The Federal Circuit’s decision in Apple Inc. v. International Trade Commission , Case No. 2024-1285 (Fed. Cir., Mar. 19, 2026), delivers a clear and practical message: a domestic industry under Section 337 does not require a finished commercial product. Iterative prototypes—supported by testing, engineering records, and witness testimony—can be enough.
That holding represents a meaningful clarification of how the domestic industry requirement operates in modern technology development, where products often evolve through multiple pre-commercial iterations. The court’s approach reflects a broader trend toward accommodating research-and-development-stage technologies within the ITC framework.
At a high level, the Federal Circuit affirmed the Commission’s determination that Apple violated Section 337 by importing Apple Watches that infringed Masimo’s pulse oximetry patents, and upheld the resulting limited exclusion order. But the most consequential aspects of the opinion lie in its treatment of domestic industry and, to a lesser extent, prosecution laches.
Background: The Dispute Over Wearable Blood Oxygen Technology
Masimo’s asserted patents cover wearable devices that measure blood oxygen using optical emitters and photodetectors. These systems rely on light transmitted into tissue and measured upon return to calculate oxygen saturation.
Following Apple’s introduction of blood oxygen functionality in the Apple Watch Series 6, Masimo filed a Section 337 complaint at the ITC. The Commission found infringement and issued a limited exclusion order barring importation of infringing Apple Watches.
On appeal, Apple challenged nearly every aspect of the Commission’s ruling, with its most substantial arguments directed at the domestic industry requirement.
Domestic Industry: A Less Rigid Framework
To establish a violation of Section 337, a complainant must show both infringement and the existence of a domestic industry relating to the patented article. The domestic industry requirement includes:
- A technical prong, requiring a patent-practicing article; and
- An economic prong, requiring significant domestic investment in that article.
Apple’s central argument was that Masimo failed both prongs because it did not identify a sufficiently concrete, finished product.
The Federal Circuit rejected that argument and, in doing so, clarified several important aspects of the doctrine.
Technical Prong: Representative Articles and Iterative Prototypes
The court confirmed that a complainant is not required to identify a single, finalized product in its complaint. Instead, it may identify a representative article, and the Commission may rely on the full evidentiary record developed during the investigation.
Here, Masimo identified a “Masimo Watch” and supported that identification with CAD renderings, prototype devices, and testimony describing an iterative design process. The Commission treated those prototypes as embodiments of a single domestic industry article.
Critically, the court rejected three related limitations urged by Apple:
- The analysis is not confined to the exact article depicted in the complaint.
- It is not limited to the specific physical units produced in discovery.
- It does not require direct evidence of a patent-practicing product.
Instead, prototype devices developed through a continuous design process can collectively establish the existence of a patent-practicing article at the time of the complaint.
Charles Gideon Korrell notes that this clarification is particularly significant for hardware and device companies, where early-stage prototypes often differ materially from eventual commercial products. The decision reduces the risk that timing—rather than substance—will determine whether a domestic industry exists.
Circumstantial Evidence Is Sufficient
The court also rejected the notion that only direct evidence can establish the existence of a domestic industry article.
The Commission relied on:
- Pre-complaint testing of prototype devices
- Witness testimony describing device functionality
- Engineering records documenting development
The Federal Circuit held that this type of circumstantial evidence is fully acceptable. There is no heightened evidentiary requirement in Section 337 proceedings that would preclude reliance on inference and corroborated testimony.
Charles Gideon Korrell observes that this aspect of the decision reinforces the evidentiary flexibility of ITC proceedings and aligns them with broader principles of proof. For companies developing complex technologies, this reduces the burden of preserving and producing perfect physical artifacts.
Economic Prong: Investments in Predecessor Prototypes Count
Apple also challenged the Commission’s reliance on Masimo’s investments in earlier prototype devices that did not themselves practice the asserted claims.
The court affirmed the Commission’s approach, holding that investments in non-practicing prototypes may count toward the economic prong when they are sufficiently tied to the patented article.
The key inquiry is whether there is a nexus between the earlier investments and the eventual patent-practicing device. Where earlier prototypes contribute to the development of features incorporated into the patented article, those investments may be considered “with respect to” that article.
The court relied on precedents such as Motorola Mobility v. ITC and Microsoft v. ITC, which recognize that investments directed to significant components or development efforts can satisfy the statute.
Charles Gideon Korrell believes this is one of the most practically important aspects of the decision. It confirms that companies can aggregate R&D investments across multiple development stages, provided those efforts are part of a continuous and technically connected process.
Practical Implications for ITC Complainants
The decision provides several clear takeaways for parties considering Section 337 actions:
- A complaint may identify a representative product, not a finalized commercial embodiment.
- Prototype iterations can collectively satisfy the technical prong.
- Circumstantial evidence, including testing and testimony, is sufficient to prove the existence of a patent-practicing article.
- Investments in predecessor technologies may count toward the economic prong if they are tied to the patented article.
These principles lower the evidentiary barrier for companies that are still in the development phase and have not yet commercialized a finished product.
Claim Construction and Infringement
Apple’s infringement arguments depended on narrow claim constructions, particularly for terms like “over,” “above,” and “openings.”
The court adopted a functional interpretation, concluding that these terms describe the relationship between components within the device, rather than their orientation relative to gravity or empty space. It also confirmed that “openings” may include transparent material.
With those constructions in place, the court affirmed the Commission’s infringement findings.
Written Description: Combining Disclosures Across Embodiments
Apple argued that the asserted claims lacked adequate written description because they combined features drawn from multiple embodiments.
The court disagreed, finding that the specification supported such combinations and that a skilled artisan would understand the disclosures as conveying possession of the claimed invention.
This holding reinforces the principle that written description does not require a single embodiment that mirrors the claims, so long as the specification reasonably conveys the claimed subject matter.
Obviousness: Generalized Disclosures Are Not Enough
Apple’s obviousness case relied on prior art that disclosed measuring physiological parameters generally.
The Commission—and the Federal Circuit—found that insufficient. The prior art did not disclose measuring blood oxygen saturation specifically, nor did it provide guidance on how to do so.
That gap was fatal to the obviousness defense. The decision underscores that prior art must address the specific claimed functionality, not merely adjacent concepts.
Prosecution Laches: A High Bar Remains
Apple’s prosecution laches argument focused on the time gap between Masimo’s early priority filings and the later applications that issued as the asserted patents.
The court rejected this argument, emphasizing that:
- Continuous prosecution activity defeats claims of unreasonable delay
- Laches requires egregious misuse of the patent system
- Speculation about intent to target a competitor’s product is insufficient
At the same time, the decision suggests that a different outcome might be possible where there is concrete evidence that claims were deliberately delayed and tailored to cover a competitor’s product.
Charles Gideon Korrell notes that prosecution laches remains a difficult defense to sustain, but this case illustrates the type of evidentiary showing that would be required to make it viable.
Conclusion
The Federal Circuit’s decision in Apple v. ITC reflects a pragmatic approach to Section 337 that aligns with modern product development realities. By allowing complainants to rely on iterative prototypes, circumstantial evidence, and development-stage investments, the court has clarified that domestic industry is not limited to finished, commercialized products.
For companies developing complex technologies, the message is clear: a well-documented development process—rather than a completed product—can be enough.