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Patent Infringement Search: What You Need to Know

What is a patent infringement search?

A patent infringement search, also referred to as “evidence of use search (EoU)” is aimed at identifying potential infringing products or services against a particular patent. It provides evidence or indications that a product, process, or service is being used or sold in the market without the patent owner’s consent.

It is an essential tool for patent owners, especially those considering or preparing for patent enforcement or litigation, licensing negotiations, or even the sale of their patents.

What is patent infringement?

To understand how “evidence of use” can prove patent infringement, it is necessary to understand what patent infringement entails. 

A patent grants the holder the exclusive right to stop or prevent others from “commercially exploiting” the invention described in the patent claims for a certain period of time. 

Patent infringement occurs when another party makes, uses, sells, or offers to sell the patented invention without permission from the patent holder during the validity of the patent.

Direct infringement is described by 35 U.S. Code § 271 (a) as:

… whoever without authority makes, uses, offers to sell, or sells any patented invention, within the United States, or imports into the United States any patented invention during the term of the patent therefor, infringes the patent.”

An evidence of use search can prove infringement by showing that the product or service offered by the alleged infringer falls within the scope of one or more claims of the patent. As patent rights are territorial, each jurisdiction might define patent infringement differently.

While USC Code 271(a) describes what is called direct infringement, indirect infringement also occurs either through induced infringement or contributory infringement.

Induced Infringement occurs when a party induces or encourages another to infringe a patent, typically by actions, instructions, or other forms of encouragement. For example, if a company sells a product with explicit instructions to use it in a way that infringes a patent, that company may be liable for induced infringement, even if the product itself doesn’t directly infringe.

Contributory infringement happens when a party contributes to another’s act of direct infringement by supplying a component or means to facilitate the infringing act, but doesn’t directly commit the infringement itself.

What is in a patent infringement search or EoU search report?

While the contents of an EoU or patent infringement search report may vary, the core component are the claims mapping or patent-to-product mapping charts.

An EoU claim chart is a detailed breakdown that maps specific elements of the patent claims to the features of components of the potential infringing product, process, or service.

Where can I find evidence of use?

Evidence of use can take many forms, such as:

  1. Sales and Marketing Materials. Brochures, websites or promotional materials may describe the functionality of a product or service that directly corresponds to the patent claims.

  2. Product Specifications. User manuals, technical documentation such as schematics, system diagrams, or product specifications can provide evidence of use if they show components or processes that match the patent claims. E-commerce websites such as Amazon, Alibaba, etc can be a good starting point.

  3. Public Disclosures. Exhibitions at trade shows, presentations, interviews that describe the use of the patented technology can serve as evidence.

  4. Actual Products or Services. In some cases, the product or service itself may serve as evidence, especially if it can be shown to incorporate the patented technology when used or examined.

  5. Third-party Documentation. Industry reports, reviews, or other third-party documents that describe the product or service can provide evidence of use.

An evidence of use (EoU) search is a systematic process that requires a deep understanding of the patent in question and the technologies and products that potentially infringe upon it. 

Here’s a basic framework on how to conduct an EoU search:

1. Break down the patent claims Start by thoroughly understanding the patent(s). This involves studying the patent claims, which are the legally enforceable part of a patent that define the boundaries of the protection the patent offers. This is also the point where you need to visualize  and break down your search requirements by listing all the relevant keywords.
2. Identify potential infringers To start with a more narrowed down search, identify products, services, or processes that might potentially infringe upon the patent claims. Start with top companies and then entities within the same industry. If the elements claimed in the patent may have broad applications or other uses outside of its industry, list down all possible related industries and companies.
3. Gather documents, evidence of use Once potential infringers have been identified and the patent claims mapped, collect evidence of use. This can involve obtaining and analyzing product manuals, specifications, white papers, marketing materials, and other publicly available information that describe the potentially infringing features or components.
4. Map patent claims to products or processes For each potential infringer identified, map the claims of the patent to the potentially infringing product or process. This involves identifying features or components in the product or process that correspond to each element of the patent claims.
5. Get expert help In all these steps, a key factor is the interpretation of the patent claims, which can be complex and often require the input of legal and technical experts. It is beneficial to engage patent professionals, such as patent attorneys or patent researchers, who have the technical expertise to understand the patent and the legal knowledge to interpret patent claims. Find out how we helped a U.S. telecom giant monetize their patents.

An EoU or patent infringement search can be a time-consuming and complex process, but it is a critical part of enforcing patent rights. It is an important tool in licensing negotiations and in determining the value of a patent portfolio.

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1. Parola Analytics and Avontis are distinct entities and operate independently. Any references to Avontis or its services do not constitute a legal partnership. 

2. Parola Analytics does not provide legal services. Our services are limited to research and technical analysis. Any information provided by Parola Analytics should not be construed as legal advice.