Magnolia Medical Technologies Inc. v. Kurin Inc. Archives

AIA reviews: An alternative to litigation, not a second chance

Addressing the scope of discretionary institution under the America Invents Act (AIA), the United States Patent and Trademark Office (USPTO) denied institution of inter partes review (IPR), concluding that the petitioner was attempting to use the Patent Trial & Appeal Board as a “second bite at the apple” after unsuccessfully litigating substantially similar invalidity issues in district court, contrary to the AIA’s purpose of providing a streamlined alternative to litigation. Magnolia Medical Technologies, Inc. v. Kurin, Inc., IPR2026-00097, Paper 17 (Director May 14, 2026).

Magnolia challenged the validity of Kurin’s patent directed to a blood-testing device in district court. After the district court excluded Magnolia’s invalidity expert based on disclosure deficiencies related to claim construction and a jury subsequently found the patent not invalid, Magnolia filed an IPR petition asserting substantially similar anticipation and obviousness grounds. The Director denied institution, concluding that Magnolia had already had a full and fair opportunity to litigate those issues in district court and was improperly attempting to relitigate them before the Board.

The Director explained that Congress created IPRs and post-grant reviews (PGRs) under the AIA to provide streamlined and cost-effective alternatives to district court litigation, not to facilitate repetitive validity challenges or expand parallel litigation. The decision noted that, in practice, many petitioners pursue AIA review alongside district court litigation, sometimes asserting overlapping invalidity theories or taking inconsistent positions across forums, thereby increasing costs and burdening both patent owners and the USPTO.

The Director further emphasized that AIA proceedings serve broader public-interest objectives beyond resolving private disputes, including promoting efficiency, fairness, predictability, and the integrity of the patent system. In exercising discretionary institution authority, the USPTO considers factors such as examiner error, inconsistent positions across forums, settled expectations, and whether institution would represent an appropriate use of USPTO resources.

Applying those principles, the Director concluded that Magnolia’s petition fell outside the intended purpose of AIA review because Magnolia was not using the Board as an alternative forum for resolving validity disputes, but instead to relitigate substantially similar invalidity theories after an unfavorable outcome in district court. The Director emphasized that Magnolia had already contested validity in district court using anticipation and obviousness grounds similar to those asserted in the petition and that the parties had expended substantial resources litigating those issues.

The Director rejected Magnolia’s argument that institution was warranted because no tribunal had adjudicated the merits of its anticipation and obviousness theories after the district court excluded its expert testimony. According to the Director, Magnolia had a full and fair opportunity to litigate those issues, and the exclusion of its expert resulted from deficiencies within Magnolia’s control. Permitting institution under those circumstances, the Director explained, would improperly allow Magnolia to obtain a “second bite at the apple” before the USPTO.

In discussing the public-interest considerations that inform discretionary institution decisions, the Director highlighted several precedential and informative decisions addressing issues such as substantial examiner error, inconsistent positions across forums, foreign sovereign petitioners, and settled expectations. The Director explained that these decisions reflect [...]

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Separately recited structures must be separately present in accused device

The US Court of Appeals for the Federal Circuit explained (again) that when a claim separately recites multiple structural limitations, infringement requires separate corresponding structures. A single component that sequentially or multifunctionally performs the claimed functions is not enough. Magnolia Medical Technologies, Inc. v. Kurin, Inc., Case No. 24-2001 (Fed. Cir. Mar. 6, 2026) (Lourie, Hughes, Freeman, JJ.)

Magnolia Medical sued Kurin for infringement of two patents directed to devices designed to reduce contamination of blood samples by skin microbes during venipuncture. The claimed devices divert the initial portion of blood, which is most susceptible to contamination, into a separate reservoir before collecting the remainder of the sample. Kurin manufactures the Kurin Lock, which separates the initial blood sample from the remaining sample using a porous plug. That plug initially functions as a vent, allowing air to escape, and then expands as it absorbs blood, closing its pores and forming a seal.

The representative claim of one of the asserted patents recites a device comprising a fluid reservoir “at least partially defined by a seal member and a vent.” The representative claim of the other patent recites a “diverter.”

During claim construction, the district court construed “diverter” as a means‑plus‑function term under § 112(f). Because the Kurin Lock lacked a corresponding diverter structure, the parties stipulated noninfringement of that patent.

The district court did not expressly construe the “seal” and “vent” limitations of the other patent at Markman. At trial, however, the jury found that Kurin infringed that patent.

Kurin moved for judgment as a matter of law (JMOL), arguing that it did not infringe because the Kurin Lock did not include separate seal and vent structures. Instead, a single porous plug performed both functions at separate times. The district court agreed and granted JMOL of no infringement. Magnolia appealed.

The Federal Circuit affirmed, rejecting Magnolia’s argument that the district court had improperly adopted a new claim construction at the JMOL stage. While courts may not introduce a materially different construction after trial, they may elaborate on what is inherent in the plain and ordinary meaning of a claim. The Federal Circuit reiterated its prior holdings that when a claim separately lists structural limitations, the plain and ordinary meaning requires separate corresponding structures. Here, the district court merely clarified that requirement, it did not change the construction.

The Federal Circuit found that the asserted claim required separate structures. The use of “comprising,” the introduction of “a” before both “seal” and “vent,” and the use of “and” between them all pointed to distinct components. The specification further reinforced that the seal and vent were described as separate structures.

The Federal Circuit also affirmed the district court’s construction of “diverter” as a means plus function limitation. Although the claim did not use the word “means,” Kurin successfully showed that the term failed to recite sufficient structure, triggering § 112(f).

Practice note: This case is a reminder that when multiple structural elements are separately recited in a claim, courts are likely to require [...]

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AIA reviews: An alternative to litigation, not a second chance

Separately recited structures must be separately present in accused device

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