Literal infringement occurs when an accused product or process contains each and every limitation of a claim. This analysis is performed limitation by limitation, meaning that every specific requirement recited in the claim must be present in the accused product or process. Even if one limitation is absent or altered, there is no literal infringement. However, even if there is no literal infringement, there could still be infringement under the doctrine of equivalents. This article will address only literal infringement. To learn about Doctrine of Equivalents, read: The Doctrine of Equivalents: What Every Innovator Should Know.
Key Concepts in Literal Infringement
Limitations vs. Elements
Technically, there is a distinction between limitations and elements:
- Limitations refer to the words of the claim, whereas, elements refer to the accused infringing product. To use these terms in the proper context, one might say, “the receiver element in the accused product satisfies the receiver limitation of the claim of the patent.”
However, this rule isn’t strictly enforced. Courts often use the terms interchangeably. However, it’s helpful to make this distinction for clarity when analyzing infringement. Literal infringement requires that every limitation in the claim be found in a corresponding element of the accused product or process.
We will use the example claim below to help you understand literal infringement.
Example Claim: An Exercise in Identifying Limitations and Elements
Claim from U.S. Patent No. 9,914,063 (Fidget Spinner Toy):
Claim 1: A toy comprising:
- a central body having a central axis;
- a plurality of arms extending radially from the central body;
- a bearing assembly positioned at the central axis, allowing the central body and arms to spin relative to the bearing assembly;
- wherein each arm includes a weight at its distal end to facilitate spinning.
Breaking Down the Claim:
Here are a few of the limitations in the claim. As you can see, we are breaking down the language of the claims word-by-word. Each word has a meaning. This is how we ought to be treating the claims. If you’re thinking that this makes the claims narrow, it does but there are ways to broaden up claims. But, don’t worry about that at this point.
| Limitation | Claim Language Requirement |
|---|---|
| 1. Central Body | - A central body. - The central body must have a central axis. |
| 2. Radial Arms | - A plurality of arms. - The arms must extend radially outward from the central body. |
| 3. Bearing Assembly | - A bearing assembly positioned at the central axis. - The bearing assembly must allow the body and arms to spin. |
| 4. Weighted Arms | - Each arm must include a weight. - The weight must be located at the distal (outermost) end of the arm. - The weight must facilitate the spinning of the toy. |
Literal Infringement Analysis in a Spreadsheet
The table below demonstrates how literal infringement is analyzed for various claim limitations, using different scenarios for the accused product’s elements.
| Claim Limitation | Scenario 1: Device has B, C and D, but not A | Scenario 2: Device has A, C and D, but not B | Scenario 3: Device has all elements except C | Scenario 4: Device has all elements except D | Scenario 5: Device has all elements A, B, C and D |
|---|---|---|---|---|---|
| Limitation A: A central body having a central axis | Not present | Present | Present | Present | Present |
| Limitation B: A plurality of arms extending radially from the central body | Present | Not Present | Present | Present | Present |
| Limitation C: A bearing assembly positioned at the central axis, allowing rotation | Present | Present | Not Present | Present | Present |
| Limitation D: Each arm includes a weight at its distal end to facilitate spinning | Present | Present | Present | Not present | Present |
| Literal Infringement? | No | No | No | No | Yes |
Literal infringement requires that every limitation of the claim be present in the accused product or process exactly as written. The above scenarios demonstrate how even a single missing limitation precludes a finding of literal infringement. Infringement only exists in Scenario 5. No literal infringement exists for Scenarios 1-4. If you are thinking that you aren’t infringing the claim or that your competitor isn’t infringing, your analysis isn’t done yet. An analysis of whether there is infringement under the Doctrine of Equivalents needs to be performed. You can read my article on infringement under the Doctrine of Equivalents. For now, let’s dive deeper into literal infringement.
The Purpose of Understanding How Literal Infringement is Analyzed
Understanding how literal infringement is analyzed is critical in two main contexts:
- Drafting Claims and Specifications:
- When claims are drafted, the primary question is whether your competitors would literally infringe these claims if they were allowed.
- Analyzing Claims for Infringement:
- When asserting your patent, you want to assert that your competitor is literally infringing your claim because infringement under the doctrine of equivalent is much harder to establish.
If you’re navigating potential infringement issues or need help drafting patent claims that maximize protection, contact us today at (949) 433-0900 or schedule a consultation to discuss your strategy and safeguard your innovations.