Legal Definitions - closed-ended claim

A closed-ended claim, in the context of patent law, is a specific type of statement within a patent application that precisely defines the boundaries of an invention. It uses highly restrictive language, typically phrases like "consisting of," to indicate that the invention *only* includes the elements or steps explicitly listed and nothing more. This means that if a product or process contains even one additional component or step not mentioned in the claim, it would generally not infringe on that specific closed-ended claim.

This type of claim provides a very narrow but often strong scope of legal protection. While it offers less breadth than an "open-ended claim" (which uses phrases like "comprising" or "including" to allow for additional elements), a closed-ended claim can be valuable for inventions where the exact combination of specific elements is critical and distinguishing.

• Example 1: A Novel Beverage Formula

  Imagine a patent claim for a new soft drink that states: "A beverage consisting of carbonated water, natural lemon flavor, and stevia sweetener."

  How it illustrates the term: This is a closed-ended claim because it uses "consisting of." If a competitor creates a similar drink that includes carbonated water, natural lemon flavor, stevia sweetener, *and* a vitamin supplement, their product would likely not infringe this specific claim. The presence of the additional vitamin supplement means their product does not *consist solely* of the elements listed in the patent claim.

• Example 2: A Specialized Cleaning Process

  Consider a patent for a method of cleaning delicate electronics: "A method for cleaning electronic components consisting of the steps of applying an isopropyl alcohol solution, followed by air-drying at room temperature."

  How it illustrates the term: This claim is closed-ended due to the "consisting of" language. If another company uses the same isopropyl alcohol application and air-drying steps, but then adds a final anti-static wipe, their process would not infringe this particular claim. The additional anti-static wipe step means their method does not *consist solely* of the two steps outlined in the patent.

• Example 3: A Unique Medical Device Component

  Suppose a patent claims: "A surgical tool handle consisting of a titanium alloy core, a silicone grip, and a sterile plastic casing."

  How it illustrates the term: This is a closed-ended claim because it specifies that the handle *consists of* only these three components. If a different manufacturer produces a handle with a titanium alloy core, a silicone grip, a sterile plastic casing, *and* an embedded RFID chip for tracking, their product would not infringe this specific claim. The RFID chip is an additional element not included in the "consisting of" definition, thus placing it outside the scope of this narrow claim.