Patent Drafting: Language Difficulties, Open Mouth Insert Foot

Lately I have been this “educational” mindset more than is usual. Not only am I gearing up for the run of summer Patent Bar Review Courses, which begin next week in New York City, but at the beginning of June I will be teaching a Patent Prosecution course for a week at the John Marshall Law School in Chicago, Illinois. What better topic to revisit than the importance of using the right language when describing an invention and dealing with an examiner. Patent attorneys darn near need to be magicians when it comes to language, which is the primary tool of our craft. Picking the right word and the right way to say things is critical. Even more critical, perhaps, is not saying the wrong thing, or worse yet saying something that is clear but not what you intended.

When dealing with the topic of picking and using the right language to describe an invention in a patent application it is worth observing that having a dictionary and thesaurus at the ready is a pre-requisite to being a good drafts-person. If you are not consulting a dictionary and thesaurus you are doing yourself, or your client, a tremendous disservice. But picking the right word is but one of the problems, and probably the easiest to deal with if you train yourself not to assume you have a Shakespearean grasp of the English language and force yourself to consult that dictionary and thesaurus. So today I thought I would focus on a couple big ticket matters that are easy to overlook, at least when patent novices are doing the drafting.

First, no article on precise language would be complete without the nearly obligatory reference to the 2004 case of Chef America v. Lamb-Weston. In this case the Federal Circuit issued a decision that drives home how important it is to choose your words in order to make sure your words are exactly what you mean to say. In this instantly famous case the Federal Circuit had to interpret the meaning of the phrase “heating the resulting batter-coated dough to a temperature in the range of about 400° F. to 850° F.” What should have been said was “heat the oven to a temperature in the range of about 400° F. to 850° F.” Because what was said literally required the internal temperature of the dough to reach between 400° F. to 850° F., the patent owner had a useless patent. If you heated the dough to between 400° F. to 850° F. the resulting output would approximate a charcol briquette, but that wasn’t the Federal Circuit’s problem. Because the words chosen had a specific meaning that was what was protected. Lesson one: no court or judge will save you from poor drafting; what you say literally is what you get.


Another language based mistake I see inventors make a lot probably has more to do with not understanding the role of a patent than inappropriate use of language. For example, inventors frequently seem to believe that a patent application is supposed to be a historical record of how they arrived at their invention, with the various twists and turns, false starts and mistakes all explained. This is not something a patent attorney would do, choosing rather to focus on a positive description of what the invention is as it has been invented and could be manifested in a variety of alternatives. For more on alternatives see The Key to Drafting Excellent Patents — Alternatives.  As bad as this may be, what really is problematic is when those who are treating the patent as a historical invention record point out what they don’t yet fully understand or appreciate and what else needs more work to complete.  Huge mistake.

I like to refer to the admission that an invention is incomplete as “experimental language.”  This type of information and notes to yourself in an invention notebook is fine.  You need to keep your thoughts collected and document what you do that works, but more importantly what you have done that doesn’t work.  You will never be able to remember everything you have tried, what worked very well, what worked not so well, so having copious notes is definitely positive, you just don’t want that in your patent application.

What I refer to as “experimental language” either explicitly or implicitly suggests that further experimentation is or will be necessary in order to: (1) realize or perfect the invention; or (2) realize or perfect an intermediate or component.   Resist the temptation to have your patent application read like a diary of thoughts and/or personal observations regarding future research and goals.  This type of language is usually not found in a patent application because it suggests that your invention is not yet completed, which could be used as an admission that the invention is not enabled and/or that you have not satisfied the written description requirement.

In a nutshell, the so-called enablement requirement requires that each invention work and be described in enough detail so that someone of skill in the area can make and use the invention.  The invention must be enabled as of the date the application is filed, therefore, any language that explicitly or implicitly hints that the invention may not be complete is not appropriate.  Similarly, the written description requirement must also be satisfied at the time of filing, so anything that suggests an incomplete written description makes the patent application fatally flawed.  Unlike enablement, the written description requirement is there to make sure a complete invention has been articulated and the inventor is in possession of everything described, meaning the inventor understands the full glory of the invention.

In patent history Samuel Morse (of Morse Code fame) ran into a written description problem when he tried to claim electromagnetism for whatever purpose later developed.  Truthfully Morse had one particular use of electromagnetism, not all possible uses that may later be developed, so he was given a patent on the implementations he described with certitude.  If you are not in full possession of what you are articulating then you are hypothesizing, theorizing or just flat out guessing.  You cannot get a patent on a hypothesis, theory, guess or incomplete invention.  So be careful how you articulate what you have and what you don’t have.  Just positively describe what you do have and keep those notes about what needs to be done for version next to yourself.

You can always follow up with another patent that improves your own invention, which you should if your base invention is commercially viable.  After all, if you don’t seek to improve your own invention others will and if they obtain a patent on an improvement they can prevent you from making, using or selling that improved version, thereby blocking you from future improvements of your own invention.  Sure, if you have the base patent you can prevent them from making, using and selling, but do you really want to have your own invention blocked in?  Probably not.

Don’t think you need to include every speculative thing in a patent application.  Invention is a process.  It is akin to being down 5 runs in the bottom of the 9th inning.  If you are the first batter of the inning a homerun does you no good, and you run a higher risk of striking out swinging for the fences.  You need base runners, so you little by little try and chip away at the lead.  With an invention you want to solidly describe whatever you can to the best extent possible and then continue to improve and refine your invention over time, which can and probably should result in additional patent applications to cover those improvements.

So how do you prevent yourself from saying too much about your invention, minimizing what you have done with respect to your invention and otherwise putting your foot in your mouth?  Try and consider how someone who is unfamiliar with your invention would read what you write.  If the reader would be left with the understanding that there is more left to be done in order to realize or perfect the invention you are describing you are treading on thin ice.  I strongly suggest that you stick with describing what it is that you have presently invented and leave off any discussion of future research or future projects.  If you do not yet have certain variations of the invention completed then hold off on describing those, at least for the time being.  As you do perfect and complete other variations a new patent application can, and probably should, be filed.


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2 comments so far.

  • [Avatar for patent enforcement]
    patent enforcement
    May 9, 2011 02:27 pm

    The more you learn about patent law, the more you have to appreciate the importance of quality patent drafting. Clever patent drafting can render a questionable “invention” patent-eligible, while careless drafting can completely deprive a brilliant innovation of IP protection. It follows from this that EVERY inventor who thinks his or her invention is worth patenting should consult a patent prosecution attorney, instead of trying to “go it alone.” If it is worth patenting, then it is worth patenting correctly.

  • [Avatar for John Spevacek]
    John Spevacek
    May 6, 2011 10:04 am

    “… inventors frequently seem to believe that a patent application is supposed to be a historical record of how they arrived at their invention, with the various twists and turns, false starts and mistakes all explained. This is not something a patent attorney would do,…”

    If you ever need help explaining this to a client, a similar example is what appears in research publications (scientific journals). The whole article is “whitewashed” so that it appears as if the experimenters went into the lab with a beautifully prepared hypothesis, they ran the experiments, saw that the got the desired results, and so they published the paper (which was accepted after peer review without any changes, additional experiments…) You never get the historical perspective of how they originally thought X, but couldn’t get that to work so they tried Y and Z and … and then the equipment broke and gave them faulty readings and then…