IP Law Daily, PATENT—Fed. Cir.: ITC’s no-violation determination affirmed in marine air conditioning systems patent dispute, (Apr 7, 2026)

By Ravindra Kumar Singh, B.L.

ITC correctly construed the patent claims; its findings on anticipation, noninfringement, and domestic industry were supported by substantial evidence.

In a non-precedential disposition, the U.S. Court of Appeals for the Federal Circuit affirmed the U.S. International Trade Commission’s final determination denying relief to Dometic Corp. and Dometic Sweden AB in a Section 337 investigation involving U.S. Patent No. 8,056,351 (the ’351 patent). The court held that claims 1–2, 4–5, and 7 were invalid as anticipated by prior art, and that claims 18–22 were not infringed and failed to meet the domestic industry requirement. The court concluded that the Commission correctly construed the disputed claim terms and that its findings were supported by substantial evidence (Dometic Corp. v. ITC, No. 24-1796 (Fed. Cir. Apr. 6, 2026)).

Background. The appellants, Dometic Corp. and Dometic Sweden AB, are manufacturers of marine and mobile climate control systems and related equipment. The appellee, the U.S. International Trade Commission (ITC), is the federal agency responsible for adjudicating trade-related patent disputes under Section 337 of the Tariff Act of 1930. The intervenors—Citimarine, L.L.C., Mabru Power Systems, Inc., Shanghai Hopewell Industrial Co., Ltd., and Shanghai Hehe Industrial Co., Ltd.—are companies engaged in the manufacture, supply, and distribution of marine air conditioning systems and related components.

The ’351 patent, titled Air Conditioning Device for a Nautical Vehicle, discloses a compact marine air conditioning system comprising a main body, a blower, and an assembly that enables adjustment of airflow direction through rotational mechanisms. The asserted claims include independent claims 1 and 18, which recite configurations involving one or more axes of rotation to alter the orientation of the blower outlet in confined installation environments.

Dometic filed a complaint before the ITC in November 2022, alleging that the intervenors imported and sold marine air conditioning systems that infringed the ’351 patent in violation of Section 337. The Commission instituted Investigation No. 337-TA-1346 in December 2022. Following claim construction and summary determination proceedings, the administrative law judge found that prior art—specifically a product known as the “Vector Compact”—anticipated claims 1–2, 4–5, and 7. The ALJ later issued a final initial determination concluding that the accused products did not infringe claims 18–22 and that Dometic failed to satisfy the technical prong of the domestic industry requirement. The Commission affirmed both determinations in March 2024. Dometic appealed, challenging the anticipation ruling and the claim constructions underlying the noninfringement and domestic industry findings.

Claim construction framework. The Federal Circuit reviewed the Commission’s determinations under the Administrative Procedure Act, applying de novo review to legal issues and substantial evidence review to factual findings. The court reiterated that claim construction depends primarily on intrinsic evidence and addressed the presumption articulated in Becton, Dickinson & Co. v. Tyco Healthcare Group, LP, 616 F.3d 1249 (Fed. Cir. 2010), that separately listed claim elements are presumed distinct. The court emphasized that this presumption is rebuttable and must be evaluated in the context of the patent as a whole.

Anticipation. The court rejected Dometic’s argument that the claimed “assembly” must be physically separate from the “main body,” which would have precluded a finding of anticipation. It held that the intrinsic evidence, including the specification and abstract, demonstrated that components of the assembly, such as the “guiding cover,” could be integrated into the main body.

Distinguishing Becton, the court noted that no claim language rendered such an interpretation illogical or inconsistent. It further relied on the patent’s figures and description, which showed that the guiding cover could be mounted above components forming part of the main body. Accordingly, the court affirmed the Commission’s finding that the prior art Vector Compact disclosed the “guiding cover” limitation and anticipated claims 1–2, 4–5, and 7.

Noninfringement. Addressing claim 18, the court upheld the Commission’s construction requiring two distinct rotational axes. It concluded that the claim language explicitly recited separate rotational functions—one involving rotation of the blower and another involving rotation of the duct element within the assembly.

The specification supported this interpretation by describing a system that enables flexible orientation of the blower outlet through independent rotational mechanisms, facilitating installation in confined marine environments. The court rejected Dometic’s argument that a single rotational mechanism could satisfy both limitations, explaining that the claimed invention required two structurally and functionally distinct modes of rotation.

The prosecution history reinforced this conclusion. During examination, Dometic amended the claims to introduce separate “first” and “second” axes, thereby distinguishing the invention from prior art. The court held that adopting Dometic’s proposed construction would improperly collapse these limitations and negate the effect of the amendment.

Because the accused products lacked the required dual-axis configuration, the court affirmed the Commission’s finding of noninfringement. For the same reasons, Dometic failed to establish that its domestic products practiced the asserted claims, defeating the technical prong of the domestic industry requirement.

Conclusion. Thus, the Federal Circuit affirmed the Commission’s determination in full, holding that the anticipation, noninfringement, and domestic industry findings were legally sound and supported by substantial evidence. The court directed that each party bear its own costs.

The Case is No. 24-1796.

Judge: Taranto, R.

Attorneys: Stephen Reid Howe (Husch Blackwell LLP) for Dometic Corp. Namo Kim, U.S. International Trade Commission, for International Trade Commission.

Companies: Dometic Corp.

Cases: Patent FedCirNews