Patent Drafting: Drilling Down on Variations in a Patent Application

The goal of a patent application is to teach others how to make and use the invention. But why would an inventor want to describe their invention to the point where others could simply copy them? The simple reason is that the US patent laws require such a description. The more complete answer is that such a description is required because in order for the government to grant a patent Congress has said that you must describe your invention so that others will be able to benefit from it, learn from it and advance it moving forward. The only way to do this is by describing your invention with great care and detail.

When you file a patent application it is always necessary to file an application that completely and clearly describes the invention so that others would be able to understand the invention. For many, particularly new inventors, business executives and newbie patent attorneys or agents, it is difficult to understand the so-called description requirement to patentability. It seems easy enough to comprehend as a general matter, but it is overly simplistic to merely say that a patent application must describe the invention. Those who fall down with respect to this adequate description requirement do so because they do not have a full conceptualization of what it is that they have as a protectable invention.

Notice my choice of words carefully. I am not saying that inventors do not know what they have invented; they most assuredly do, at least if there is a patentable invention. What inventors, and newbie patent attorneys and agents fail to appreciate, however, is that far more than what has been invented is patentable. Still further, even those who do appreciate the full glory of what can be protected frequently fail in providing what an experience patent attorney would call an adequate description because they only describe the invention in language that is one inch deep and a mile wide. The mile wide part is good, but you want to also drill down far more than one inch to teach the various nuances of at least certain key aspects of the invention.


It is critical to drill down for many reasons, but from a practical standpoint let’s remember that you will file your application anywhere from about 30 months to 48 months before you are likely to receive a first office action from a patent examiner. By the time you do get consideration from a patent examiner you are going to definitely want to have all kinds of detail in the application so that you have nuances to layer on to the broad claims you filed so as to be able to convince the patent examiner that you have patentable subject matter. Without nuances in the specification you will be out of luck if and when the patent examiner finds good prior art to use against you.

The crux of the adequate description requirement is the enablement requirement, which can be found in the first paragraph of ‘ 112, which states:

The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.

Also contained in the above paragraph is the best mode requirement.  With passage of the America Invents Act the best mode requirement has largely, although not completely, gutted.  It is still a requirement under 35 U.S.C. 112, but there is no teeth to the requirement because the failure to disclose the best mode cannot invalidate a patent claim.  So at best the best mode requirement is now a toothless tiger.  Many anticipate that eventually Congress will get around to deleting best mode from Section 112 altogether.

The enablement requirement, which does remain in full force and effect, requires the applicant to describe his or her invention in a manner that would allow others in the industry to make and use the invention.  The enablement requirement looks to the objective knowledge of one of ordinary skill in the art and works to require the inventor to describe the invention, and all aspects and variations thereof, with the greatest amount of detail that can be provided. Essentially, enablement looks to placing the subject matter of the claims generally in the possession of the public.

One of the challenges that a drafter faces when trying to satisfy the enablement requirement is with respect to describing things that can and will vary depending on the circumstances.  What you want to do is follow up by explaining the various permutations to help the reader more readily understand what facts, choices or circumstances will have impact.

For example, compare these five statements (which are used for illustrative purposes, not as medical advice):

(1) “Adults can take 2 capsules of X to relieve pain every 6 hours.”

(2) “Adults can take 2 capsules of X to relieve pain every 6 hours, but no more than 8 capsules in any 24 hour period.”

(3) “Adults should ordinarily take 2 capsules of X to relieve pain no more than every 6 hours, with a maximum number of capsules taken being 8 in any 24 hour period. These recommendations may vary depending upon the situation.”

(4) “Adults should ordinarily take 2 capsules of X to relieve pain no more than every 6 hours, with a maximum number of capsules taken being 8 in any 24 hour period. These recommendations may vary depending upon the age, weight and height of the person taking the capsules.”

(5) “Adults should ordinarily take 2 capsules of X to relieve pain no more than every 6 hours, with a maximum number of capsules taken being 8 in any 24 hour period. These recommendations may vary depending upon the age, weight and height of the person taking the capsules. If you are going to take more than 8 capsules in any 24 hour period you should first consult your physician.”

Notice how each statement provides more and more information, with statement 4 including both the general, as well as at least some information to guide the reader in understanding when what is preferable may be deviated from. Statement 5 even builds upon that to give the reader an action item with respect to deviation from the standard. What you want to aim for is something far more like (4) or (5) than like (1).

In the above example the invention relates to a method, but the need to disclose variations depending on circumstances is not unique to method inventions.  A patent application needs to define the actual physical characteristics of the components of the invention.  You can do this by describe a generic version of the invention and then ever more detailed alternative embodiments, some of which may include certain piece, parts or features some, but not all, of the time.

When dealing with a tangible invention, patent applications need to define the structure of the overall invention, but also the structure of the components.  It is important to describe everything so that the reader will be able to picture the invention in their mind.  This may seem a silly comment for some inventors and newbie patent attorneys or agents because they frequently will think certain aspects of their invention are inherent in what they have already said, but remember, a patent application needs to explain the invention to someone who is not already familiar with the invention.

The best way to explain an invention to someone who is not already familiar with the invention is to explain it like so many of us used to do when we were kids doing a show and tell at school.  A child doing show and tell explains everything, no matter how obvious or inherent.  Kids do this when they describe things because they have no idea what the person listening knows, and to them it is new and interesting so they explain everything with tremendous detail (whether you want to hear it or not).  That is exactly what should be done in a patent application.  Explain the invention with so much detail that you will bore the knowledgeable reader to death.  That won’t make for entertaining reading, but it sure will make for a wonderful disclosure that will support a great many claims and can become the foundation of a patent portfolio if the invention ultimately becomes lucrative enough to warrant it.

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One comment so far.

  • [Avatar for John Roethel]
    John Roethel
    January 31, 2012 08:23 am

    I would also suggest that a patent application is a technical writing, not a creative writing. If an element is a spacer, always call it a spacer. Not a spacer one time, then a separator then next time and then a divider the next time.