Claim construction refers to a set of rules that help determine the scope and meaning of a patent’s claims. These rules are essential for understanding what is and isn’t covered by a patent. Without them, writing, reading, and interpreting claims can feel frustrating and inconsistent. The good news? Once you grasp the rules, they become a reliable framework for navigating the patent process.
Why Claim Construction Matters
Claims are interpreted differently during examination and litigation, and understanding this distinction is critical. During patent examination, claims are reviewed under the Broadest Reasonable Interpretation (BRI) standard. However, during litigation, claims are interpreted using the ordinary meaning standard.
This difference in interpretation often confuses startups and inventors, particularly when an examiner cites prior art that seems irrelevant to the claimed invention. By understanding the rules of claim construction, you can avoid frustration and confusion and develop effective strategies for both examination and enforcement of your patent.
Broadest Reasonable Interpretation (BRI)
Under BRI, claims are interpreted as broadly as reasonably possible while remaining consistent with the specification. This standard ensures that:
- Claims are clear.
- Claims do not encompass prior art.
For example, if you claim a “flat” desk, the examiner might interpret “flat” broadly enough to include semi-curved surfaces because, in the real world, no surface is perfectly flat. This broad interpretation allows the examiner to consider more prior art, even those references that may seem only tangentially related to your invention.
During examination, encountering an office action that seems far-fetched or “off-base” is common. Instead of getting frustrated, consider the assumptions the examiner made under the BRI standard. This approach will help you understand how the examiner interprets your claims and guide your strategy for amendments.
If you need assistance with crafting claims or responding to office actions, feel free to reach out. Read more about my patent prosecution services.
Ordinary Meaning
In litigation, claims are interpreted according to their ordinary meaning, as understood by a person of ordinary skill in the art at the time of the invention. This interpretation:
- Narrows the scope of claims to their specific meaning within the context of the patent.
- Reflects the courts’ cautious approach to granting exclusive rights.
Returning to the “flat” desk example, an accused infringer could argue that their desk’s semi-curved surface does not infringe because “flat,” in its ordinary sense, excludes curved surfaces.
Practical Implications During Examination
To navigate these differing interpretations effectively, consider both BRI and ordinary meaning when writing and amending claims. Ask yourself these two key questions:
- Under BRI, does the claim amendment sufficiently distinguish the invention from prior art?
- Under ordinary meaning, is the claim broad enough to capture potential infringers?
If the answer to both questions is “yes,” the claim is well-balanced. If not, revisit the claim language to find a solution that satisfies both standards.
Rule 1 in Claim Construction: Use Internal Sources to Define Terms
The specification is the primary source for understanding what claims mean. It includes:
These elements collectively define the invention’s scope and clarify the context for interpreting claim terms. Always ensure the specification provides clear definitions and explanations for key terms to avoid ambiguity during both examination and litigation.
Rule 2 in Claim Construction: Use External Sources Sparingly
When the meaning of a claim term remains unclear after consulting the specification, external sources may be used. These include:
- Dictionary definitions.
- Technical literature.
- Expert testimony.
However, these external sources carry less weight than the intrinsic evidence (the patent itself) and should only serve as supplementary tools.
Avoiding Pitfalls
Navigating claim construction requires balance. Claims that are too broad during examination may be rejected based on unrelated prior art. Conversely, claims that are too narrow may fail to capture infringers during litigation. To avoid these pitfalls:
- Be mindful of how claim terms will be interpreted under both BRI and ordinary meaning.
- Use the specification to clearly define key terms and avoid ambiguity.
- Amend claims strategically to distinguish prior art without unnecessarily narrowing the scope.
Conclusion
Understanding claim construction is essential for successfully navigating the patent process. By keeping the dual standards of BRI and ordinary meaning in mind, you can better manage the challenges of patent examination and ensure that your claims remain effective in both avoiding prior art and capturing infringers. The key is to draft claims that strike the right balance, using the specification as your guide to communicate your invention clearly and effectively.