Patent Case Summaries August 17, 2022

Patent Case Summaries | Week Ending August 12, 2022

A weekly summary of the precedential patent-related opinions issued by the Court of Appeals for the Federal Circuit and the opinions designated precedential or informative by the Patent Trial and Appeal Board.


In re McDonald, No. 2021-1697 (Fed. Cir. (PTAB) Aug. 10, 2022). Opinion by Cunningham, joined by Newman and Stoll.

McDonald filed a patent application for methods and systems related to the display of primary and secondary search results in response to search queries. The examiner rejected the claims as being directed to patent-ineligible subject matter under 35 U.S.C. § 101 because they did not recite a “processor” for conducting the claimed searches. McDonald then amended the claims to add a processor, and the patent issued.

McDonald also filed a continuation application that likewise included “processor” limitations. McDonald later filed a reissue application seeking to broaden those claims by removing the “processor” limitations. The examiner rejected the claims, and McDonald appealed to the Patent Trial and Appeal Board. The Board also rejected the claims and, in doing so, entered two new grounds of rejection. First, the Board rejected the claims as being based on a defective reissue declaration. Second, the Board rejected the claims as impermissibly attempting to recapture subject matter that the patentee intentionally surrendered during prosecution to overcome the § 101 rejection. McDonald appealed.

The Federal Circuit affirmed, ruling that McDonald “cannot now use the reissue application as a Trojan horse to recapture that which he deliberately gave up.” That rule applies not only in the context of prior-art rejections, but also in the context of a § 101 rejection as occurred here. The Federal Circuit expressly refuted McDonald’s argument that § 101 rejections should be treated differently, stating: “We reject the argument that the recapture rule leaves a unique gap that would permit the recapture of claim scope surrendered in response to § 101 rejections.”

The Federal Circuit thus ruled that the Board properly applied the recapture rule to bar McDonald’s attempt to reclaim claim scope surrendered during prosecution. McDonald had “deliberately—not erroneously or inadvertently—added the ‘processor’ limitations during prosecution of the original claims to overcome the § 101 rejection,” and “the recapture rule does not permit him to now remove those limitations to broaden his claim.”

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Hologic, Inc., et al. v. Minerva Surgical, Inc., Nos. 2019-2054, -2081 (Fed. Cir. (D. Del.) Aug. 11, 2022). Opinion by Stoll, joined by Clevenger and Wallach.

In 2015, Hologic sued Minerva for patent infringement. During the case, Hologic moved for summary judgment arguing that assignor estoppel bars Minerva from challenging the patent claims’ validity in district court because one of the inventors (Mr. Truckai) had assigned his interest to Hologic before departing to found Minerva. The district court agreed with Hologic and entered summary judgment of no invalidity.

On appeal, the Federal Circuit held that the district court did not abuse its discretion in applying the doctrine of assignor estoppel. Minerva then petitioned the Supreme Court for a writ of certiorari, arguing that assignor estoppel finds no support in the Patent Act or the Court’s decisions. The Supreme Court declined to discard assignor estoppel but clarified that the doctrine “comes with limits.” In particular, assignor estoppel “applies only when an inventor says one thing (explicitly or implicitly) in assigning a patent and the opposite in litigating against the patent’s owner.”

The Supreme Court also considered Minerva’s contention that estoppel should not apply because the challenged claim was materially broader than the claims that Mr. Truckai had assigned to Hologic. The Court ruled that if Hologic’s new claim “is materially broader than the ones Truckai assigned, then Truckai could not have warranted its validity in making the assignment,” and “without such a prior inconsistent representation, there is no basis for estoppel.” The Supreme Court then remanded to the Federal Circuit to address whether the claim asserted by Hologic is materially broader than the ones Mr. Truckai had assigned.

On remand, the Federal Circuit held that the asserted claim was not materially broader than the claims Mr. Truckai had assigned. First, despite the claim being canceled two years prior to the assignment, it was without prejudice in response to a restriction, after already being allowed. Therefore, after considering the intrinsic record, the Federal Circuit held that the asserted claim was not materially broader and therefore affirmed the district court’s summary judgment that Minerva is estopped from challenging the claims’ validity based on the doctrine of assignor estoppel.

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LSI Corp., et al. v. Regents of the University of Minnesota, No. 2021-2057 (Fed. Cir. (PTAB) Aug. 11, 2022). Opinion by Dyk, joined by Reyna and Hughes.

The Regents of the University of Minnesota sued LSI for infringement of a patent that addresses error rates related to recording data to computer storage devices. LSI then petitioned for IPR of the patent, and the Patent Trial and Appeal Board initiated review as to claims 13, 14, and 17 based on anticipation theories.

In the final written decision, the Board found that claim 13 was unpatentable in view of “Okada,” and LSI elected not to appeal that ruling. As to claims 14 and 17, the Board found that LSI failed to show unpatentability for two reasons. First, the Board found that LSI’s argument based on anticipation by Okada was “improper as untimely” because it was raised for the first time at the Board hearing and, in any event, was unpersuasive. Second, the Board found that the “Tsang” reference was not prior art because it was not “by another” under 35 U.S.C. § 102(e).

On appeal, the Federal Circuit observed that LSI did not appeal the Board’s untimeliness determination. LSI argued that doing so was not necessary because the Board nevertheless reached the merits. The Federal Circuit disagreed. Thus, the court affirmed the Board’s conclusion based on Okada “because LSI forfeited any challenge to the untimeliness holding by failing to challenge it in its opening brief on appeal, and the Board’s timeliness holding constitutes an independent ground for its decision.”

Next, the Federal Circuit determined that the Board did not err in rejecting LSI’s anticipation theory based on Tsang. In so ruling, the court ruled that the relevant portions in Tsang relied on by LSI do not describe an invention “by another.”

The pertinent portions of Tsang summarized and relied on an earlier work—an industry report called the Seagate Annual Report—authored by Dr. Moon and Dr. Brickner, who were also the only named inventors on the patent being challenged. LSI argued that it relied on Tsang, not the Seagate Annual Report, to establish anticipation, and Tsang was “by another.” But the Federal Circuit rejected that notion. According to the court, “Tsang’s summary of, and reliance on, the earlier work of Dr. Moon and Dr. Brickner does not make Tsang an inventor of the earlier work.” If the rule were otherwise, then “a party challenging a patent could artificially alter the inventive entity for comparison by citing extraneous portions of a multi-inventor prior art reference, thereby making it ‘by others’ even if the portions of the reference necessary for establishing [invalidity] had the same inventive entity as the challenged patent.”

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Kamstrup A/S v. Axioma Metering UAB, No. 2021-1923 (Fed. Cir. (PTAB) Aug. 12, 2022). Opinion by Reyna, joined by Mayer and Cunningham.

Axioma petitioned for IPR of a Kamstrup patent directed to ultrasonic flow meters and housings. In a final written decision, the Patent Trial and Appeal Board found all of the claims unpatentable as obvious or anticipated.

In connection with that finding, the Board construed certain claim limitations. First, it construed “cast in one piece” as a product-by-process limitation that did not impart patentable weight to the claims. Additionally, the Board construed the phrase “cavity separated from the flow tube” to require that the interior of the flow tube be separated from the surrounding cavity by a shared wall. The Board rejected Kamstrup’s argument that the cavity cannot surround the flow tube.

Based on those constructions, the Board found that the “Ueki” reference anticipated many of the challenged claims, and that Ueki in combination with other references rendered the remaining claims obvious. Kamstrup appealed, focusing primarily on the Board’s claim constructions.

The Federal Circuit affirmed. The court ruled that the Board properly construed the phrase “cast in one piece” as a product-by-process claim element because it describes a structure that is cast in a particular way. Also, the court agreed with the Board that the term does not impart patentable weight to the claims. According to the Federal Circuit, Kamstrup failed to show “that the process claimed imparts structural and functional differences distinguished from the prior art.”

Turning to the claim phrase “cavity separated from the flow tube,” the Federal Circuit rejected Kamstrup’s argument that the term means the cavity cannot surround the flow tube. The court explained that Kamstrup’s position “reads in a negative limitation that is at odds with the claim language.”

Based on those claim constructions, the Federal Circuit upheld the determination of unpatentability. The cited references qualified as analogous art, and Kamstrup’s remaining arguments were tied to its claim construction positions.

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