drawings – what is the field of this invention? What I am likely to be looking at it? Washing lines? Car park layouts? Rain water collectors? What is the problem that the invention purports to solve?
  2. Read the claims – now that I am orientated by the introduction and the drawings, what am I expecting to see defined as the invention? What does the patentee think is new and clever here? Which features should I look out for as being important? Often the introduction and general statements description are useful here too
  3. Read the detailed description with the drawings open in front of me at the same time. I try to tie the written examples to the drawings. How does the example fit within the wording of the claims? Which specific part of the example corresponds to which generic part of the claims? For example, the claims use “covering member”. I have little idea what that means in isolation, however I see in the detailed description that an example of a covering member is a “cap”. Understanding the specific examples allows me to understand the generic claim.
  4. Read the claims again, now that my thinking is anchored in the specifics of the detailed description.

Patent documents cannot generally be read linearly like a news article or a technical journal; some back and forth is required. With a little practice however, patent documents become relatively simple to read and understand. Technical insight quickly follows.

Where can I find patent documents relevant to my industry?

There are many answers to this question. The various options have differing levels of user friendliness, completeness of search, and granularity of search parameters. For important searches requiring confidence in the search completeness, it is always advised to use professional searching services. However there are powerful, free to use, patent document search engines readily available for an initial look. One such search engine is Google patents, which is an excellent place to begin.


Dates and their applications are very important within the patent process. Without diving into the details here, two points are worth making in the context of this article:

  1. A patent application is generally published around 18 months after its filing or its “priority” date, whichever is earlier. Furthermore, a patent is generally published again when it is granted. The grant publication could be several years after the preceding patent application document was written, filed and published. You are therefore unlikely to see a patent document that was written less than 18 months ago, and often it will have been first prepared much longer ago than that.
  2. The legal validity and scope of a patent is assessed, generally, as of the filing or priority date, whichever is earlier. Furthermore, and again generally, it is not possible to add subject matter to a patent application or patent after the application is filed. As such when reading a patent document and considering what it means, you should imagine that today’s date is the filing or priority date. In particular, while we are not considering here the scope of the patent and what it protects, the reader should avoid the trap of reading a patent document and concluding that it describes something entirely conventional on today’s date when actually it was written many years ago when the technology was unknown, and it should be understood as such. Of course the age of the information does not preclude usefulness; technical insight does not necessarily have a useful lifetime.

In conclusion, we have provided some insight into patent documents, and how they might be used as a technical resource. With some practice it should become relatively easy to become acquainted with the technical work of your competitors, or with your own historical developments, using freely available patent documents.

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