How likely are you to obtain a patent for your invention? If you made and sold it right now, would you be infringing someone else’s patent? Researching the patent databases will help you answer these questions and give you a good idea about whether your innovation is already described or claimed by others. Certain patents and patent applications that you uncover, commonly referred to as “prior art,” will be more relevant than others. Note, though, prior art also includes publications and unpatented inventions. Moreover, there is a difference in the effect of discovering a description of your invention in some prior art, but failing to find it covered by any claim in any patent. Before we look further at that, let’s explore a way to research the prior art, for this example, in the US Patent & Trademark Office (USPTO) database. Conveniently, the USPTO search page allows you to conduct a simple search using two keywords at a time. My choice is to employ the keywords for a search of the patent abstracts. In using this method, it is essential to come up with all the words you possibly can. The reason is, if you inadvertently omit a relevant keyword, you could conceivably miss a critical patent—one that might otherwise cause you to abandon your idea or, at least, alter your course. Here is an example of a reasonable breadth of keywords for a patent search where the invention is a novel device for detecting the degree of strabismus in young patients. The first term, “diagnosis,” is paired repeatedly with each succeeding word. For instance, “diagnosis + strabismus,” “diagnosis + refraction,” etc. After pairing the entire list with “diagnosis,” the word “diagnose” is then used in the same way: “diagnose + strabismus,” “diagnose + refraction,” etc.  “Diagnosis” + (also “diagnose”) Strabismus Refraction (Mis)alignment Isotropia Exotropia Hypotropia Hypertropia Eye (and eye +misalignment) Acuity Vision Prism Occlusion Anisometropia Each search with a pair of keywords can turn up a range of patents, from none to hundreds. Based on what your own search uncovers, begin reading each abstract to see if it is relevant to your invention. Does it come anywhere close to describing your idea? If not, put it aside for now. If it does, let’s next turn our attention to that patent’s claims. Are you potentially infringing? Is there room to obtain your patent without infringing? Certainly, issues of patent infringement should be determined by your patent counsel. However, if you are conducting your own prior art search, as I suggest you do, do you ask your attorney about each patent you turn up? My recommendation is that you, as the inventor, should try to determine which patents you should run by your attorney and which could be filed away for later use as a cited reference in your own patent application. The following is a guideline for assessing infringement. Below, for our example, is a claim from an existing patent. Notice carefully how the claim contains a main subject or topic—a data acquisition system for use in sporting events—with multiple related sub-topics, e.g., the data acquisition system for use in sporting events with at least one inertial sensor. Let’s call each topic an element. Looking through this claim we can see that multiple elements are described: A data acquisition system for use in sporting events which incorporates: at least one inertial sensor measuring angular acceleration in at least one dimension at least one accelerometer to derive acceleration and velocity data in 3 dimensions a microcontroller with a clock to measure the angular acceleration and accelerometer data a power supply optional communication means for transmission of angular acceleration and accelerometer data from the microcontroller to a computer device said computer device and/or said micro controller being programmed to use the angular acceleration and accelerometer data to provide accurate output of parameters such as velocity, acceleration, changes of direction and distance traveled. So, here is what you should know about infringement. In order for literal infringement to occur, each and every element in at least one claim of a patent must be infringed. If your invention omits one or more elements in another’s patent, it is arguable that no infringement occurs. A challenge in understanding infringement, though, is properly teasing apart the claim into its elements. Here is how I might break the above claim down into its elements: A data acquisition system for use in sporting events which incorporates at least one inertial sensor measuring angular acceleration in at least one dimension at least one accelerometer to derive acceleration and velocity data in 3 dimensions a microcontroller with a clock to measure the angular acceleration and accelerometer data a power supply optional communication means for transmission of angular acceleration and accelerometer data from the microcontroller to a computer device said computer device and/or said micro controller being programmed to use the angular acceleration and accelerometer data to provide accurate output of parameters such as velocity, acceleration, changes of direction and distance traveled. Notice that my breakdown of the claim into its elements results in a description that looks very different from the example claim. So, think carefully about what I am about say. What if the first two elements describe our device, but the third, measuring angular acceleration, is something our device absolutely does not do? If we employ a another method that is novel and non-obvious, say, for example, a sensor that detects electromagnetic field strength, chances are, we would not infringe this claim. The fewer elements we infringe, generally speaking, the more we distance ourselves from infringement issues. If, in the foregoing example, you found only one difference between your device and the referenced patent, it might be a good idea to have your attorney look at it. Before we breathe a sigh of relief and file this patent away because no claims appear to be infringed, there is one more thing to check. Do any of the patents contain examples or details in the brief or detailed description that explain your innovation—yet are not mentioned in that patent’s claims? If you find your idea described in a patent, but not claimed in any patent, you may have a patentability issue. In other words, if this description is not covered by that patent’s claims (or by the claims in any patent), then the described idea is most likely “public domain.” If an idea is in the public domain, it means that it cannot be patented by anyone. Instead, anybody may freely make, sell and use it. If you were seeking the advantages afforded by patent protection for your innovation, an issue of public domain would not be good news. Normally, we would expect something covered by the claims to also appear in the patent’s brief or detailed description. It usually is, but not always. This example of public domain is similar to discovering that your innovation has been described (more than a year ago) in a journal article or other publication. If that occurs, and no patent claims have been filed on it, the idea is public domain and may be used freely by anybody. If you come across such a description published less than a year ago, confer with your patent attorney on its impact. Think you got it? If your innovation contains or performs each and every element in any claim of another patent, you may have infringement issues. If you find your innovation described in a patent or in any publication, and it is not covered by any claims in any patent, then you may have a patentability issue. If you are lucky, and your idea appears to neither infringe any patents, nor face a public domain issue, then, from a patent law perspective, your own patentability is probably looking pretty good. However, you know from our prior discussions that it is possible to obtain a patent that does not confer any meaningful competitive advantage in the marketplace. And, if you cannot sustain a competitive advantage, neither customer nor investor may be interested in your innovation. Next up I'll walk through how to unearth your competitive advantage (if any!) and meaningfully tie it to your patent application.