The Essentials of a Due Diligence Checklist for Patents


Due diligence is a critical process that investors and stakeholders undertake to evaluate the value of a patent asset and any potential risks associated with it. A due diligence checklist for patents is a comprehensive list of items that should be reviewed during the due diligence process.

When conducting due diligence on intellectual property, it’s essential that the process runs as efficiently as possible. To do this, use a checklist to organize all collected information.

This checklist will highlight all of the essential factors that need to be evaluated during a patent investigation, helping you ensure you don’t overlook any important details along the way.

1. Identify the Patents-at-Issue

When a company purchases or licenses patents it must guarantee they remain valid and in good condition. This necessitates an extensive and meticulous investigation. A due diligence checklist helps the IP team organize their investigations efficiently.

How to identify patents-at-issue

Patent identification can be done through searching online or with a professional search tool. Furthermore, make sure to verify the patent status with both U.S. and foreign patent offices to confirm it hasn’t expired or been sold.

This is an essential step, as it can assist the purchasing company in avoiding infringement lawsuits and provide valuable insights into the product or technology being sold. Most published patents contain specific claims detailing both the method and equipment used for creation as well as instructions for using it.

Generally, the best way to locate patents-at-issue is by reviewing published and pending applications at the US Patent Office and other countries. This will give you all of the pertinent details about each patent in question and give an accurate assessment of how strong they are.

Once the patents-at-issue are identified, they should be thoroughly assessed to identify their strengths and weaknesses. This may involve reviewing their licensing agreements, assignment agreements, as well as litigation history. Due diligence on this type of project can be complex; thus, it is wise to enlist professional assistance from those experienced in conducting due diligence.

2. Determine the Protection Scope

A patents-at-issue due diligence checklist must be tailored specifically to the business transaction in question, as a general IP due diligence checklist will not suffice as it lacks the insight needed to make it useful for your company.

Once you’ve identified the products and technologies that are patented, it’s essential to determine their protection scope.

This can be a difficult task, as it necessitates an in-depth analysis of both prior art and patent claims. The patent officer must first assess for novelty – an innovative idea never seen before – then determine how closely related the invention may be to existing technology or other similar concepts.

The officer must also examine independent claims – those which do not refer to other claims. These are essential components of a patent application and it can be challenging to avoid obviousness if these do not accurately reflect the invention.

Importance of identifying the protection scope

Determining the protection scope of a patent necessitates an extensive analysis of its claims and specifications. This involves looking at how each claim is interpreted in court proceedings and applying those same claims to your target product. Patent claims must be precise and justified in their scope. This is an essential requirement of patent law that determines whether a patent will be valid or invalid.

It also helps determine any infringement risk associated with your target product while shielding your business from potential legal liabilities.

Besides, an essential consideration when defining a claim’s scope is the doctrine of equivalence. This well-established doctrine helps patent holders extend their protection and avoid infringement by specifying what functions essentially identically to their patented feature.

3. Examine the Patents-at-Issue

Before beginning a due diligence investigation, it is essential to identify and prioritize its objectives. Doing this helps keep the investigation on track and prevents it from deviating off course.

Once a goal has been identified, it’s time to evaluate the patents at issue. This involves assessing their scope of protection, the novelty of the invention, the strength of claims, and any invalidations that need to be addressed.

What a patents-at-issue investigation involves

When investigating patents-at-issue, the first step should be to review the prior art. This includes patents, applications for patents, published papers, and other documents relevant to the subject matter of pending or filed patents-in-suit.

Another essential element to review is the patents-at-issue’s litigation history. This is essential as it can expose hidden litigation issues that could lead to future lawsuits. Furthermore, you’ll gain insight into how those patents were handled during litigations and what strategies can be employed to safeguard your company’s patent portfolio going forward.

It’s essential to investigate the patents-at-issue’s ownership chain and maintenance fee issues. Failure to do so could devalue the patents in question and make them more challenging to defend in litigation.

As previously discussed, this aspect of IP due diligence can be overwhelming and time-consuming. That is why working with a team of knowledgeable intellectual property specialists who possess expertise in examining patents-at-issue and M&A transactions is so important.

4. Review the Patents-at-Issue’s Litigation History

A patent’s litigation history can be an important factor when assessing whether it’s worth investing time and resources into it. This is because lawsuits against patents may take years to resolve, with potentially severe financial repercussions.

In the past, patent infringement claims have often been dismissed in court. However, over the last decade or so, plaintiffs have seen more success in obtaining settlements for these matters.

As a result, plaintiffs and their attorneys have focused more on the technical aspects of patent litigation. This includes requesting discovery (interrogatories, depositions, etc.) as well as making pre-trial motions.

Filing a petition for patent validity review

Aside from discovery, parties may file a petition for patent validity review with the United States Patent and Trademark Office’s Patent Trial and Appeal Board (PTAB). This process, known as inter partes review (IPR), was instituted by Leahy-Smith America Invents Act of 2012. IPRs have become an increasingly common part of patent litigation due to their convenience and cost-effectiveness compared with traditional cases.

When filing for a patent, it must include an extensive specification outlining the invention in sufficient detail for others to make, use and sell it without violating the patent. Furthermore, the specification should list out claims which define and limit core elements of the invention.

It is essential that claims are written consistently and specifications match them, as this will help guarantee a judge’s accurate interpretation. For instance, claim terms like “host interface” should not be used in such a way as to require direct bus connection with the patented invention as in Inpro II Licensing S.A.R.L v. T-Mobile USA Inc.6, where T-Mobile was successful in federal court.

5. Examine the Patents-at-Issue’s Ownership

One of the most essential steps in a patent due diligence checklist is confirming who owns the patents at issue. Doing this helps avoid future lawsuits and guarantees that the correct party owns the patent. In US law, patents typically go to the inventor who then holds onto it until they assign it to another company or individual.

Therefore, it’s essential to investigate the inventors’ legal and business entities and confirm they own the patents in question. This can be accomplished through an extensive review of their assets and filing history.

It is also beneficial to review any licensing agreements and confidentiality agreements in place. These documents can indicate if the inventor remains affiliated with the company and has any connections to the current management team.


A due diligence checklist for patents should cover all essential items to evaluate the patent assets and potential risks associated with them. A thorough due diligence process is critical for investors and stakeholders to make informed decisions about patent assets. It is also essential to assess the status and validity of each patent as well as its enforceability, novelty, and uniqueness. This step of due diligence can take up a considerable amount of time during its investigation. A comprehensive checklist will ensure that all relevant information is reviewed and documented, providing a clear picture of the patent’s value and any potential risks.