How can you write the patent claims yourself?

This article describes one potential process, from idea to patent, and explains how you should write patent claims.

  • They are difficult to write, read and understand
  • They are expensive to have written by professionals
  • They mean everything in a court case
  • They are found in all patents

I am of course referring to the "patent claims" – the very foundation for assessing any patent application. 

After many years as a patent examiner at the Patent Office, I have seen how difficult it is for inventors to succeed. In this guide, I reveal some of the tricks you should know if you're writing on your own (and what a cabin trip in 1960 can lead to...). 

Before we draw anything up; think back to a winter's day in 1960 - before the "knipetakene" (a type of wheel clamp used for driving in the snow) had been invented. The snow is falling. You drive to the cabin. On the last hill, the car is stopped by deep snow. Chains, you think... After a lot of rooting around, the chains are finally on, but you still can't get up the hill! 

Realize the problem with the old product

You get annoyed and realize that the chains are not suitable for deep snow. Assembly is difficult and the result is poor. 

Determine your idea to solve the problem

At the cabin, you ponder the inadequacy of the chains. The problem can perhaps be solved by eliminating the chains? Being the inventor that you are, you come up with a brilliant idea! To the wife, you explain it like this: "a claw that can be threaded onto the wheel and quickly tightened with a handle". Such a device would probably be suitable in deep snow and would be able to solve the problem.

Find all solutions to the idea

Once at home, you have developed a solution in principle on paper. You make a prototype, and feel proud after trying it. Your colleague has become curious about the way it works. Over the phone, you explain it like this: "four gripper arms pull against each other and tighten over the wheel when you turn a gear that is in contact with the gripper arms". This became unclear to the colleague... Where is the gear located? Why does the gear rotate? How can the arms shift? You realize that this was an inadequate recipe for your invention. In order to get a better overview, you would rather listeach element of your device, one by one, , and only the mandatory and indisputable facts about its construction (see figure): 

grunderhjul_patent example.jpg
"Anti-slip device for vehicle wheels" has been patented in several countries.
  • the gripping arms (16) are displaceably stored in a housing (5)
  • the housing (5) is central in relation to the wheel (14)
  • the gripper arms (16) have a gripper (10) at one end
  • the gripper arms (16) have teeth (4) at the other end
  • the gear (7) is stored in the housing (5)
  • the gear wheel (7) is connected to the gripper arms' teeth (4)
  • the gear wheel (7) is rotatable by means of a handle (13)

In order to prevent imitations that attempt variants of your basic idea, you think through practical and possible alternatives of the solution. You then realize that four gripper arms are preferable, but that two or more than four are also possible. You do not consider the additional gripping device (20) to be necessary to solve the task, but as advantageous. The same will be true for the handle (13), which is springy and can be attached to the gripper arms (16). You do not include such features in patent claim 1.

Only now are you ready to shape patent claim 1, which will define the invention in its broadest scope. Remember that patent claim 1 must stand on its own two feet, be independent, and that the text in its entirety defines what is sought to be protected!

Formulate the term

The first words in patent claim 1 must tell what this applies to. You should avoid words such as "grip bars" which indicate the novelty, "car wheels" which in principle only apply to cars, "clamp roof" which is a trademark, "snow" which excludes sand, or "capable of use in deep snow" which indicates the new the impact. I suggest you write "anti-skid device for vehicle wheels". This designation is short, factual and understandable for everyone, is assigned to the category "devices", and generalizes by using expressions from the nearest superior technique.

Formulate the known

This part of the patent claim must explain which technical features of your invention were known before you applied for a patent. It is like conceding that parts of your invention were actually known, so that it will be easier to determine what in particular is new about the invention. Usually, the closest patent document is used to determine what is conceded to be known about your invention. 

Your familiar starting point is "chains". Since "knipetak” do not relate directly to chains, you cannot use "chains" directly in the claim, but you must generalize. I suggest the wording "a member with gripping means which is attachable around the wheel to increase friction against the ground", which is also valid for your embodiments. 

This formulation tells what is common to chains and “knipetak” , but only what is mandatory for the invention to constitute a working solution to the problem. Otherwise, you will overdetermine the patent claim and weaken the patent. Specifying "organ of steel" instead of "organ" can in principle be avoided with materials other than steel. 

Formulate the new

This part of the patent claim usually begins with the words "characterized by". It is then necessary to formulate the new and general principles that are necessary for the invention to work and solve your problem. The term "principle”  refers to the technical means that directly contribute to the solution of the problem. If there are alternative solutions (i.e. embodiments) of your invention, these must be generalized here - and then specified in patent claims 2, 3, 4, etc. Prerequisites for the invention to work and solve the problem, you have mostly listed already in the section on solutions. You can combine some of the elements where appropriate. Remember to generalize the number of gripper arms, which could be two or more. For example, use "at least two". 

Patent claim 1

By combining the terms, the familiar and the new, you get: 

1. Anti-slip device for wheels (14) for vehicles, in the form of a body with gripping means that can be attached around the wheel (14) to increase friction against the surface (21), characterized in that at least two gripping arms (16) are displaceably stored in a housing (5) which is central in relation to the wheel (14), that each gripper arm (16) has a gripper bar (10) at one end and teeth (4) at the other, that a gear (7) stored in the housing (5) is connected to the gripper arms' teeth (4), and that the gear wheel (7) is rotatable by means of a handle (13).

Patent claims 2, 3, 4...

These are embodiments or clarifications that indicate further features of what is stated in patent claim 1, and shall refer directly or indirectly to patent claim 1. These non-independent claims will therefore describe elements of the invention which are admittedly not mandatory, but which indicate various advantageous embodiments. They will constitute withdrawal claims if patent claim 1 is attacked. Look at the figure and list elements that may be new, for example:

2. Anti-slip device according to claim 1, in that four gripper arms (16) are used so that they form a cross after mounting on the wheel. 

3. Anti-slip prevention device according to one of claims 1-2, in that each gripping arm (16) is equipped with a further gripping element (20). 

4. Anti-slip prevention device according to one of claims 1-3, in that the handle (13) comprises a spiral spring. 

5. Anti-slip prevention device according to one of claims 1-4, in that the handle (13) can be attached to one of the gripping arms (16). 

The trip to the cabin provided you with the problem. Then you came up with the idea, then came the solution, and now you have designed the patent claims. The latter will be a natural starting point for formulating the rest of the patent application. If you are successful with your own efforts, you have created the conditions for a quick decision on the application. In the best case scenario, you can get a patent as early as one year after you have submitted the application. Finally, you should know that you have everything to gain from the fact that the patent claims neither cover more – are wider – than what there is a basis for, nor cover less – are narrower – than what you have the right to have protected. 

Content of the patent claims

  • Use the simplest form of language possible
  • Describe the means - not the effect or what is achieved (which does not state the new technique used).
  • Avoid indefinite words.
  • Use general words like "fastener" rather than specific words like "screw".
  • Describe solutions – not the task.
  • Use unambiguous terms.
  • Use the usual and most familiar meaning of words.
  • Use a seperate dependent claim for each additional feature 
  • Independent claims must give an independent technical meaning without the need to look at drawings or description for understanding - therefore avoid "as described" or "as shown in figure 2".
  • Avoid relative terms such as "wide" and the like unless these words are well-known terms within the subject area in question.
  • Avoid denials.
  • Avoid advantages/disadvantages.
  • Avoid descriptive text.
  • Fewer details generally provide better protection against counterfeiting.

The form of the patent claims

  • Each claim is written as a single sentence - as all of the features together define the invention. 
  • "Characterized by" is written in block letters. 
  • Use the active form - for example "is". 
  • Use numerical references to the figures to facilitate understanding - for example "organ (4)". 
  • Use the same designations/number references for the same parts. 
  • Definite statements must be preceded by thea statement using the indefinite clause. 
  • Use the same designation in independent and non-independent claims. 
  • Avoid text in brackets. 
  • Dependent claims must always refer to one or more other claims. 
  • Number the claims in order 
  • Type the claims on a separate sheet of paper