Aseptic Patent Law: Which Side of Literal do you Favor?

Jan 30, 2024

by Dennis Crouch

Steuben Food recently lost its infringement case against Shibuya Hoppmann with the district court holding (1) the doctrine of equivalents (DOE) cannot extend to cover the accused aseptic bottle filling technique and further (2) the reverse doctrine of equivalents shields the defendant against charges of literal infringement. Steuben Foods, Inc. v. Shibuya Hoppmann Corp., No. 1:19-cv-02181-CFC, 2023 WL 2498810 (D. Del. Mar. 14, 2023) (U.S. Patent Nos. 6,209,591; 6,536,188; and 6,702,985) (Chief Judge Connolly). The case is now pending on appeal at the Federal Circuit with the successful defendant’s responsive brief due in mid-September.

There is fierce competition in the bottling industry, and Shibuya sold bottling lines to a major Steuben customer. Steuben sued Shibuya on three patents and initially won with a jury awarding $38 million in infringement damages. However, Chief Judge Connolly rejected the jury verdict by issuing a Judgement Notwithstanding the Verdict, holding that no reasonable jury could have found infringement. The rules of civil procedure now identify JNOV as the perhaps more politically correct name of Judgment as a Matter of Law (JMOL). The new name avoids the inconvenient truth that the process involves the rejection of a constitutionally protected jury decision.

Based upon what I’ve read — that admittedly does not yet include the appellee’s brief — I would side with Steuben Foods in this one. Judge Connolly was too aggressive at rejecting the jury verdict of infringement; too aggressive at applying the vitiation doctrine to a single word within the claim; and too aggressive at applying the long dormant reverse doctrine of equivalents.

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Judge Connolly’s JMOL decision turns on two controversial patent law doctrines – the doctrine of equivalents and its inverse, the reverse doctrine of equivalents.

Doctrine of Equivalents

The doctrine of equivalents allows a patentee to establish infringement, even when an accused product or process does not literally fall within the claims of the patent, if the accused product or process contains only insubstantial differences from the patent claims. The Supreme Court recognized the doctrine of equivalents in Graver Tank & Mfg. Co. v. Linde Air Products Co., 339 U.S. 605 (1950), explaining that it operates to prevent copying that makes only minor, insubstantial changes to avoid the literal scope of the claims. The doctrine is justified on the basis that language has inherent limitations in capturing the true scope of an invention, so equivalents help protect the inventor and promote innovation. However, the doctrine is controversial because it expands patent scope beyond literal claim terms, reducing public notice and potentially ensnaring later-developed technologies in infringement. The Supreme Court placed key limitations on the doctrine in Warner-Jenkinson Co. v. Hilton Davis Chemical Co., 520 U.S. 17 (1997), requiring equivalence to be assessed on an element-by-element basis and prohibiting vitiation of claim limitations.

Steuben’s ‘985 patent covers a sterilization machine and includes the following element: “wherein said atomized sterilant is intermittently added to said conduit.” Claim 1 (emphasis added). The problem though is that the accused device was shown to add the sterilant continuously. Although the jury found infringement by equivalents, the district court reasoned that the doctrine of equivalents could not apply in this type of binary situation. That lead to the court’s conclusion that allowing equivalents for continuous operation would vitiate the intermittent operation limitation. On appeal, Steuben contends the court ignored precedent against using a ‘binary choice’ approach to vitiation. See, Deere & Co. v. Bush Hog, LLC, 703 F.3d 1349, 1356–57 (Fed. Cir. 2012) (“Courts should be cautious not to shortcut this inquiry by identifying a ‘binary’ choice in which an element is either present or ‘not present.'”). The patentee also argues that substantial evidence supported the jury’s equivalents verdict based on applying the proper function-way-result test.

This aspect of the dispute thus raises important questions about how narrowly the doctrine of equivalents should be applied. And, in addition, it challenges the power distribution between judge and jury in finding infringement.

Reverse Doctrine of Equivalents

A more surprising aspect of Judge Connolly’s decision is his application of the reverse doctrine of equivalents. Reverse DOE allows an accused infringer to escape liability, even if its product or process literally satisfies every element of the patent claim, if the accused product or process is so substantially changed in principle that it performs the same or a similar function in a substantially different way. The doctrine originated in Supreme Court precedent such as Graver Tank and was designed to prevent unwarranted extension of patent scope over later-developed technologies functioning in new ways. However, the doctrine is controversial because it negates what would otherwise constitute infringement under the statute, conflicts with literal claim interpretation, and is seldom applied by courts today.

For the ‘591 patent, the lower court rejected the jury verdict of infringement based upon the reverse DOE — holding that the accused product operated “in a substantially different way” from Steuben’s invention as described in its specification. Here, the claims required a “second sterile location.” Steuben accomplished this with a redesign of filling valves to avoid attracting contaminants and use of sterilant. On the other hand, the accused product used a bellows surrounding the valve stem to prevent contamination.

The district court found the accused product’s approach to fit within the literal claim scope, but still non infringing because the approach was radically different from that described in Steuben’s specification.

In the case, Shibuya provided expert testimony of the key differences of operation by comparing the accused product against the disclosed embodiments. During the trial, the patentee focused on the claim language and did not attempt to rebut the argument that the underlying approaches to create the sterile region was quite different. (Steuben also apparently mischaracterized the patents disclosure). In its JMOL decision, the court concluded that the unrebutted evidence of significant difference was enough to entitle Shibuya to JMOL of noninfringement under the reverse doctrine of equivalents. The court emphasized here that the critical issue is whether the accused device is so far changed in principle that it operates substantially differently from the claim, even if it literally infringes.

On appeal, Steuben argues the court fundamentally misapplied Reverse DOE analysis by comparing Shibuya’s device to patent specifications rather than the actual claims. It also contends the Reverse DOE improperly negates infringement, conflicting with the Patent Act.

The Federal Circuit now has the opportunity (and duty) to shape the law on these two important equivalents doctrines. On the doctrine of equivalents, the court can provide guidance on applying a legal test of vitiation versus the factually intensive function-way-result test. In the lead up to the recent Amgen decision, many of us have had ongoing discussions about the relationship between disclosure doctrines (enablement/WD) and the doctrine of equivalents. As one doctrine is locked-down, there is more pressure to expand the other. With so much focus on the disclosure side, it may be time to ease up on the DOE limitations.

For the reverse doctrine of equivalents, the court can clarify if this much maligned doctrine still remains viable in today’s statutory framework. And if so, the court should delineate the proper role of the reverse doctrine versus literal claim interpretation. As with DOE, I would argue that reverse DOE should be given to the jury to decide rather than JMOL.

The appeal was filed by Cook Alciati (Steuben’s former Chief IP Counsel, now in private practice at Gardella Grace). A team from Sterne Kessler, apparently led by appellate specialist JC Rozendaal represents the defendant-appellee.

Law Professor at the University of Missouri School of Law. View all posts by Dennis Crouch →