Patent Drafting for Beginners: A prelude to patent claim drafting

The art of patent claim drafting is an undeniably difficult art to master. It is, however, essential for those in the patent space to both appreciate, understand and master.

Patent Claim Drafting for Beginners: A prelude to drafting a patent claimMost of what appears in a patent application and ultimately in an issued patent does not directly define the exclusive right that has been awarded by the federal government. The right to exclude granted to the patent owner is limited to whatever is defined in the patent claims. It is, of course, perfectly true to observe that the rest of the patent application or issued patent provides critical context, understanding and definition relating to the claimed invention, but at the end of the day the question of infringement asks whether one or more of your patent claims are being infringed. For that reason it is not enough to merely show or mention aspects of the invention in the drawings or specification, but rather you need to have patent claims that appropriately cover your invention. *

The art of patent claim drafting is an undeniably difficult art to master. It is, however, essential for those in the patent space to both appreciate, understand and master. Before we put the cart before the horse let’s take a step back. Given the importance of patent claims it is not unreasonable to want to start there, electing to jump right into the deep end. That would be a mistake. That is not how patent attorneys do it, and if you want to succeed that shouldn’t be your approach either.

Before you ever think about writing patent claims there are several very basic questions must be answered first. They are:

  1. What is the invention?
  2. What are the pieces and parts that make up that invention?
  3. How do the pieces and parts relate to one another?
  4. Do you have more than one invention?
  5. Are there multiple versions of each invention?

The first question is quite basic, but whenever the task at hand is complex it makes perfect sense to start out easy with something that you can accomplish and build from there. Still, as easy as it may be to identify the specific invention you have, it might be far more difficult to identify the invention in a suitably general but not vague way.


Inventions cannot be described in a vague or ambiguous manner, but all too frequently inventors will make the mistake of only describing their invention very specifically. You obviously want to describe in a hyper specific way the version of your invention that you are selling, as well as any versions that you think have commercial potential or might be knocked-off. But you cannot merely describe your invention in a specific way. The goal must be to describe the invention specifically, but to also broaden out to describe and capture the invention broadly.

For example, let’s say you are the inventor of beer mug that incorporates a digital timer. The invention further includes a strong magnet that engages and prevents the container from being lifted from a metal surface until a predetermined appropriate amount of time has passed. The predetermined amount of time is determined via a simple calculator that takes into account the alcohol content of the beverage and the weight of the individual consuming the beverage. The purpose of the invention is to make sure that the consumer of the beverage never drinks too much too fast again, or at least if they do they will be well aware of that fact as they have to pry their beer from the metal surface.

So what is the invention? It is a beer mug, correct? Yes, but it is also much more. Is there any reason that what has been described must be limited to being implemented in a beer mug? No, there isn’t. So a patent attorney would look at this and see a beer mug that needs to be described, but would also generically describe a drinking vessel that may or may not take the form of a beer mug. A patent attorney would probably include various patent drawings that show different types of drinking vessels, maybe even a bottle with a magnet incorporated into the bottom of the bottle so that it too couldn’t be easily lifted. The point is your invention is almost invariably going to be more than you initially think it is, and in almost every case there should be multiple different versions of the invention disclosed in the specification and drawings, and then specifically claimed.

Once you’ve answer those questions above and worked through the variations and permutations you are still not ready to start writing patent claims. More investigation is required.

The patent claims are what patent examiners evaluate when they review a patent application. Patent examiners will compare prior art against the patent claims on file in order to determine whether the patent claims define an invention that is novel (i.e., new; not identical) and non-obvious (i.e., not a trivial combination of known prior art elements). Thus, when drafting patent claims you have several goals. First, you must define a working invention. Second, the invention defined in the patent claim at issue must be novel and non-obvious. From here we will focus on defining an invention that is new and non-obvious.

In order to define an invention that is new and non-obvious you must include something in the claim that is different than what is found in the prior art. Perhaps you are improving the prior art by adding something to an existing invention. Perhaps you have come up with a more eloquent solution that requires fewer pieces and parts, which makes the invention cheaper to manufacture and more durable. Whatever the case may be that best defines your innovative solution, the claims need to define something that is different. The only way to know what needs to be put into a claim to have a realistic chance of convincing the patent examiner that your claims are new and non-obvious is to do a search, which must include both a patent search and a product search on the Internet. For more see Patent Searching 101 and Patent Searching 102.

The goal of doing a search is to find the closest prior art. While I always recommend inventors do their own search to start, at some point a professional patent search should be obtained. Generally speaking for $400 to $600 you can get a high quality patent search by a reputable search company, and they will find a lot more than you will. But do your own search to start. If you can find something that is too close for comfort you might as well save the money.


As you look over the prior art what you want to do is identify the difference between your invention and the prior art. Initially, try and find as many differences as you can. Some of the differences will not be of patentable importance. Inventors love to focus on different uses, but if you are trying to protect a device it doesn’t help that someone has described the same or very similar device to be used differently. If you are trying to protect a device you need to focus on the device, not the use. So identify as many structural differences as you can. Hopefully the differences you identify will be advantages. I always encourage my clients to also ask whether the differences they identify and want to build the patent around are things consumers will be willing to pay a premium to obtain.

Armed with your list of differences you might find it useful to create a chart that compares your invention against the most closely related prior art. I go over this in much more detail in Patent Drafting: Identifying the Patentable Feature.

Up next in this series — Patent Drafting for Beginners: The anatomy of a patent claim.

Additional Information

For more tutorial information please see Invention to Patent 101: Everything You Need to Know. For more information specifically on patent application drafting please see:


* As with most things in patent law, what I’ve already written could be expanded into an entire chapter, if not an entire treatise. But for now let’s leave it that. Patent claims must appropriately cover your invention. What that means is and how it is done takes us well beyond this primer on patent claim drafting. For more please see our articles tagged completely describing an invention.


Warning & Disclaimer: The pages, articles and comments on do not constitute legal advice, nor do they create any attorney-client relationship. The articles published express the personal opinion and views of the author as of the time of publication and should not be attributed to the author’s employer, clients or the sponsors of

Join the Discussion

8 comments so far.

  • [Avatar for Ian Forbes]
    Ian Forbes
    December 7, 2016 06:22 am

    Thank you for the great information. Definitely has cleared up some questions and roadblocks in my head. Never quite enough time in the day and your posts have helped me immensely in expediting the already long “drawn out” process of filing and patenting. Thank you, I look forward to being able to purchase a couple of the mentioned resources. Thanks again.

  • [Avatar for Eric Berend]
    Eric Berend
    November 1, 2016 06:01 am

    @5., Gene:

    Thank you for making mention of this particular course. When it is ready, I would be quite interested in attending.

    @6., Steve:

    Thank you for a very good checklist of essential tasks for the resource constrained inventor. This is not too dissimilar to the situation in which I was forced to defend a leasehold against a wealthy landlord as pro se: study-study-study (but, must be enough of the right sources); study some more; draft, revise, revise; have each paper reviewed by at least one attorney before filing and serving notice.

  • [Avatar for Steve]
    October 31, 2016 09:01 pm

    Gene — if I may make 5 save-money-while-getting-all-you’re-entitled-to suggestions:

    1. Buy and use the most current (18th Edition) of David Pressman’s excellent Patent It Yourself book. It’s what I used to file and prosecute my 1st app way back in 2000.

    2. Buy and use Gene’s Invent + Patent System.

    3. Buy and use Ron Slusky’s Invention Analysis and Claiming book.

    4. Beg, borrow, sell your blood; whatever it takes; to hire Gene or other excellent prosecution attorney to review you application BEFORE YOU FILE IT WITH THE PATENT OFFICE.

    5. When you receive your rejection from the Patent Office (and your application will be rejected), have Gene / your patent attorney either write the response; or at least review it BEFORE YOU FILE IT WITH THE PATENT OFFICE.

  • [Avatar for Gene Quinn]
    Gene Quinn
    October 31, 2016 10:05 am

    Lost in Norway-

    I know the feeling about working with inventors who refuse to cooperate. I’m at the point where I won’t represent inventors like that any more. You can lead the horse to water but you just can’t make the horse drink I suppose. In the past, however, when I’ve had particularly stubborn inventors the way I’ve finally managed to get across to them was to explain in writing what they were telling me and that they had instructed me to intentionally give up scope they may be entitled to patent and that if someone were to make one of the “inferior” versions of the invention that was not worth protecting that they would have absolutely no ability to stop them.

    Generally these stubborn inventors are arrogant and condescending. They think they know everything and believe the patent attorney or agent just doesn’t understand their invention. So if you get caught working for someone like that and you can’t get out I’d make sure you CYA by explaining everything in very easy to understand language. Make it clear the inventor has instructed you to only protect one very narrow and potentially quite useless variation of the invention while not describing any other possible variation.

    As for office actions, I don’t have anything like that. I hope to soon have a course for new patent agents and attorneys, which could also be used by serious individuals. It would show them soup to nuts how to do everything so they at least see as many possible procedural situations.


  • [Avatar for Lost In Norway]
    Lost In Norway
    October 31, 2016 03:22 am


    I have some inventors that just want me to write the claims. While not ideal, it is better than them writing the claims by themselves. A good set of claims and a few pointers on how to change the spec to support them can payoff big for an inventor. But many of them do not have the budget for me to write the office action replies. I know you have given this advice several times in your articles.

    Do you have any articles on how an inventor, representing themselves, can make sense of the office action and formulate a “decent” reply? I have found that about 3/4 of an office action is often worthlessly filled with form paragraphs that are not understandable by the average inventor.

    It is not that I want to lose business, but I want these single inventor startups to succeed.

  • [Avatar for Lost In Norway]
    Lost In Norway
    October 31, 2016 03:19 am

    I had an inventor recently that just wouldn’t tell me what the minimum needed to perform his invention. I swear, each time I asked I was told the story of why this was the best mode. That anything other than this configuration wouldn’t work well. In the end I guessed that only 5 elements out of 20 were in fact essential for bare utility. Now I await the office action and the inevitable 102/103 rejections.

  • [Avatar for Benny]
    October 30, 2016 05:25 am

    Would not widening the scope of the claim beyond containers intended for alcoholic beverages defeat entirely the purpose of the invention, as Gene described it? (preventing intoxication)
    Note that a similar granted claim found in a brief search provided a list of possible containers, including “cup, mug, travel mug, baby bottle, beer mug, carafe, or liquid container”

  • [Avatar for Peter Kramer]
    Peter Kramer
    October 29, 2016 09:55 pm

    When I saw “drinking vessel” it reminded me of that ending line from Throw momma from the train: “It was sultry.” I wrote an application years before using a much more cumbersome expression in the abstract. The current abstract for the divisional application now reads, “drinking vessel.” It was Enrico Fermi who said he liked to teach introductory physics so he wouldn’t forget the basics. Even if experienced, anyone can benefit from looking at an introductory article every now and then.