How to Write a Patent Claim

Q: What is a patent claim?

A patent claim is a legal statement that defines what an invention does and what it protects. It determines the scope of your patent rights.

Q: How do I write a good patent claim?

A good patent claim is clear, specific, and supported by the rest of your application. Start with an independent claim, then add dependent claims for variations.

The claim section is the most important part of any patent application. It defines the exact scope of your legal protection—and if written poorly, it can make your patent weak or even unenforceable.

What Is a Patent Claim?

A claim is a single sentence that legally describes your invention. It answers the question: "What exactly am I trying to protect?"

Patent claims must be:

Precise
Clear
Technically supported by your description

Types of Patent Claims

Independent Claim: Stands on its own and defines a broad version of the invention
Dependent Claim: Refers back to an earlier claim and adds more details or limitations

Example:

Claim 1: A chair comprising a seat and four legs. (independent)
Claim 2: The chair of claim 1, wherein the legs are made of bamboo. (dependent)

Basic Structure of a Patent Claim

Most claims follow this pattern: 1. A preamble (introduces the invention) 2. A transitional phrase (e.g., "comprising", "consisting of") 3. A list of elements or steps

Example: "A wireless charging device comprising a power transmitter and a power receiver configured to transfer energy through inductive coupling."

Tips for Writing Strong Claims

Use broad language in the independent claim (but not too broad)
Add specific dependent claims to cover variations
Avoid unnecessary technical jargon
Make sure every claimed element is explained in the description

Common Mistakes to Avoid

Making the claim too vague or abstract
Including features that aren’t in the drawings or description
Using inconsistent terminology (e.g., "sensor" vs "detector")
Copying from other patents without understanding the language

Do You Need a Lawyer?

You don’t have to hire one, but drafting claims is difficult to do well. Consider hiring a Patent Attorney or Patent Agent if:

The invention is valuable
You're filing internationally
You're new to patent writing