I Can’t Find Prior Art for My Invention

I am frequently told by inventors that they have done a patent search and cannot find anything that remotely resembles what they have come up with. While there are many reasons for not finding prior art, just because you do not find prior art does not mean that there is no prior art to be found. In fact, it would be extremely rare (if not completely impossible) for there to be an invention that does not have any relevant prior art.  Said another way, unless you have invented something on the level of an Einstein-type invention there is prior art, you just haven’t found it.

Prior art is probably best understood as information that can be used by the patent examiner to reject claims in a patent application. This information is most commonly prior publications, such as technical articles, issued patents or published patent applications. It is also possible for prior art to consist of actions, such as a sale or public use prior to a patent application being file. But for the sake of this article let’s assume that the prior art we are talking about are issued patents and published patent applications.

It is absolutely critical to understand that a reference, such as an issued patent or published patent application, does not need to be identical to an invention in order for the reference to qualify as prior art. A reference can be used as prior art for whatever the reference explains. For example, if you design 5-wheel transportation device you are going to have to distinguish all other wheeled transportation devices, regardless of whether they are identical. So if a patent examiner finds a 4-wheeled transportation device that will be used against you as prior art. It will be up to you to explain why your 5-wheel device is not obvious in light of the 4-wheel device. The critical question will be this: Why wouldn’t it have simply been obvious to simply add another wheel?

In a nutshell, the key to understanding prior art is to understand that anything similar or in any way related to what you have created is going to be prior art.


There are primarily two questions that must be answered. First, is the invention patent eligible? Second, is the invention new (i.e., novel) compared with the prior art? Third, is the invention non-­obvious in light of the prior art? We engage in this three-­fold inquiry to determine what, if anything, can reasonably be expected to be obtained in terms of claim scope.

The question about whether or not there is any single reference that is identical to your invention is a threshold inquiry. Exact identity is a matter under 35 U.S.C. 102, which is the part of the patent laws that relates to what is called “novelty.” If a prior art reference is found that discloses all the elements of the invention, the inquiry ends because no patent can be obtained. If no single prior art reference identically describes each and every aspect of your invention this novelty hurdle has been cleared.

Assuming proper search techniques are used and everything that can be found is located, inventors who say there is no prior art universally are saying that there is nothing identical. But there is a critical consideration beyond the question of exact identity. You must focus on what distinguishes your invention over the totality of the prior art. This is required because when a patent examiner deals with issues of obviousness (i.e., 35 U.S.C. 103) they will look at a variety of references and pull one element of the invention from one reference, and another element of the invention from another reference, ultimately seeing if they can find all the pieces, parts and functionality of your invention in the prior art. The patent examiner will then attempt to combine the various elements and functionalities found to see if the collection together  discloses your invention. The true inquiry for the patent examiner is to determine whether the combination of the pieces, parts and functionality found within the prior art would be considered to be within the knowledge base of one of skill in the art such that your invention is merely a trivial rearrangement of what is already known to exist. If it is then your invention is obvious.


The elusive nature of what is an obvious invention is due to the fact that what is obvious has been elusive to the Supreme Court of the United States, who thinks that it is a matter of “common sense.”  The “common sense” test urged by the Supreme Court, however, ignores that fact that after one learns of something it is always common sense.  In essence, the Supreme Court test is overly simplistic and unrealistic.  Thankfully the Patent Office and the Courts have chosen to largely ignore the Supreme Court test as literally written, but that only adds to the confusion for inventors trying to make sense of what it means to be obvious.

It is indeed difficult in some situations for those familiar with patent law to determine what is obvious in light of the rapidly evolving law in this area.  Everyone knows about crazy inventions that have been patented, and even after the US Supreme Court expanded the definition of what is obvious to include those things that are considered “common sense” the Patent Office continues to issue patents on “inventions” that certainly seem to be within the common sense of virtually anyone. All of this can make it quite difficult to determine whether an invention will be perceived to be obvious, which is the real, substantial hurdle any inventor faces on the road to obtaining a patent.

It is important to understand that in order to obtain a patent it is not enough that an invention be new and/or different when compared to what already exists, but rather it must also be a non-trivial combination, which means that one of skill in the art would not have thought to make the invention prior to seeing it described. In other words, it cannot be considered to be a common sense or trivial variation of what has come before. There must be some kind of unanticipated innovative step. Something that would make those in the field of endeavor say “ah, interesting.”

If you are tempted to think or believe that there is no prior art for your invention think again! In all but the most revolutionary of inventions there will be components and structures that are similar to the components and structures of what has been newly created. Similarly, for practically every invention there already exists one or more solutions to accomplish the same or similar task. All of those devices and methods that purport to accomplish the same or similar task are going to be prior art, even if they are clearly inferior.

What you need to do is focus on what is unique and ask whether that point of novelty is enough to warrant a patent.  Of course, in order to reach this determination you need to know what is out there that will be used to measure up to your invention.  This absolutely requires that inventors get out of their head that their invention is so revolutionary that no one else could have ever possibly come up with the invention.  When a complete, professional grade search is done vast quantities of prior art will be found, and it becomes clear that every generation invents, and re-invents, the same or similar things.


So how is it possible that an inventor who searches cannot find prior art?  This is typically a result of failure to adequately describe the invention and then searching only limited characterizations of their invention.  For example, most inventors will look at what they have invented and then do a word search to see what else is out there.  Frequently nothing will be found, not because there is nothing that could be found, but because the description searched is unnecessarily limiting.  When a patent attorney or professional searcher engages in a patent search much effort is directed toward figuring out how others have described a particular innovation, particular features and characteristics of an invention.

A thesaurus is your best friend, because while you might describe it as a “bubble mailer” others might describe it as a “padded envelope.”  So you must endeavor to figure out all the various possible ways to describe your invention and the constituent parts.  In almost every case when you search a variety of characterizations you will eventually stumble across the characterizations that most closely matches what others have previously relied upon.  After all, there is no point in reinventing the wheel, so if those that have come before you refer to something in a certain way then you will refer to it in the same or similar way.

The moral of the story is this: there is ALWAYS prior art for your invention.  If you search and come up with nothing that is because the search has been inadequate, not because there is nothing that can be found.  If you doubt this ask yourself this: with well over 8.6 million issued utility patents issued in the United States is it likely that no aspect of your invention has ever been conceived?

Even though inventors are not likely going to find all the prior art, or even the best prior art that can be found, I do strongly recommend that inventors start by doing their own searches. If you can find something that is too close for comfort then why bother paying a professional to do a search? So definitely do a patent search yourself, and also make sure you do a product search on Google as well. Increasingly I am seeing inventors who can’t find something that is patented but if you do a simple Internet search you find their invention right there for sale.

To learn how to conduct your own patent search see Patent Searching 101 and Patent Searching 102.


Warning & Disclaimer: The pages, articles and comments on IPWatchdog.com 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 IPWatchdog.com.

Join the Discussion

12 comments so far.

  • [Avatar for Mark Nowotarski]
    Mark Nowotarski
    December 15, 2013 05:39 pm

    Speaking of prior art, there is a great discussion going on right now on patenting an improvement to a patented product in the comments section of this YouTube video. http://bit.ly/1bILJgO Yes, you can patent the improvement, but you still need a license to the original patent. Thomas Edison had to do this with the light bulb.

  • [Avatar for patent leather]
    patent leather
    December 15, 2013 02:06 pm

    Mark, I agree with you in general. But I was thinking of 10.85(a)(2), “A practitioner shall not… Knowingly advance a claim or defense that is unwarranted under existing law.” If an attorney is 99% sure he has seen an invention before, it isn’t clear to me if ethically he can still file that application or not. When dealing with unsophisticated, solo inventors, if the attorney/agent is not 100% comfortable with the representation he probably shouldn’t do it. But absent unusual circumstances (like these), I agree with what you wrote and the majority of the apps I write are not searched.

  • [Avatar for Mark Nowotarski]
    Mark Nowotarski
    December 15, 2013 01:34 pm


    Well I certainly agree we have a duty if we have knowledge.
    I also agree that we have a duty beyond the client.

    I’m not quite sure what you mean, however, by “turning a blind eye”. Can you elaborate?

  • [Avatar for Anon]
    December 15, 2013 11:12 am


    Correct – but only to a point. We have a duty if we have knowledge, and we have a duty beyond the client as to what we present to the Office in an official capacity. Turning a blind eye because a client said so does not cut it in my book.

  • [Avatar for Mark Nowotarski]
    Mark Nowotarski
    December 15, 2013 10:03 am

    Patent leather,

    There are a couple of issues here. One of my guiding principles is only do what the client has approved. So if the client has been advised that a prior art search is appropriate, but the client says “No, I don’t want one done”, then I think it’s best to refrain and rely on the examiner’s search. It’s tough to hold back, but as practitioners, we may not be aware of all of the strategic issues that an applicant may have.

  • [Avatar for Anon]
    December 15, 2013 08:24 am

    patent leather,

    Very similar occurrence for me as well. Mine turned out better though. My client (still a major client, albeit not my personal client) was likewise initially unhappy with the thought that they had ‘lost’ protection. Fortunately, the client was willing to listen as I explained that not only did they NOT lose protection (you cannot have protection that you did not have in the first place), but that the client saved not only the prosecution costs, but any possible enforcement costs – as surely the reference would have been located in one process or the other.

    (by the way, I believe that the client went out and purchased the patent, obtaining the protection they wanted)

  • [Avatar for ip guy]
    ip guy
    December 15, 2013 07:51 am

    Inventors who lack an understating of patent law also focus on searching prior art for a concrete 102 reference, not realizing that references can be combined.

  • [Avatar for patent leather]
    patent leather
    December 14, 2013 11:35 pm

    One time an independent inventor hired me to prepare and file a utility application for him on a very simple invention. I kept recommending we do a search but he insisted that he already did his own search and there was nothing like it out there and told me not to do a search. I felt ethically conflicted about taking thousands of dollars from someone to file an application on something I was almost certain was done before. So I looked on the USPTO site myself and in about a minute I found a clear 102 reference. I told the inventor and he was pissed at me and acted like I did something wrong (I guess I rained on his parade). I apologized and didn’t charge him anything.

    Would anyone here have handled that situation differently?

  • [Avatar for Gene Quinn]
    Gene Quinn
    December 14, 2013 11:35 am


    Looking in the wrong areas is a big problem, but I also see a lot of problem with failure to understand what is obvious. “But mine is yellow, which makes it very different and non-obvious” is the type of argument I hear every once in a while from an inventor who just refuses to let go. They typically wind up believing I don’t understand the invention and I’m not ver knowledgeable. In one case over the past couple years I told someone “no go” and they went out and found someone to file. They paid a lot of money for a complex application, paid to accelerate it, didn’t get anything. Paid to accelerate the RCE and still didn’t get anything. The references used by the examiner were exactly the ones we found in our search. I stumbled across this while doing a different search. Sometimes you just can’t help people who want to believe.


  • [Avatar for Gene Quinn]
    Gene Quinn
    December 14, 2013 11:32 am


    I couldn’t agree with you more. Whenever we do a search we are looking to find what has been described, which frequently happens. The real enlightening— “a ha” moment doesn’t come until we start talking with the inventor about what is unique and what is different in the context of what appears to be very close prior art based on the way the invention was originally articulated.

    I also tell inventors that perhaps the most detailed patent application we have filed was after a “no go” opinion. The client kept working on the invention and we kept advising. What really started out as something general and not new became something quite detailed and very exciting.

    Unfortunately, not all of those who do searches follow the model you and I use. I just saw a search the other day that I would never rely upon. Within 10 minutes I found 3 much more relevant references. I see those kinds of searches every once in a while and it is disheartening.


  • [Avatar for EG]
    December 14, 2013 10:48 am


    I’ve heard this story before too. What I tell the inventor is that they’ve likely not looked in the right areas.(almost always true).

  • [Avatar for Mark Nowotarski]
    Mark Nowotarski
    December 14, 2013 10:04 am

    Gene, Another aspect of prior art searching is that inventors (and I count myself among them) unconsciously shy away from the search terms or phrases that are most likely to reveal similar ideas to theirs. After all, who wants to have their bubble burst?

    That’s why it’s so important to have an independent third party do a search. The third party WANTS to find prior art. Close prior art helps reveal the truly inventive features of an invention. Those truly inventive features become the basis of a strong patent.