Identifying Patent Invalidity Grounds: 8 Prior Art Pitfalls

A patent invalidation search is a prior art/novelty search performed on a granted patent in order to invalidate the patent’s claims. It is done on the basis of novelty, obviousness, and/or inventive step. These searches are carried out in order to identify relevant patent and non-patent literature that corresponds to the claims of the subject patent and is frequently overlooked by the examiner during examination. 

When to Conduct a Patent Invalidation Search? 

Patent invalidation searches are carried out in the following scenarios: 

Remedy for Infringement 

When a patent owner (plaintiff) files an infringement case in a court of law against an alleged infringer (defendant) for unlicensed/unauthorized/illegal use of his patented invention, the defendant conducts a patent invalidation search in order to render the claims invalid. There will be no infringement lawsuit if the patent grant is declared invalid. 

Prior to filing a lawsuit for infringement 

A patent holder may request a validity search to confirm the validity of the claims prior to suing an alleged infringer. If no satisfactory prior art is found during the search, the subject patent’s claims are assumed to be useful, novel, and non-obvious. This ensures that the patent holder can file a lawsuit against potential infringers. 

Patent portfolio licensing 

A validity search can be carried out on behalf of a potential licensor who is interested in licensing an innovation. To manufacture or sell the products disclosed by the claimed invention, the interested party (licensor) would require a license from the patent holder. As a result, before investing a significant amount of money and time in the licensing process, the potential licensor requests a validity search. This enables them to assess the portfolio strength of the patent(s) of the inventor/assignee they intend to license. 

Mergers & Acquisitions 

When a company1 wishes to acquire a company2 in order to acquire the IP portfolio owned by company2, the company1 requests a patent valuation and validity search on the patent portfolio in order to determine the strength of the company2’s patents. A patent with valid claims increases the patent’s value. 

Identifying Patent Invalidity Grounds 

During a patent invalidation search, the following grounds must be identified: 

• The presence of published prior art or public utility or sale of the patented product, technology, process, or service prior to the subject patent’s earliest priority date. This indicates that the innovation was not novel in the first place and was granted incorrectly 
• Insufficient or missing patent specification that does not fully support the claimed matter 
• Rejections (for example, 35 U.S. Code 101, 102, 103 rejections) made by the examiner during examination of the subject patent and subject to review by the Patent Trial and Appeal Board (PTAB) 
• Objections proceedings by 3rd parties who are interested in re-examination during the patent’s pre-grant or post-grant review 
• Inter partes review (IPR) is a procedure for contesting the claims of an issued patent in which the interested party is fully involved in the proceedings 

Common Pitfalls of Prior Art 

1. Not comprehending the novelty correctly 

When conducting a patent invalidation search, it is critical to correctly understand the patent’s novelty and the way the present invention differs from the background, which changes have been introduced, and what the effects of the changes are. Incorrect understanding of novelty leads to incorrect analysis and shortlisting of references that may teach away from the innovation. A thorough file history analysis and careful reading of arguments between the examiner and the applicant are required for a correct understanding of the novelty. Furthermore, the examiner explains why claims were allowed. 

Patent file histories for various countries are publicly available and can be accessed via the respective registry sites of those countries. For example, for a US patent, go to the USPTO patent center, for an EP patent, go to the EPO register, and so on. 

2. Choosing a search cut-off date 

In most patent invalidation search cases, the priority date of the subject patent is used as the search cut-off date in the first instance. However, this is an incorrect practice that may cause problems if relevant prior arts are neglected due to an incorrect cut-off date. 

In most cases, the client requests the earliest priority date or earliest filing date as the cut-off date. However, this is not true when the subject patent is a continuation-in-part application of a parent application. There is a good chance that a new subject matter has been incorporated to the specification and claimed in this case. As a result, its filing date becomes the search cut-off date for this newly claimed matter, rather than the earliest priority date. 

Furthermore, different jurisdictions have distinct laws regarding the date criteria for declaring a patent invalid. 

3. Incorrect interpretation of a claim 

The searcher should be aware of the claim constraints and requirements before beginning the patent invalidation search. For a proper understanding of the various possibilities that different embodiments specify, it is critical to read the claim in light of the specifications. Incorrect prior art searches are frequently the result of a failure to comprehend the claim language. 

4. Concentrating solely on patent literature 

Sometimes a searcher is only interested in finding prior art in patent databases. Thus, they pay little to no attention to non-patent literature that could be very useful otherwise. This may result in the omission of relevant prior art because: 

• The searcher may have overlooked an NPL such as a journal, research papers, dissertations, books, blogs, and so on.
• The searcher may have overlooked relevant products or product manuals that were available prior to the search cut-off date.
• The searcher ignored standard searches involving technology standards from various SSOs, including IEEE, 3GPP, ETSI, ANSI, and others. 

This is because patent databases such as Questel Orbit, Patsnap, XLSCOUT, and others are very well maintained, and creating a structured query on a patent database is easier than on a non-patent database. Furthermore, patent databases offer high-quality filters such as country code, date criteria, classification-based search, assignee search, and so on. Furthermore, many publications are not accessible via the internet. To identify such prior arts, printed literature should be examined by visiting physical libraries.

To avoid this problem, XLSCOUT has come up with an AI and NLP based search tool. This tool provides the user with a list of potential non-patent prior arts.

5. Using incorrect keyword variations 

A patent or patent application specification will typically use only a few variations of a keyword. For example, one inventor may use the term “camera” to refer to a device capable of capturing multimedia. Whereas another inventor may refer to a similar device using the terms “camcorder, ICD, videocam” and so on. As another example, one inventor refers to protrusions of a semiconductor device as “pillars.” Whereas another refers to them as “fingers, pillars, protrusions, or simply raised portions.”

Searchers frequently formulate search queries using only the keywords used in the subject patent, ignoring other synonyms for the word. To ensure that no prior art is overlooked, all relevant variations of a word must be searched for. The searcher can use a dictionary, thesaurus, or XLSCOUT proprietary corpus to help with this problem. 

6. Only looking for 102(b) Prior Arts! 

According to US Patent Law 102(b), an art is considered valid prior art if it was published one year prior to the subject patent’s earliest filing date. This type of prior art is considered the strongest in a court of law if it discloses all of the elements of the subject patent’s claimed invention. 

However, due to a one-year gap, such an art can be difficult to identify at times. As a result, a searcher seeking 102(b) prior art may overlook better arts that fall under 102(a) or 102(c) (e). Furthermore, the searcher should keep in mind that two or more references can be merged together. Further, they can be used to demonstrate the illegitimacy of a claimed matter under obviousness (103).

The searcher should shortlist a variety of prior art references that cover all aspects of the claim, either alone or in conjunction with other references. 

7. Not utilizing appropriate search platforms 

Invalidating a patent necessitates extensive research not only on free databases but also on paid databases. These paid databases contain a large number of indexed patents from around the world that are otherwise not freely available. Furthermore, these databases provide high-level English translation for foreign non-English references. Moreover, they also provide a list of patents that have recently been published and are not available on free databases. These databases include XLSCOUT, Questel Orbit, PatSnap, LexisNexis TotalPatent, and others. 

8. Relying Only on Prior Art Patent Claims 

In addition to the claims of the prior art, the entire specification of the prior art, including the abstract, summary, detailed description, and drawings, must be considered when mapping a prior art patent reference to the claims of the subject patent. Using only claims for mapping purposes is a very bad idea. The text used could be found anywhere in the prior art that has been published. 

Our Methodology 

Invalidator+ by XLSCOUT is artificial intelligence (AI) enabled app that allows users to quickly conduct a first-pass patent invalidation search by focusing on specific competitors’ patent claims. Users can supervise the machine by selecting claims of interest and technical variations/keywords after entering the subject patent number. The Invalidator+ tool provides a list of relevant prior art results along with an automated invalidation search report.

This AI-powered patent invalidation search tool combines intelligent patent parameters such as classification, citations, assignees, and so on with Patent Para-BERT technology to generate a quick patent invalidation search that uncovers results based on contextual and expert parameters. Invalidator+ also utilizes Reinforcement to provide accurate prior art or invalidation analysis.

Benefits of using XLSCOUT’s Invalidator+   

• Easy-to-use interface
• Quick first pass patent invalidation search by entering the patent number
• Fully automated first invalidation search report
• Analysis concentrating on specific claims
• High Accuracy with Reinforcement Learning