In re Incept — Federal Circuit Corrects Overbroad “Flow Barrier” Construction

Background

Incept sought a patent on a medical catheter with an anchoring strain-relief member. Claim 1 required ridges forming a “flow barrier” between the catheter’s outer surface and the top of each ridge, along with a sealing portion having a specified taper. The examiner rejected the claim as obvious over an earlier catheter reference known as Thompson Smith.

The Patent Trial and Appeal Board agreed. It treated the claimed flow barrier as any solid structure positioned somewhere within the stated bounds and concluded that the prior art disclosed every feature except the taper angle. Incept argued that the claim and specification instead required a barrier that actually spans the full distance and blocks flow.

The Court’s Holding

The Federal Circuit vacated the rejection and remanded. Even under the broadest-reasonable-interpretation standard used during patent examination, claim language must be read consistently with the specification. Here, the words “between” the catheter surface and ridge top, together with repeated descriptions of sealing and anchoring, required a solid surface spanning from the catheter’s outer surface to the top of the ridge along the relevant circumference.

The Board’s construction was too broad because it permitted fluid channels between the supposed barrier and the catheter surface. That reading conflicted with the specification’s description of a fluid-tight seal. The panel rejected the Patent Office’s argument that dependent claims using more specific sealing language justified its broader construction; those claims addressed configurations involving contact with an elastomeric member and did not erase the structural meaning of “flow barrier” in claim 1.

The claim-construction error undermined the obviousness analysis. The Board had assumed that taper angle was the only structural difference between the claim and Thompson Smith. Because that premise depended on the incorrect reading of “flow barrier,” the panel did not decide obviousness itself and sent the application back for a new patentability determination under the correct construction.

Key Takeaways

• The broadest reasonable interpretation is not the broadest imaginable reading; it must correspond to how the specification describes the invention.
• Functional context such as sealing can help define the required structure when the claim language and specification point in the same direction.
• An incorrect claim construction requires reconsideration of obviousness when it changes what the prior art must disclose.
• The ruling does not grant Incept a patent; the PTAB must reassess claim 1 on remand.

Why It Matters

Patent applicants often face expansive readings during examination. This opinion reinforces that the Patent Office cannot detach a disputed term from the invention the specification actually teaches. When a construction makes the recited structure incapable of performing the repeatedly described role, it may no longer be reasonable.

For medical-device drafting and prosecution, the case also illustrates the value of describing how structural features interact. The specification’s fluid-tight-seal discussion supplied the context that narrowed “flow barrier” and reopened the patentability analysis.