Federal Circuit Rejects Penumbra's Test for Provisional Prior-Art Dates in Dental Monitoring SAS v. Align Technology

On August 10, 2026, the U.S. Court of Appeals for the Federal Circuit issued a precedential decision in Dental Monitoring SAS v. Align Technology, Inc., No. 2025-1752, fundamentally changing how the Patent Office and litigants determine the prior-art date of a patent or published application that claims priority to an earlier provisional application.

Under 35 U.S.C. § 102(a)(2), a patent or published application is prior art as of the date it was 'effectively filed,' and § 102(d)(2) allows that date to reach back to the filing date of the earliest application in a priority chain — provided the reference is entitled to claim priority and the earlier application describes the subject matter relied upon. In the pre-AIA case Dynamic Drinkware, LLC v. National Graphics, Inc. (Fed. Cir. 2015), the Federal Circuit held that a reference does not get its provisional's filing date merely by claiming it: the provisional must supply § 112 support for the claims of the reference itself, and the party relying on the reference bears the burden of proof.

For post-AIA patents, however, the USPTO had been applying a looser rule, reasoning that the statute requires only that the reference be 'entitled to claim' priority and that the earlier application 'describe the subject matter' used in the rejection — dropping the requirement that any claim of the reference actually be entitled to the earlier date. That approach was embedded in the PTAB's precedential decision in Penumbra, Inc. v. RapidPulse, Inc. (IPR2021-01466, decided March 10, 2023). In Dental Monitoring, the Federal Circuit rejected the agency's post-AIA approach, held that the Dynamic Drinkware rule carries over to § 102(d)(2), and overruled Penumbra.

The consequences are significant for both examination and litigation. Patent owners now have a new avenue to disqualify prior-art references whose earlier effective dates depend on provisional filings that do not support the reference's own claims. Although the decision centers on priority to U.S. provisional applications, commentators note the same logic should extend to references claiming priority to foreign filings — covering the two principal ways patents claim priority.

Practitioners expect the decision to reshape strategy in inter partes review and district court validity disputes alike, as parties re-examine priority-chain evidence for key references. The ruling also lands amid a broader recalibration of PTAB practice under USPTO Director John Squires, including the Office's pending final rule on IPR institution.

Original Link: https://www.womblebonddickinson.com/us/insights/alerts/federal-circuit-rejects-penumbras-ministerial-test-provisional-prior-art-dates