Invalidity Searches for Patent Owners

At SPSG, we understand that patent owners benefit from invalidity searches prior to asserting their patents in many ways. Patent owners may adjust their strategy based on the strength of the patents. They may also amend claims to distinguish over particularly troublesome prior art. SPSG adapts our search process to accomplish these goals. For defendants, SPSG searches for two or three references that best invalidate the claims with minimal explanation necessary to make the references read on the challenged claims. For patent owners, however, SPSG uses more creative search techniques to anticipate what prior art both the most and least sophisticated defendants may cite against the patents. The goals are to prevent patent owners from being surprised by a creative interpretation of prior art and to prevent late notice of crippling prior art.

Late notice of prior art potentially results in the patents being worthless. During the course of litigation, many defendants will conduct extensive invalidity searches on patents asserted against them. They sometimes find crushing prior art that renders the patents entirely invalid. If defendants choose to file post-grant proceedings with the Patent and Trademark Appeals Board (PTAB), patent owners’ defenses are limited since the PTAB rarely allows amendment of the claims to distinguish over the cited prior art. Consequently, late notice of such prior art is particularly devastating for patent owners since they cannot amend to distinguish over the prior art and, therefore, the patents are likely to be found invalid.

Patents owners benefit from conducting their own extensive invalidity searches prior to asserting their patents by being able to anticipate what prior art will be cited against them. An early search allows patent owners time to amend claims and prepare defenses to invalidity challenges. Additionally, since the claims have yet to be interpreted in claim construction, we are careful to search for prior art that reads on multiple constructions of the claim. As a result, we return a broader range of prior art to patent owners than we do to defendants so that they may have a complete view of the strength of their patents.

For more information, please feel free to contact our offices at 626-432-7292 or email me at

Harnessing the Power of NPL Citations for Invalidity Searching

Here at SPSG, one of our strengths is our approach, capability, and knowledge of non-patent literature (NPL). NPL is often a category of prior art that is seldom explored, and is typically under-utilized at the search level. While we implement state-of-the-art search heuristics for patent searching, we also devote substantial attention to NPL searching best practices. We are constantly collecting data on NPL sources, and testing those sources for their strengths and weaknesses.

One NPL tool that offers a unique and powerful utility is Web of Science. Web of Science, which is conventionally viewed as an academia tool, offers a unique function that allows the user to see both references that are cited by the article, and also any references that cite the article. This feature is akin to backward/forward searching in the patent landscape (i.e. seeing those references cited on the face of the patent, and any patent that cites that patent). The ability to backward/forward search NPL is incredibly powerful, much like backward/forward searching patent literature can shed substantial light onto a search, the ability to do the same with NPL can yield useful and often never-thought-of search approaches. This approach can also introduce you to other terms of art that were not considered before. Thus, the ability to citation search NPL often enhances and expands the search.

At SPSG, we take full advantage of NPL, and in particular, backward/forward searching NPL. In some cases, NPL is the best avenue for certain invalidity studies (depending on the technology, or what is already known to the PTO, etc.). Therefore, it is critical to maximize the utility of NPL, and at SPSG we have that knowledge and experience. For more information, please call our offices at 626-432-7292, or email us at

Expansion of NPL

Here at SPSG, we are constantly improving not only our search techniques / heuristics, but also the tools in our arsenal. One source of prior art frequently overlooked by other search firms is NPL (non-patent literature). Due to frequency and demand by our petrochemical / oil clients for our search services, we are proud and excited to announce our access to full-text coverage of (Society of Petroleum Engineers). Onepetro is the single best source of petrochemical white papers and NPL. While we have always covered Onepetro in our searching, we now offer full-text access as well.

We pride ourselves on our knowledge and experience, and are always aiming to have the best tools at our disposal. For more information, please contact us at, or call our offices at 626-432-7292.

Harnessing the Power of Patent Information: Foreign Design Patents and Invalidity Studies

One of the more substantial differentiating factors in US design patents vs. foreign design patents, in terms of content, is that foreign design patents can contain a wealth of written disclosure that US design patents conventionally lack. This wealth of written description may provide deeper insight into the functionality or intended use of the design features. Coupling this observation, with proper translation tools, can provide a powerful source of information that, for instance, the USPTO will rarely explore during normal prosecution. Thus, foreign design patents can prove very useful when conducting US invalidity studies.

At SPSG, part of our best practices when conducting invalidity studies, is to carefully consider relevant Locarno (international design patent classification system) classification areas. If a highly relevant Locarno classification exists, it should be searched in its entirety, with special translation tools applied to corresponding abstracts and claims. This same practice can be applied to patentability studies.

In summary, foreign design patents can provide a wealth of detailed disclosure that is often overlooked, particularly in terms of invalidity and patentability studies. Knowledge of the Locarno system, access to powerful translation tools, and specialized knowledge of pertinent technologies, can substantially increase the exhaustiveness and quality of an invalidity or patentability study.

Sherman Patent Search Group, LLC seeks to provide each client with the most exhaustive search, at the most competitive price. Questions or comments? Please call 626-432-7292, or email us @