What is Patent Invalidation/Invalidity Search?

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What is Invalidation Search/Invalidity Search?

A patent invalidity search is a prior art search performed on a granted patent to invalidate the claims of the patent (also referred to as subject patent) on grounds of novelty, obviousness and/or inventive step.  

It is also known as invalidation search or opposition search. These searches are conducted in order to identify relevant patent as well as non-patent literature that is in line with the claims of the subject patent and are generally overlooked by the examiner during examination.  

These prior arts are beneficial if they are published before or are being available to the public before the earliest filing date of the subject patent. This is in accordance with various laws that are considered for invalidation by different jurisdictions. 

Table of Contents

Types of Patent Invalidation Search 

When the search is performed to check the validity of the claims, it is called a validity or validation search. The steps of performing a validity search as well as an invalidity search are similar. The only difference lies in the fact which party is interested in getting the search done.  

To further elaborate, an invalidation search is performed for a party against whom a lawsuit is filed (defendant). The defendant tries to fight the lawsuit by killing the patent itself in question based on which, the lawsuit is filed.  

However, the validity search is performed by the patent owner/assignee themselves to check whether their portfolio is strong or what are the chances of the patent being valid enough so that it would not be invalidated in the future in case of a lawsuit being filed. 

These searches can be performed under following cases: 

When a party owning a patent (plaintiff, one who files the case), files an infringement suit against a competitor (Defendant) in a court of law for unauthorized/unlicensed/illegal usage of a protected (patented) invention, the defendant resorts to invalidity search to render the claims invalid. Once the patent grant is declared invalid, there will be no infringement suit. Thus, it is used as a remedy against infringement contention. 

A validity search may be sought by the patent holder to check validity of the claims before suing an alleged infringer. If no satisfactory prior art is identified during the search, the claims of the subject patent are assumed to be novel, non-obvious and have an inventive step. This assures the patent holder that they can allegedly file a case against potential infringers. 

Validity search can also be performed on behalf of a potential licensor interested in licensing the invention. The interested party (licensor) would need license from the patent holder to manufacture or sell the products disclosing the claimed invention. Thus, before investing a huge amount and time in the process or licensing, the potential licensor requests a validity search. This helps the licensor to determine strength of portfolio of the patent/patents of inventor/assignee they are going to license. 

When company1 is interested in acquiring company2 in order to take hold of the IP portfolio owned by company2, company1 requests a patent valuation and validity search on the patent portfolio to determine the strength of the patents of the company2. A patent that has valid claims adds more value to the patent.  

Further, the patent portfolio can also be ranked on the basis of certain parameters such as number of cited references, number of citing references, largest invention families, number of independent claims and dependent claims, litigations, reassignment, etc. The higher the rank of a patent, the higher is its value in terms of strength. 

Scope of Search 

Patent validation/invalidation searches are always performed on the claims of the subject patent and little focus is given to the subject matter and different embodiments present in the description. However, the claims are interpreted in the light of the subject matter.  

The client can get the invalidation search done on various claims decided on the basis of infringement contentions. One can get this information from a complaint letter filed in the lawsuit. Complaint letter can be accessed from various sources such as RPX, USPTO, etc.  

Search Strategy 

The invalidation search begins with first assigning a team that understands the patent invention and establishing a search cut-off date. Generally, the earliest priority date (sometimes also referred as the earliest filing date) of the patent is considered the search cut-off date.  

Any patent or non-patent literature (also known as prior art) disclosing the claimed invention or giving the idea of the invention to a person skilled in the art can be used to invalidate the patent in question or also known as subject patent. Prior art must be published before, used before, known before, or sold before this date in order to act as a valid prior art and to be used in the court of law to prove the claims invalidity. 

There are different search criteria to identify prior arts. A set of search strings are collected and applied to various databases. Search strings are formed based on different technical and non-technical keywords and related synonyms, based on international classifications such as IPC, CPC, ECLA, FI/F-terms, etc, based on the most active players in the domain and other strategies.  

To begin, various searches such as citation analysis, similar search or family analysis in other jurisdictions, and their prosecution history analysis can be performed as a first pass search strategy. 

Citation Analysis is analyzing a patent set comprising A OR B, where A is forward citations of backward citations of the subject patent and B is backward citations of forwarding citations of the subject patent. These citations A, B can be OR’ed or AND’ed depending upon the number of search results, time allocated for search, etc. Note that in this case, A and B are just used for explanatory purposes and can be used interchangeably. 

Family Analysis in other Jurisdictions and Their Prosecution History Analysis is information set comprising backward citations of the backward citations of family members of the subject patent, apart from the backward citations and their family members of the subject patent. Now this appears absurd, however it makes ideal sense.  

This is because, it’s miles possible that in a few cases, the family members of the subject patent have one or more exclusive backward citations than the subject patent itself. These backward citations which aren’t cited at the face of the subject patent, as a result can show to be beneficial to invalidate the subject patent. Therefore, it is wise to examine this information set. 

Similar search is simply a set of patents that are of similar domain or field of technology as that of the subject patent. Thus, they can prove to be useful. 

Along with patent search, one must also perform a non-patent search on various databases such as Google, IEEE Xplore, Science Direct, etc. The non-patent prior arts must be published or available to public before the search cut-off date.  

Apart from this, one can also perform a standard based search on various standard databases such as IETF, ITSE, 3GPP, etc.  

Search Databases 

There are different databases paid as well as free, where search strings can be formed and applied for performing the search. One such efficient tool is the XLSCOUT Patent Invalidator+ Tool. It is an AI and NLP-based search tool that enables you to conduct a quick invalidation search by just entering the patent number.  

Automated Invalidation combines intelligent patent parameters including classification, citations, assignees, etc. with Natural Language Processing models to generate a quick Patent Invalidation search to uncover results based on contextual and expert parameters. 

Invalidation flow

How to Perform a Patent Invalidity Search? 

Assigning a Team/Research Team 

Once your firm/organization has received a search request for an invalidity search the first step to be followed is to investigate the domain of the patent to be invalidated and all the instructions provided by the client.  

Then, based on the domain and other factors like committed submission dates, budget, and allotted hours/days for the search, a team of experts is assigned including a hierarchy from a manager to research analysts. 

Understanding the Patent 

The task for an analyst is to understand the patent and it’s claims. The claims to be searched upon may differ depending on the client requirements. It could be the broadest independent claim, all independent claims, all claims, asserted claims (claims which are asserted in an ongoing litigation case and the complaint letter including the same can be extracted from RPX insight), or only dependent claims etc.  

The process of understanding includes reading the title, abstract, summary and then reading the claims. Then moving to the description to understand the difficult/narrow parts of the claim. The major part in understanding a claim is to understand it’s novelty and the file history/file wrapper which includes all the drafts, arguments by the applicant to the rejections by the examiner and notice of allowance etc. is used for this purpose.  

The file history/file wrapper/prosecution history for US/WO patents/applications can be extracted from USPTO Public Pair or from Espacenet. Once this is done, the understanding is discussed internally with the manager/team head and can also be discussed with the client to be on the same page of understanding and requirements.  

Clients can also communicate their requirements or any specific points to be focused on while the search. Sometimes, the clients have got done the preliminary search on the subject patent internally which could result in finding a few elements of the claim.  

The clients can also share those so that the searchers can exclude the already known citations from their search scope, and can also focus their search on finding limitations that are not disclosed in the already known art. Further, the clients might be aware of some parties or assignees or players highly active in the domain and they can let the searchers know that too which will help them to particularly focus on such assignees.  

Determining Search Cut-off Date/Date for Search 

The earliest priority date or earliest filing date of the subject patent is the search cut-off date in most of the cases. However, there might be an exception if the subject patent is a CIP (Continuation-in-part) of another patent application.

In this case the analyst determines if there is any part/text of the target claim(s) corresponds to the newly added description in the CIP. If there is some part of the claim falling under the scope of the newly added description, then for that part of the claim the search cut-off date would be the filing date of the CIP and for the rest of the claim the search-cut-off date is considered as the earliest priority date.  

Moreover, if the complete target claim is falling under the scope of the newly added description, then for the whole claim the search cut-off date would be the filing date of the CIP.  

What is/are Considered as Prior-Arts in Invalidation? 

Before beginning the search, the analyst needs to know what patent/non-patent citations/references can be considered as a prior-art and for a US subject/target patent that would depend on US patent Laws. 

According to US Patent Laws: If the search cut-off date is before 16th March, 2013 then the Pre-AIA laws are applied and, if the search cut-off date is on or after 16th March, 2013 then the Post-AIA (AIA) laws are applied. 

All the citations satisfying the conditions of US patent laws can be considered as prior-arts. Wherein, the citations include patents, patent applications, non-patent citations/references. The non-patent citations/references can include research papers, thesis, standards, white papers, e-mails, conversations, newsletters, products, articles, videos, blogposts, any internet publications, etc. 

How to Invalidate a Patent? 

Invalidating a patent implies invalidating the claims or the independent claim of the subject patent. The analyst either locates a single relevant prior art which covers all the features of the claims or a combination of at least two prior-arts.  

Also, if a single independent claim of the patent is invalidated it implies that this particular claim of the patent is invalidated not the complete patent and all the other claims of the patent are still in force. In order, to invalidate the whole patent, all the claims of the patent would have to be invalidated. The prior arts herein are not only patents but also non-patent literatures which can also comprise of products/proof of sale. 

Also, the subject matter of the inventor himself can also act as prior art. US law provides a grace period to the inventors/applicants according to which they have one year to file a patent application once they have publicly disclosed their invention.  

In such a scenario, this/these document(s) will not act as a prior-art if it is published within one year of the date of filing of the patent application. However, if this document or another from same inventor exists one year before the filing date/priority date then it can act as a prior-art.  

Further, in case you encounter a document/patent having at least one different inventor than your subject patent inventors then that document is not required to be one year published before as this law of grace period will not be applicable. The document can act as prior art even if it is just filed before the search cut-off date. 

Note: The citations/references have to be published before the search cut-off date in order to be used in combination to invalidate a patent. 

How to Search for Prior-arts? 

The analyst can begin by extracting an exclusion list which includes list of citations (patents and non-patents) cited on the face of the subject patent and their family members. These citations are excluded from the scope of search generally but an exception can be made according to the client requirements.  

This also includes the list of citations cited by examiner during examination and are also discussed in the file history and from these patents we can get valuable insights of the technology and what types of citations should not be included in the search scope.  

One can also understand from the arguments in file history, the novel key elements and points that the applicant has tried to defend. Also, the file history includes examiner’s search strategies which can provide the analyst with ideas of constructing search strings/queries/strategies and some valuable keywords.  

Next, we can start with some freely available automated searching on Google or Google Patents which includes two options: a) Find Prior Art & b) Similar. Further, one can also use TTC’s in-house artificial intelligence platform Xlscout which comprises an invalidator tool where one may enter the patent number to be invalidated and it will automatically generate a bucket of patents.

Then we can perform some basic searches such as:

 This includes the bucket of patents generated by extracting the backward citations of the forward citations of the subject patent plus the forward citations of the backward citations of the subject patent. This bucket is then reduced by appending the search cut-off date and few classes or search keywords can also be used. We can perform Citation Analysis on any database. 

In this search the bucket including family members of the backward citations of the family members of the subject patent is extracted and the patents in the exclusion list are removed from the former bucket. The list of patents which are left can be analyzed in order to find relevant prior-arts.  

These automated/intelligent methods of searching are helpful in locating relevant prior-arts in a quick succession and also provides the analyst/researcher with deeper insights, keywords, synonyms and/or classes that can be helpful in steering the search further. Additionally, one may have certain citations that are already known to the client. This can provide the searcher with deep insights into the domain, the missing elements of the claim to be found, important assignees and classes etc.   

Further, in next step of searching the analyst can move to keyword and class based strategies/strings. These strategies can be created on various paid/free databases like Orbit, Derwent, XLSCOUT, Patsnap, Lens.org, Google patents, Google, IEEE, Google scholar, IETF standards, 3GPP standards, ETSI, Espacenet, J-platpat, KIPRIS, CNIPA, etc. These strategies go from narrow to broad using all the possible methods/key words/strings/phrases/classes to cover the claim scope. 

Next, the bucket of citations/references/patents/non-patents shortlisted by the analyst by the above searching process can be used in the following ways: 

These procedures of searching will keep on varying depending on various factors like the client requirements. project budget, or domain of subject patent etc. For example, for the telecom/wireless industry patents the standard searching will be incorporated and will play a major role. Next, these searches not only include a US jurisdiction, and the searches are conducted worldwide databases. 

Analyzing & Mapping Prior-arts: 

Refining your bucket of short-listed references/citations to the best/closest/bang-on available/identified citations is an important task. The citations are analysed with respect to every feature of the claims and the citations covering/having most/all the features of the claims are selected above the others in the domain from the bucket.  

Next, step for the analyst is to extract the relevant text and provide that in a particular format as per the client requirements which will provide the thorough/deep analysis of the bang-on/best/closest citations. This can be in the following two formats: 

 This type of mapping comprises providing relevant excerpts extracted from a relevant patent. The relevant excerpts may further be highlighted in correspondence to the claim requirements in a particular colour (for e.g. the relevant text is in red bold and the rest of the text is in black).  

This also include a searcher’s comment written in a lay man language for a quick understanding/brief about what all is present and not present in the mapped citation. This can also help the client understand if the analyst has inferred any equipment/apparatus/keyword etc. with what was required according to claims. 

In this type of format firstly the claims are broken down into key features/key elements and then the relevant text is provided for every key feature/key element of the claim. The text relevant to a specific feature is highlighted in a specific colour and the same goes for all the features. Further, searcher’s comments are provided for all the key features which help the client to deeply understand every key feature of the claim separately. Moreover, this format is helpful when we are using a combination of references to invalidate a claim(s).  

For e.g., if we are using a combination of two references and then from the mapping of the first reference the missing elements/features can be easily identified and the second reference covering those missing elements can be adjacently mapped to the first reference providing a clear and high-level analysis to the client. 

The summary type format is better when the duration of search/project is short and the number of references to be presented to the client or on the higher end. Whereas, the claim charted format provides a high-level understanding of a particular reference, on the other hand, it also consumes more time as compared to the summary type reports. 

Report Generation: 

Once the mapping of the bang-on/best/relevant citations is done these are incorporated in a report. The report can be in a word/excel/Pdf format. The report not only includes the best identified citations but the other closest possible citations or the other identified citations broadly related to the invention.  

These broadly related citations can be provided in a list with their bibliographic details. The report can also include a key feature analysis table which depicts which feature from a mapped reference is covered, not covered or has been inferred by the analyst which makes it easier for the client for a quick analysis of the mapped references.

In most cases, we prefer sending our clients interim reports which means reports at regular intervals during the project and then in the end a final report. This helps the client to know what has been identified at different phases/intervals of the search and about the search progress. Based on the interim reports the client can help the analyst steer the search according to their expectations/requirements.

The report is further quality checked at different levels including a project lead and then the project manager which ensures the reports of the highest quality are being forwarded to our clients. The quality not only includes the formatting of the report but also the high-level discussions of the identified and mapped references.

Client Communication: 

We also encourage regular discussions over the call or email with our clients in order to meet their requirements/expectations during the search or whenever they require our assistance. We usually start with a project initiation/introduction call/email with the client in order to know the expectations/requirements and criteria they want us to follow for the search.  

Further, the communications also include the report discussions for e.g., the interim reports are discussed with client(s) on regular basis or whenever required by the client and based on the inputs we steer our search accordingly. This keeps the search on the course so that no part is left out from the search. 

Cost of Invalidity Search

Invalidity search, also known as invalidation search or prior art search relates to performing a search on a patent (generally referred to as subject patent) in order to invalidate or kill or disable a patent.  

The invalidation search can be performed by independent searchers/researchers (free-lancers) or one can go to an organization to get the invalidation search done. There are various factors driving the cost to invalidate a patent. 

Who is Performing the Search? 

This is the first deciding factor in cost of the invalidation search. 

Now if one is going to free lancers/individuals, the cost will be less as compared to the organizations. But the search quality and standard of the search or depth of the search is definitely affected. 

This is for the organizations have a team of experts having vast and diverse expertise in various technology fields and thus can better understand the invention to be invalidated and there after performing a better search than an individual. Also, the organizations such as TTC, generally allocate or assign a bunch of people or a team for a particular case.  

The team will have searchers of different experience, a team lead who will look upon the search quality and references identified and who will make sure nothing is left behind. Also, there will be other people further enhancing the search quality, report quality and client interactions thus making sure that no stone is left unturned. 

While an individual may charge starting from 1000$ for invalidation search, the organizations generally begin at 2500$. This is the starting level of the search cost, and it may increase further depending on various other factors. Also note that this is not a standard or fixed value, and it may vary from individual to individual and from organization to organization.  

Complexity or Scope of the Search? 

The cost of invalidation search further depends upon the complexity of the subject patent invention, which becomes second deciding factor in determining the cost of search. Easy inventions that are simple in the domain and have less elements to be searched upon or we can say inventions that are easy and have smaller and simple claims and also the number of claims to be searched are less, can be done in a less budget.  

On the other hand, the inventions that are complex and belongs to a tough domain or have a greater number of claims elements requiring to be invalidated demands high budget. This is because the complex inventions will take a bit more time to understand, to develop search strings and to analyse the results of those search strings. 

Also, given that if an invention is complex or it has more number of claim elements to be searched upon, different and more number of search strings covering all the elements will have to be applied and analysed in order to cover all the possible prior arts. 

Therefore, on the basis of this second factor, the patent invalidation search may start from $2500 to a range that depends upon the complexity of the invention. 

Client Budget, Requirements & Expectations 

A third major deciding factor in deciding the budget of an invalidation search is client budget, timeline, requirements and expectations. Clients have different budgets and requirements that further depends upon various parameters. So according to their budget and requirements, the cost of invalidation search is decided.  

The clients decide or get allocated their budget as per the case complexity. In case, a subject patent in question is tough to invalidate and is undergoing various litigations, it is tough to invalidate such a patent. 

Also, when a patent undergoes an examination at the patent office before granting the patent, the extent of arguments and prior arts disclosed by the examiner and inventor himself determines the scope of finding prior art.  

A patent having a smaller number of known prior arts gives the searcher a broader area or a greater number of citations left out that could be used against the patent. But if a patent itself has many backward citations and further the examiner also identified various prior arts, the searcher has a bunch of prior arts to be excluded from the scope of the search making it harder for a patent to be invalidated. 


Non-Patent & Standard Based Search 

Moreover, in addition to patent search on various databases while performing invalidation search, a non-patent literature search is also performed that adds to the cost of invalidation search. The non-patent search may further be performed on various databases such as Google, IEEE, Science Direct, Springer, etc.  

The non-patent invalidation search may also comprise standard based search where the search is performed on various IETF, ITSE, 3GPP standards according to the scope of the invention. This non-patent search may start from 1500$. The standard search may additionally start from 1500$. 

Native Search 

The invalidation search may also be performed in different languages, i.e., the search strings and the search hits may be analysed in different country databases and in different languages. This is because some inventions are more covered, explored, researched or filed in certain countries. For example, an invention may have more literature in China than in Unites States

In such a case, it is wise to perform a Chinese native language search in order to not miss any prior arts that could work in invalidating the patent in question. Similarly, native Korean, Japanese language searches can also be performed.  

At TTC, we have experts in different countries who are fluent in different native languages and can perform native search on various databases. This would be an additional cost factor while deciding the budge of a particular search. The native search may start from $1500. 

At TTC, we justify our cost by giving the clients best quality and subject matter. We have experts in various field and technologies, in various countries in order to fulfil the client requirements and expectations. We also have experts having various research papers who have profound knowledge and expertise in the non-patent literature, thus performing the search on high levels. 

Search Report Format 

The budget or cost of invalidation search also depends upon a search report format that is chosen by the client. There are various search report formats (also discussed in detail below) that are used to present the search results. For example, one can provide a word report file comprising identified citations in a summary format along with searcher’s comment.  

One can also provide a word report file comprising detailed analysis of search results against the subject patent in question with each key element mapped with respect to the identified results along with a searcher’s comment. 

In another case, one can provide the same in an excel sheet where each identified patent is summarized or mapped against each key element of the subject patent claim(s). We can also provide simply highlighted PDF citations of the identified citations with relevant text being highlighted in order to save time in report making and allocating more time on searching. 

Further, we can provide the identified relevant citations in a table format along with their bibliographic details. So, we can say there are various search report formats that are chosen based on budget, client expectations and requirements. 

Generally, the simpler the report is, less time it takes to prepare it and hence less budget is required; and the more detailed a report is, more time it takes to prepare it thus requiring a higher budget. For claim charted reports, a minimum budget of 200$ is required in addition to the search budget.   

Who Performs Invalidity Search? 

Invalidity searches are performed by professionals hired by private firms. These firms (for e.g., TT consultants) registered firms and have professionals with deep knowledge in the IP industry. For all the searches a non-disclosure agreement (NDA) is signed and then the search is conducted by the hired professionals also known as IP/patent researcher’s/analysts. 

When it comes to performing invalidation search of any other IP search, a customer has various options. For example, the search may be performed by an individual or an organization. Whereas an individual can only offer a limited expertise in a particular technology or IP field, an organization has various employees having abundant IP experience and diverse expertise in different technology domains. 

When is a Patent Invalidity Search Needed? 

It is a prior art type search to check the validity/authenticity of patent claims or to invalidate a patent claim of an issued/enforced patent. It is date restricted search for finding out the prior arts disclosing the subject patent technology.  

The search is conducted to look/explore/discover for prior arts disclosing a claim language limitation rather than a subject invention as a whole. The search provides opposition to an already granted claim of a patent. The search provides a shield/defense/protection for an entity involved in a patent infringement case/lawsuit, by invalidating the claims of interest of the concerned patent. 

It is conducted to check whether an enforced/issued patent stands valid/legitimate for the following criteria/rules/laws: 

  1. Patentable Subject Matter
  2. Novelty
  3. Non-Obviousness

Grounds/Conditions/Reasons for the Search 

To conduct invalidity/invalidation/opposition search following grounds should be followed: 

  1. Presence of prior public information or use, or sale or publication of the patented technology, product, process, or service before the priority date of the subject patent, wherein the priority date is the earliest filing date of a patent in the patent office such as but not limited to USPTO, EPO, WIPO, IPO India etc.
  2. Objections/Rejections/Oppositions (for example in United States: 35 U.S. Code 101, 102, 103 rejections) made during prosecution or examination of the subject patent by the examiner.

Procedure/SOPs of the Search 

The following given below steps/procedures are adopted for conducting the invalidity/invalidation/opposition search. 

  1. Understanding the Subject Patent: This includes in-depth technical understanding of subject invention/technology disclosed in the patent.
  2. Understanding of Interested Claim Limitations/Elements: This includes understanding of claim language with respect to disclosure in the description of subject patent.
  3. Analysis of Prosecution History/File Wrapper: This includes understanding/analysis of non-final rejections, notice of allowance, and citations cited during prosecution of subject invention.
  4. Analysis of already Known Citations both Patent and Non-Patent: This includes analysis/understanding of citations (both patent and non-patent) cited (backward citations) on the face of subject patent.
  5. Conducting search queries for both patent and non-patent citations on search databases (both paid/open): This includes searching for prior arts (both patent and non-patent) on databases like Questel Orbit/ Thomson Innovation, Lexis Nexis (Total Patents), Google Patents, Google Scholar, IEEE Xplore etc.

Requirement/Need/Necessity for the Search 

This search is required during the life of the patent/patent term to check/determine whether a patent is novel or non-obvious. The need for this search arises due to the fact that sometime the examiner may miss some of the promising/relevant/good/potential prior arts due to some non-specific reasons such as time constraints, a load of applications or non-availability, etc. 

The given below are the reason when an entity/person/individual goes for a invalidity/invalidation/opposition search: 

Safeguard Against Patent Infringement/Protection Benefits: In this scenario the search is conducted by an entity to protect itself from an infringement lawsuit/case. The entity also known as defendant tries to search/dig/discover/uncover prior arts which are disclosing the claims limitation. The entity tries to find out prior arts (both patent and non-patent) which invalidate the concerned claims of infringement and safeguard itself form the monetary losses of patent infringement lawsuit.

Consider a company ‘A’ who has file an infringement lawsuit against a company ‘B’ for using its patented technology without informing or licensing out the technology from company ‘A’.  

In this case the company ‘B’ will conduct a patent Invalidity/Invalidation search for protecting itself from the infringement lawsuit filed by company ‘A’. The company ‘B’ will try to invalidate the claims of infringement for the patented technology of company ‘A’, so that it can be protected from the losses that can be occurred due to the infringement lawsuit. 

Analysis of Strength/Value of Patent For Licensing Opportunity/Opposition Benefits: In this scenario the search is conducted by an entity to check/validate/authenticate the claims of a enforced subject patent for analyzing its strength and value for evaluating its commercial benefits. This helps the entity to monetize the enforced patent for licensing/acquisition/merger benefits if the patent holds authentic/valid for novelty and non-obvious patent criteria/laws/rules. 

Consider a first company that wants to diversify/enhance/broaden its product/service portfolio by acquiring or merging with a second company having a patented technology that the first company is interested in.  

In this case, the first company will conduct a patent Invalidity/Invalidation search for checking the validity/authenticity/legitimacy of the patents of the second company, that the first company is interested in. Company ‘A’ will try to validate the patent claims of company ‘B’, for the criteria/laws/rules of novelty and non-obviousness.  

If the patent claims hold authentic/valid/legitimate for novelty and non-obviousness, then the company ‘A’ can invest in the licensing opportunities with company ‘B’.  

Validating the Subject Patent for Applying A New Technology in Same Domain: In this scenario, an entity/person/individual may conduct a prior art search to check the validation of the subject patent before applying for the invention in the same domain. 

Consider a company ‘A’ that wanted to file a patent in the same domain as that of interested subject patent. In this case the company ‘A’ may conduct invalidity/invalidation search so as to judge whether the subject patent can be a hurdle or not a hurdle to the entity filing for the new technology in the same domain.  

Why Invalidity Search? 

Invalidation search proves to be of help in various scenarios which are as briefed as follow: 

  1. Litigations: If a product is under a lawsuit or a litigation, meaning that if a plaintiff files a case against one’s product based on a patent owned by the plaintiff, then one can try to invalidate that patent and if that patent is invalidated, then correspondingly the litigation will not be enforced. This can save you from losing millions. 
  2. Petitions: IPR (Inter Partes Review) and PGR (Post Grant Review) can be filed against a granted patent under PTAB (Patent Trial and Appeal Board) in order to invalidate a patent or its claims. These trials are filed under some grounds which also include submitting prior-art. To find this prior-art for submission in these trials the applicant can go for an invalidation search of the patent against which the trial is to be filed.  

The major reason behind filing these are for example, if one is working in a technology area or field/domain and a rival company is granted a patent in the similar field/domain of invention; in order to get a strong hold in the field of technology, one can try to invalidate the patent by filing an IPR or a Also, if you want to launch a product which would infringe the claims of a patent then again, an IPR or a PGR can be filed to invalidate a patent. 

  • Validation: If a particular company or assignee wishes to make their owned portfolio stronger, they must know the values of their patents, thus they try to validate their own patent and the patent undergoes a validation search process and this can be called a validity search. Second, when a company wants to acquire another company’s IP/patents then they get their patents validated. 

Patent Invalidity Search Report 

The patent invalidity search report or patent invalidation search report or prior art search report is analysis of various references identified during an invalidation search that can be used against a patent to be invalidated.   


What is Invalidation Search? 

When a particular assignee or company (plaintiff) have a patent, or few set of patent(s) which they think are likely being infringed by a second company in the form of product or services which are being used commercially and are earning profit from the same; the company, inventor or assignee (plaintiff) files a case against the other company (defendant) using, commercialising and earning revenue from their patented invention. 

Now the defendant has two options: either settle the case by paying royalties to the plaintiff (whose patents are being infringed) or fight against the plaintiff where they prove that their product is on different lines than the patented invention.  

In another scenario, the whole case filed by the plaintiff can be nullified if the patent in question is itself invalid or should not have existed in first place. Yes, you heard it right. A granted patent can be nullified or killed or invalidated or disable if a prior art already exists before the filing date of the patent. 

Thus, if the defendants prove that the patent infringed can be disabled or invalidated, they won’t have to pay any royalties to the plaintiff even if their product is on same lines. 

Therefore, the defendant gets the patent in question searched from expert individuals or organizations such as TTC in order to identify prior art to kill the patent. 

How is Invalidation Search Performed? 

So once the organizations such as TTC receive a case where the client provides a subject patent to be invalidates, they allocate a team which performs search on various databases to identify promising arts. 

There are various steps performed in the search which are discussed and explored in detail in other pieces or this article. Generally, a patent and a non-patent search is performed in order to identify prior arts published or filed before the filing date of the subject patent with respect to various jurisdiction laws under consideration. 

Each jurisdiction has its own set of laws such as US laws, EP laws, etc. which decided whether a prior art can be used to invalidate a patent or not. So, a searcher must have profound knowledge of these laws while performing the invalidation search. 

Patent Invalidation Search Report 

Now once a searcher has almost exhausted the search budget and has performed extensive invalidation patent and non-patent search on a subject patent (patent to be invalidated), they shortlist a few numbers of citations (patent, standards, non-patents such as white papers, journals, research papers, you-tube or any informational video, etc.) that can be used against the subject patent. 

Each shortlisted citation is analyzed in detail with respect to subject matter and its credibility. The invention must fall under the laws set by various jurisdictions such as US laws, EP laws in order to invalidate a patent. If the subject patent is US, USC 102 laws must be taken into consideration while analysing a prior art.  

There are few parameters that once must check before analyzing or mapping a prior art in detail. These parameters are date criteria, assignee, previous assignments or reassignments, inventors, jurisdiction, priority country, etc.  

After analyzing in depth, the shortlisted identification of search, best prior arts are mapped in detail. The invalidation search report comprises detailed analysis of best prior arts with respect to the subject patent’s claims (independent, dependent or both). The invalidation search report helps the clients to better understand the identified prior arts in detail or reason behind how they can prove to be useful.  

There are various types of search report formats that can be used while providing the prior arts to the client depending upon budget, client requirements and expectations.  

Search Summary Report 

In case, the search budget is less or if the client just expects you to provide a simple format indicating the identification, one can go with simple search summary report. In this type of report format, the searchers provide identified citations with relevant text and a brief searcher’s comment that helps the client to better understand the searcher’s mindset or motivation behind providing those citations. 

The best citations are provided with relevant excerpts, bibliographic details and searcher’s comment. The relevant excerpts may further be highlighted in bold to map the prior art against the subject patent’s claim elements. 

In addition to the search summary report (word/excel/PDF format), the PDF copies of the mapped citations may also be highlighted as provided in a zip folder. 

This type of report is short and easier to prepare. It also consumes less time which the searcher can utilize to perform search. 

Here is a sample of such type of report that we use at TTC: 

This report comprises various sections such as list of identified citations (patent citations and non-patent citations), detailed analysis of the listed citations along with bibliographic details, relevant excerpts (highlighting with respect to target claim element) and searcher’s comment, other shortlisted citations.  

These citations are not as good as the citations provided in detail, but they are related to the field of invention and may prove to be useful for other secondary purposes such as understanding, combination of prior arts, etc. These citations are provided with bibliographic details and a short comment that gives the reason of them being listed here (for which key element, they can be useful). 

Claim Charted Report  

If the client wishes to have a detailed analysis of the prior arts identified in the invalidation search, these prior arts are provided by mapping in detail, relevant excerpts against each claim element of the claims of the patent to be invalidated.  

This type of report comprises a table with two columns. On the left-hand side, subject patent claims elements are put according to the key elements of claim and for all the claims that are required to be invalidated. On the right-hand side, each prior art is mapped with respect to each key element.  

The relevant excerpts from the identified prior art corresponding to a respective key element are put for all the elements. This also comprises short bibliographic details of the identified prior art along with a general searcher’s comment that gives a brief of the identified prior art. 

In addition, with respect to each key element, a searcher’s comment is also added that explains the mind-set of the searcher behind that mapping and also in case if there is any inference, that is explained so that the clients can understand the claim charts from searcher’s perspective. 

An example of such report is shown herein: 

A list of identified citations provides bibliographic details of the identified patent citations and non-patent citations. A detailed claim charted analysis of the findings with respect to the key elements of the claims of interest or target claims is provided.  

Brief bibliographic details and a short searcher’s comment for Other Shortlisted Citations which as not as good as the mapped citations but they cover few elements and hence may prove to be useful for some or the elements or for combination purposes. We can say that the detailed claim charted citations can serve as primary prior arts that can be individually or in combination used to invalidate a patent.  

In addition to this, a key feature analysis of the mapped citations is also provided. The Key feature analysis is a table that has three parameters – Yes, Inferred, No; for each claim key element with respect to the identified prior art.  

Yes represents that a particular feature is completely disclosed in the prior art, No represents that a feature is not disclosed in the prior art, and Inferred (sometimes also referred to as Yes*) represents that a particular feature is not explicitly disclosed, but it can be partially inferred from certain text in the identified prior art.  

An exemplary key feature analysis is shown herein: 

The key feature can be done for all the mapped patent and non-patent citations. Further, it is not necessary that only a claim charted report comprises key feature analysis. It can be the case, that the identified prior arts are provided with relevant excerpts and the searcher’s comment in a summary format, however, even then key feature analysis can help the clients to better understand how many or which elements of the subject patent claims are invalidated. 

This further helps the searcher and clients to have a better idea of which features are disclosed in the prior arts and which features are not disclosed in the prior arts or are not explicitly disclosed and thus require further search. A supplementary search can be performed in such a case with prime focus on the missing key features/elements of the claim. 

Why TTC? 

When it comes to performing invalidation search of any other IP search, a customer has various options. For example, one can get the search performed by an individual or an organization. Whereas an individual can only offer a limited expertise in a particular technology or IP field, an organization has various employees having abundant IP experience and diverse expertise in different technology domains. 

Now when coming to organizations, again there are various choices available these days, and one should choose the best. TTC by all means is one of the best and renowned organizations in IP searching. And this did not happen overnight, TTC has an IP experience of almost two decades providing excellent and satisfying services to our consumers. 

At TT Consultants, we apply intelligence to Intellectual Property (IP) globally. Our focus is to help clients solve their problems by providing useful strategies to them thus ensuring meticulous execution. We serve world’s largest companies, law firms, institutions, and several other IP fraternities. We help to monetize IP, defend IP litigation, lead innovation in industry and achieve most out of IP budgets.  

We have various long-term clients who always choose TT as their go-to firm for diverse projects. We offer various services such as:



We also specialize in patent portfolios, patent rankings and technology landscapes. We further offer market research as well. We have specialized and expert teams for patent drafting, prosecution, office actions, etc. 

TT Consultants is led by a highly experienced executive team committed to driving innovative solutions that deliver value to our clients. Our team comprises of 200+ experts in various technology areas such as electronics and communication, mechanical, pharma, biotech, life sciences, computer science, electrical and many more. Also, we have more than 25 PhDs with diverse expertise in various domains. We have 60+ experts having more than 10+ year of experience in IP.  

In addition to that, we have IP experts related to us from US, UK, Taiwan, Japan and Canada having vast IP knowledge. Few of our team members have also served as USPTO patent examiners, thus we provide you with best of everything. 

Also, we have our own in-house tools, XLPAT and XLSCOUT where the merging of human and machine learning gives best results. Humanizing intelligence from machine learning is primary foundation of analysis, insights, and informed decisions.  

Proprietary algorithms, using Artificial Intelligence and Machine learning, led to evolution of a machine designed to mimic behaviour of an expert searcher. Various data sets include Patent data, Non-Patent Literature, Standard Essential Patents, Litigation data, Corporate data, Reassignment data, and Examination data. 

About TT Consultants

We’ve constantly identified the value of new technology carried out by our pretty skilled executive crew with backgrounds as our professionals. Like the IP professionals we empower, our starvation for development is never-ending. We IMPROVISE, ADAPT, and IMPLEMENT in a strategic manner.
TT Consultants offers a range of efficient, high-quality solutions for your intellectual property management ranging from Patentability Search, Invalidation Search, FTO (Freedom to Operate), Patent Portfolio Optimization, Patent Monitoring, Patent Infringement Search, Patent Drafting & Illustrations, and much more. We provide both law firms and corporations in many industries with turnkey solutions.
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