Why Are Claim Charts Required and Basics of How They Are Prepared

Claim charts are essential tools in patent law, particularly in cases of patent enforcement. Claim charts are a visual tool that can effectively present complex technical information clearly and concisely and significantly help to decide authorities/courts in the matters of Patent Litigation and help them understand the extent of infringement or non-infringement while studying every detail of the claim. A strong claim chart is supported by expert comments from an industry expert testifying the infringement of claimed features by the infringing product. It plays a key role in the swift movement of the case and helps both the plaintiff and defendants assess their position in a Patent Litigation.

How to prepare a claim chart?

A claim chart is a tabular representation of claimed features of a patent on one side and relevant excerpts from the product description/ product features on the other side to highlight how the infringing product is infringing every claimed feature of their patent. A well-structured claim chart requires a thorough understanding of patented technology and features of the accused potentially infringing product. Therefore, for preparing a perfect claim chart, along with the technical knowledge of the field of invention, a detailed understanding of marketing-related keywords is essential. Below are some key steps to identify an infringing product and prepare a claim chart.

Step 1: Understanding the Patented Technology and Identifying Potentially Infringing Products

Step 1.1: Understand the technology and define scope of claim

The first step is to thoroughly understand the patented technology and interpret scope of the claims using detailed description, prosecution history, and other extrinsic sources to ensure the broadest possible interpretation of claimed elements such that it covers a wide range of products. For this, identify the independent claims with the broadest scope of protection and interpret the claim in a way that maximizes its coverage while staying within reasonable bounds based on the detailed description of the subject patent and the knowledge of person skilled in the art.

Step 1. 2: Identify Application Area of Patented Technology and Type of products in which the patented technology can be employed

Examine patent to understand potential fields and industries where the patent technology can be applied. One may look into IPC/ CPC class code of the patent to locate the industry segment. Another way to understand the application area is by reviewing the technology field and products that are offered by the companies whose patents are cited in the subject patent’s citation list. Once the application area of the patented area is identified, the next step is to identify the type of potentially infringing products.

For example, if it is identified that the application area of a subject patent is Inertial Measurement Units, then the next step is to identify products that use inertial measurement units (ex. Mobile Phone, Smart Watch etc.).

Step 1.3: Identify Key companies and Evaluate potential infringement targets

The next step is to identify key companies that offer potentially infringing products and select those companies as potential targets for infringement analysis. This can be done through research to list key players in relevant technical fields and reviewing product specifications, industry reports and market reports to ensure comprehensive identification.

When selecting a target company for infringement analysis, consider additional parameters to ensure effective and beneficial patent enforcement. To avoid any potential conflict and complication, the target company should not have any existing licensing agreement or business relation with the Patent Owner.

Since patents are jurisdiction-specific rights, assess the presence and revenue of the target company in the preferred jurisdiction where the patent owner is interested in litigation. Specifically, focus on sales and revenue generated by the allegedly infringing product in the preferred jurisdiction.

Identify products of the target companies that are actively sold in the preferred jurisdiction and were launched after the filing date of the subject patent. If the patented technology relates to a specific feature of a product, identify the version of the potentially infringing product in which the patented technology was integrated.

Step 2: Claim charting  

Once it is established that the identified feature/ product was released after the priority date of the patent, commence a detailed analysis of potentially infringing product. Below are the type of sources that can be considered for preparing a claim chart:

2.1: Direct References:

The initial effort should aim to uncover all product-related official documents, datasheets, marketing material, video, audio, or any relevant document in any format pertaining to potentially infringing products, and released by the target company or its Executives/ Management team. Carefully validate the authenticity of the publication source and publication dates.

2.2: Indirect References

If direct disclosure of any claim element is not found, but the final or intermediate output or product feature suggests the presence of the concerned claim feature in the product, then all possible backend logic should be carefully evaluated to understand if the disclosed frontend feature/ description implies the use of claimed feature in the backend.

For example, if a patent covers a method of processing transactions using a specific encryption algorithm, and during claim charting it is observed that the product’s detail does not explicitly mention the use of this encryption algorithm. However, if the product documentation highlights a secure transaction feature in a way that is only possible by using the claimed encryption method, it should be highlighted and should be supported through expert comments citing appropriate logic/ arguments.

2.3: Standard Mapping

For SEPs, Two- step test for infringement is recommended and practical to locate pertinent documents related to products that reveal use of a Technical Standard, and map patent claims with a Technical Standard to establish that the patent is being infringed.

Alternatively, mapping the patent to a Technical Standard to show that the patent is and Standard Essential Patent, and then showing that the potentially infringing product also maps to the standard.

2.4: Source Code Review

The advancement in computer-related technologies and inventions has given significant rise to Patent enforcement and infringement actions that involve computer-related inventions. Since most of these inventions claim algorithms/ underlying logic, it becomes difficult to identify such features only by reviewing the product description, marketing material, or product itself.

In cases involving such technologies, Source Code Review plays a key role in uncovering the underlying algorithms and logic embedded within the computer-implemented product. By thoroughly examining the source code, analysts can gain insight into how the product functions at a deeper level. Source code review helps in tracing the flow of data and operations, understanding the decision-making process, and ascertaining how different components of the system interact with each other.

2.5: Tear Down Reports

For mechanical inventions or apparatus claims, teardown reports of products are the best way to determine whether a product is actually infringing on the patented claim. In teardown reports, every component of a device is dismantled to reveal the underlying parts and connections. Each independently identifiable part of the product is separated for detailed analysis.

Teardown helps to identify how the product is constructed and how it operates, allowing for a comprehensive comparison with the patent claims. For example, if a patent claim involves a specific type of hinge mechanism in a foldable smartphone as its core inventive concept, a teardown report would involve dissembling the potentially infringing foldable smartphone to expose the hinge mechanism for assessment and evaluation to understand if the hinge mechanism overlaps with the claimed hinge mechanism.

2.6: Reverse Engineering

In cases involving technologies related to fabrication of semiconductor devices and their underlying processes and structure, a reverse engineering report is the most effective way to ascertain patent infringement.

Reverse engineering a semiconductor chip is a challenging process that requires high-end sophisticated machinery and also demands highly skilled analytical expertise to analyze the layered structure of a semiconductor device. This process involves deconstructing logic gates, data paths, and layerwise analysis of a semiconductor device.

 2.7: Doctrine of equivalents

It is important to note that even after following the above steps, one might end up with an infringement claim chart that contains claimed elements that are not explicitly disclosed in the product description and were not discovered even using highly sophisticated processes like reverse engineering/ source code review.

For such cases, if the potentially infringing product or process does not literally infringe a patented invention, the accused product or process may be found to infringe under the doctrine of equivalents. The essential objective inquiry is: “Does the accused product or process contain elements identical or equivalent to each claimed element of the patented invention?”

In determining equivalence, an analysis of the role played by each element in the context of the specific patent claim will thus inform the inquiry as to whether a substitute element matches the function, way, and result of the claimed element, or whether the substitute plays a role substantially different from the claimed element.

Author: Sanjay Sharma, in case of any queries please contact/write back to us via email to [email protected] or at IIPRD.