This article conducts an in-depth analysis of the patent infringement lawsuit between Apple Inc. and the medical technology company Masimo. The core disputes of the case center on whether the health features of Apple's Apple Watch infringe Masimo's '776 patent, whether the Apple Watch qualifies as a patient monitor, and the calculation of the damages amount. The article systematically reviews the background of the case, the court ruling, specific details of the disputes, and the impact of the case, while proposing insights for Chinese enterprises and practitioners from an intellectual property perspective.

I. Case Background and Core Disputes

(A) Case Background As a world-renowned consumer electronics giant, Apple Inc. has continuously integrated health features, such as heart rate monitoring and blood oxygen detection, into its Apple Watch product lines to enhance product market competitiveness. Masimo, on the other hand, is a specialized company that has been deeply rooted in the field of medical monitoring technology for many years, possessing numerous core technologies and patents in pulse oximetry monitoring. The two parties engaged in a fierce conflict over patent issues, with the focus converging on one of Masimo’s core patents—the '776 patent.

(B) Core Disputes

1.  Dispute over Product Attributes: Masimo asserted that features such as high/low heart rate notifications on Apple's Apple Watch are inherently patient monitors in nature, and their manner of operation infringes the '776 patent. Apple, however, firmly maintained that the Apple Watch is a consumer electronics product whose health features provide reliable information when conditions permit, and its original design intent and performance standards are fundamentally distinct from professional patient monitors in hospitals that require "never missing a critical medical event." This lawsuit virtually evolved during the trial into a battle over the definition of whether the Apple Watch is a patient monitor.

2.  Dispute over Damages Amount: The parties also held vast disagreements regarding the calculation of the damages amount. Masimo's damages expert proposed that if the two parties had initially engaged in a hypothetical license negotiation, a reasonable patent royalty rate should be in the magnitude of $634 million, a figure that accounted for the massive sales volume of the Apple Watch and the value contributed by the involved patent technology therein. Apple, conversely, fiercely opposed this, arguing that Masimo’s claim amount was entirely unrealistic and that even if infringement existed, only a nominal damage payment should be made at most, because Masimo could not prove that its patented technology made such a monumental contribution to the sales of the Apple Watch.

II. Court Ruling

(A) Adjudicating Body and Time The U.S. District Court for the Central District of California rendered its ruling on this case on November 14, 2025.

(B) Adjudication Result The jury determined that Apple infringed Masimo’s '776 patent and ruled that Apple must pay Masimo up to $634 million (approximately RMB 4.5 billion) in damages. This adjudication result was astonishing, representing not only an affirmation of Masimo’s years of persistence but also dropping a bombshell onto the global technology and intellectual property communities.

III. Analysis of Dispute Details

(A) Basis of Masimo's Claims As a specialized company in the field of medical monitoring technology, Masimo considers its '776 patent to be one of its core assets. The company argued that the health features of Apple's Apple Watch are highly similar to the functions of a patient monitor, thereby infringing its patent rights and interests. From a technical perspective, pulse oximetry monitoring is an important function of a patient monitor, and features such as blood oxygen detection on the Apple Watch may involve similar technical principles. Masimo pursued its patent rights and interests through legal channels, aiming to protect its leading position and commercial interests in the medical technology market.

(B) Apple's Grounds for Defense Apple emphasized that the Apple Watch is a consumer electronics product whose target users are ordinary consumers, primarily providing convenient features for health monitoring, which fundamentally differs from professional patient monitors in performance standards, usage scenarios, and original design intent. Professional patient monitors must satisfy extremely high requirements for accuracy and reliability in medical premises such as hospitals, where no critical medical event can be missed. The health features of the Apple Watch merely provide information when conditions permit and cannot substitute for professional medical equipment. Apple's defense aimed to demonstrate that its product did not infringe Masimo's patent, thereby avoiding the payment of high damages.

(C) Damages Calculation Logic The jury ultimately adopted the damages calculation logic proposed by Masimo’s side, determining that a reasonable patent royalty rate was in the magnitude of $634 million. This calculation took multiple factors into account, first of which was the massive sales volume of the Apple Watch. As a globally best-selling smartwatch, the Apple Watch commands a highly substantial market share and sales quantity, and the involved patent technology may have played an important role therein. Secondly, the value of the involved patent technology to the health monitoring features of the Apple Watch cannot be ignored. If Apple were to utilize the patented technology legally, it would need to pay corresponding licensing fees. Therefore, the jury deemed the damages amount of $634 million to be reasonable.

IV. Impact of the Case

(A) Significance for Masimo

1.  Financial Compensation: Masimo obtained damages as high as $634 million, which represents a massive financial compensation for the company, assisting it in further conducting research and development as well as market expansion.

2.  Public Opinion and Moral Support: This victory provided powerful support in public opinion and morality for Masimo's image as a victim. Masimo has consistently accused Apple not only of infringing its patents but also of poaching multiple key employees, including its Chief Medical Officer, under the guise of collaboration in 2013 to access its core technology, subsequently misappropriating its trade secrets. Although this judgment primarily targeted patent infringement, support in public opinion and morality helps Masimo occupy a more advantageous position in future market competition.

3.  Impact on ITC Investigation Proceedings: This victory will tremendously impact the subsequent proceedings of the ongoing Section 337 investigation by the ITC (U.S. International Trade Commission). As early as October 2023, the ITC had ruled that the Apple Watch infringed Masimo’s patents and issued a limited exclusion order. Apple implemented workaround designs through software updates and other methods. Now, armed with this astronomical infringement judgment from the federal court, Masimo can use it as the most powerful evidence to request the ITC to strengthen its enforcement proceedings to block the sales of new versions of Apple's watches in the United States. Holding both the federal court infringement judgment and the ITC exclusion order, Masimo will command absolute initiative in any potential future settlement negotiations with Apple.

(B) Impact on Apple

1.  Financial Loss: Apple needs to pay damages up to $634 million, which will exert a certain impact on its financial condition.

2.  Appeal and Maneuvering: Apple is highly likely to file an appeal, attempting to overturn the judgment or reduce the damages amount. Meanwhile, the maneuvering between the two parties at the ITC will also continue, and Apple may adopt more measures to counter the ITC exclusion order and Masimo's litigation pressure.

3.  Product Adjustment: To avoid further infringement disputes, Apple may adjust the health features of its Apple Watch or seek alternative technical solutions.

(C) Insights for Chinese Enterprises and Practitioners

1.  Emphasize Patent Quality: Masimo's ability to contend with a giant like Apple in this protracted war relied not on piling up a quantity of patents, but on a few high-quality core patents that were meticulously polished, highly stable in rights, and tightly bound to core product features. When conducting overseas patent portfolios, Chinese enterprises must shift their mindset away from valuing quantity over quality, and concentrate resources on polishing core patents that can truly bottleneck competitors.

2.  Opportunities for Small Companies: This victory shattered the stereotype held by many that small companies are inevitably the losers in patent wars. In a legal system that respects rules, patent rights are the most powerful weapon granted to innovators to challenge market monopolists. Chinese "Specialized, Refined, Differential, and Innovational" (SRDI) enterprises should dare to and be adept at utilizing IP weapons to protect themselves and challenge unfair competition.

3.  Establish a Three-Dimensional Protection System: Masimo's litigation strategy was not limited to patent infringement; it was consistently accompanied by allegations of Apple misappropriating trade secrets and poaching core employees. This combined-punch approach played an inestimable role in winning jury sympathy, shaping public opinion, and exerting moral pressure on the opposing party. When providing IP strategic consulting to clients, Chinese practitioners must not limit themselves merely to patent applications; they must help clients establish a three-dimensional protection system, incorporating patents, trade secrets, copyrights, trademarks, and even employee confidentiality agreements and non-compete agreements into the overall strategic considerations.

Conclusion

The patent infringement case between Apple and Masimo is an intellectual property dispute of major influence. The core disputes of the case unfolded around the definition of product attributes and the calculation of the damages amount, and the court's adjudication results have generated profound impacts on both parties. For Masimo, this is a major victory, which not only secured financial compensation but also gained an advantageous position in public opinion and market competition. For Apple, it faces challenges such as financial losses, appellate pressure, and product adjustments. This case also provides valuable insights for Chinese enterprises and practitioners, emphasizing the importance of patent quality, opportunities for small companies, and the establishment of a three-dimensional protection system. In future intellectual property competition, enterprises and practitioners need to attach greater importance to patent strategies and utilize legal weapons to safeguard their legitimate rights and interests.