Federal Circuit Restores a Stricter AIA Priority Test for Prior Art

In a precedential decision issued on August 10, 2026, the U.S. Court of Appeals for the Federal Circuit in Dental Monitoring SAS v. Align Technology, Inc. rejected the PTAB’s broader approach to priority under the America Invents Act. The dispute turned on 35 U.S.C. § 102(d)(2): whether a later-published U.S. patent document can obtain an earlier § 102(a)(2) prior-art date merely because it formally claims priority to a provisional application and the provisional discloses the subject matter later relied upon as prior art.

The court said that is not enough. It restored the more demanding Dynamic Drinkware framework, requiring a showing that the earlier application provides § 112(a) written-description support for at least one claim of the later reference, in addition to supporting the subject matter actually used as prior art. In PTAB practice, that distinction can decide whether a key reference qualifies as prior art at all—particularly when the challenged patent’s effective filing date falls between the reference’s provisional and nonprovisional filing dates.

The ruling changes the threshold, not just the wording

Align relied on a U.S. patent publication referred to as Carrier in its obviousness case against Dental Monitoring’s ’409 patent. Dental Monitoring’s effective filing date, based on foreign priority, fell after Carrier’s provisional filing date but before Carrier’s nonprovisional filing date. Carrier therefore mattered only if it could reach back to the provisional date for purposes of § 102(a)(2).

The PTAB had followed its precedential Penumbra decision and treated AIA § 102(d)(2) as dispensing with the older Dynamic Drinkware requirement that at least one claim of the later reference itself be supported by the provisional application. On that view, formal compliance with the priority statutes, combined with disclosure of the relied-upon subject matter in the earlier application, could be sufficient.

The Federal Circuit disagreed. Reading § 102(d)(2) together with § 119(e)(1), it held that being “entitled to claim a right of priority” carries substantive requirements. For a provisional application, that includes compliance with § 112(a). The court therefore vacated the PTAB’s decision and remanded for further analysis of whether the Carrier provisional actually supports at least one published claim of Carrier.

Petitioners now need a two-part evidentiary chain

For a U.S. patent reference that depends on a provisional filing date, an IPR petitioner should now assume that two distinct showings are required. First, the provisional must provide adequate written-description support for at least one claim of the later reference. Second, the provisional must also support the specific disclosure being used in the anticipation or obviousness theory.

That changes how petitions should be built. A chart showing that the cited paragraph appears in the provisional is no longer a complete priority analysis. A more defensible record will map at least one later claim to the provisional on an element-by-element basis, then separately map the technical disclosure used as prior art. Thin provisional filings, generalized descriptions, or later-added combinations of features are obvious pressure points.

The burden is practical as well as doctrinal. Priority-page formalities will not carry the issue by themselves. Expert declarations, the provisional specification, the later claims and the relied-upon passages need to form a coherent support chain. In multi-reference obviousness cases, that can add meaningful front-end work and may affect which references are worth putting into the petition at all.

Patent owners gain a more targeted way to attack prior-art status

For patent owners, the decision creates a stronger route to disqualifying an asserted reference without first litigating every technical detail of the obviousness theory. When a key U.S. patent publication has a nonprovisional filing date later than the challenged patent’s effective filing date, but depends on a provisional or other earlier priority link to qualify under § 102(a)(2), counsel should examine more than whether the cited passage existed early.

The additional question is whether the earlier application supports at least one claim of the reference itself. That inquiry can be especially productive where the provisional was brief, where substantial technical detail appeared only in the later filing, or where the later claims combine concepts that were not presented together in the provisional.

If the earlier date fails, the reference’s prior-art date may move forward beyond the challenged patent’s effective filing date. In some proceedings that may remove a reference entirely; in others it may force the petitioner to rebuild an obviousness combination, add a different reference, or rework the motivation-to-combine theory. The calendar can become outcome-determinative.

USPTO guidance and existing IPR playbooks need recalibration

The decision directly conflicts with the broader approach associated with Penumbra and reflected in USPTO materials addressing AIA § 102(d), including guidance that had treated entitlement to the earlier date largely as a matter of priority compliance plus support for the relied-upon disclosure. After a binding Federal Circuit decision, practitioners should not treat that older formulation as a safe endpoint for analysis.

For petitioners, the practical response is to audit every core patent reference that depends on an earlier priority date before filing. If a reference is prior art only because of a provisional date, the § 112(a) support analysis should be completed at the outset rather than left for the patent owner’s preliminary response. Patent owners, in turn, should add “does the earlier filing support a claim of the reference?” to their standard priority challenge checklist and place their own foreign, PCT and U.S. priority dates on the same timeline as the petitioner’s references.

The ruling does not make provisional or foreign priority claims ineffective. It changes what must be proved before an earlier date can be used as an AIA prior-art date. A date printed in a priority chain is no longer enough on its own; the written-description link between the earlier filing, at least one later claim, and the relied-upon disclosure has to withstand scrutiny.