In a stunning blow to Apple Inc., a federal jury in California has ordered the tech giant to pay medical device maker Masimo Corp. $634 million for infringing on a patent related to blood-oxygen monitoring technology in the Apple Watch. The verdict, delivered on November 15, 2025, marks a significant escalation in the long-simmering legal battle between the two companies, which has already led to import bans and feature disables in the U.S. market.

The case centered on Masimo’s allegations that Apple’s smartwatch features, including workout modes and heart-rate notifications, violated its intellectual property for low-power pulse oximetry. According to court documents, the infringement affected millions of Apple Watch units sold since the feature’s introduction in the Series 6 model in 2020.

The Roots of the Rivalry

The dispute traces back to 2013, when Apple reportedly approached Masimo about potential collaboration on health-monitoring tech, only to allegedly poach key engineers and incorporate similar features into its watches. Masimo filed suit in 2020, claiming theft of trade secrets and patent infringement, as reported by Reuters.

A prior ruling by the U.S. International Trade Commission in 2023 led to a temporary import ban on Apple Watches with blood-oxygen sensing, forcing Apple to disable the feature in U.S. models starting in January 2024. Apple appealed that decision, and the ban was lifted pending further review, but the latest jury verdict revives the pressure.

Jury’s Damning Decision

The eight-day trial in the U.S. District Court for the Central District of California focused on one specific Masimo patent, which expired in 2022, covering optical sensors for detecting blood flow during activities. Jurors found that Apple Watch’s workout mode and heart-rate alerts infringed on this technology, awarding damages based on royalties for over 10 million affected units, per details from AppleInsider.

Masimo hailed the outcome as a victory for innovation. “We are pleased by this outcome, and appreciate the time and attention given to our case by the court and the jury,” the company stated in a press release, as quoted by MacRumors.

Apple’s Appeal Strategy

Apple, undeterred, announced plans to appeal immediately. A spokesperson told TechCrunch, “We disagree with the verdict and will appeal,” emphasizing that the patent in question had already expired and that many of Masimo’s other claims were deemed invalid in prior proceedings.

The appeal could drag on for years, potentially reaching the U.S. Court of Appeals for the Federal Circuit. Industry analysts suggest Apple might seek to invalidate the patent entirely or argue for reduced damages, drawing parallels to its successful navigation of past IP disputes.

Broader Implications for Wearables

Beyond the courtroom, the verdict could reshape the wearable tech landscape. With Apple controlling over 50% of the global smartwatch market, any disruption to features like blood-oxygen monitoring—crucial for fitness tracking and health alerts—might push competitors like Samsung and Fitbit to accelerate their own innovations, according to insights from 9to5Mac.

Posts on X (formerly Twitter) reflect mixed sentiment: some users praise Masimo for standing up to Big Tech, while others worry about higher prices for consumers if Apple passes on the costs. One X post from tech account Techmeme highlighted the $634 million figure as a record in wearable patent cases.

Financial Fallout and Market Reactions

For Apple, the $634 million hit represents a fraction of its $94 billion quarterly revenue, but it adds to mounting legal expenses. Shares dipped 1.2% in after-hours trading following the verdict, as noted by Yahoo Finance.

Masimo, meanwhile, saw its stock surge 15% on the news, boosting its market cap to over $5 billion. The company, known for hospital-grade pulse oximeters, has leveraged the dispute to expand into consumer wearables, launching its own Freedom smartwatch in 2024.

History of Health Tech Clashes

This isn’t Apple’s first rodeo in health-tech patents. In 2024, a separate jury awarded Apple a symbolic $250 against Masimo for design patent infringements on watch bands, a far cry from the current damages. Bloomberg Law reported that Masimo plans to use the new funds to fuel R&D in non-invasive monitoring tech.

The feud has also drawn regulatory scrutiny. The U.S. Patent and Trademark Office invalidated several Masimo patents in 2024 at Apple’s request, but the surviving one proved pivotal in this trial.

Potential Product Pivots

Looking ahead, Apple may redesign future Apple Watch models to sidestep Masimo’s IP, possibly integrating alternative sensors or software algorithms. Insiders speculate this could delay the rollout of advanced health features in the upcoming Series 11, based on leaks shared on X by MacRumors.

Consumers in the U.S. have already felt the impact: since early 2024, new Apple Watches sold domestically lack active blood-oxygen tracking, though users can enable it via software hacks, as discussed in forums and reported by Digital Trends.

Industry-Wide Ripple Effects

The case underscores the high stakes of health data in wearables, where patents on biometric sensors are fiercely contested. Experts from Wareable warn that similar disputes could arise with AI-driven health insights, potentially stifling innovation if litigation becomes the norm.

For Masimo, the win validates its aggressive IP defense strategy. CEO Joe Kiani has publicly accused Apple of systemic poaching, telling Reuters in 2023, “They took our people, they took our technology.” Apple denies these claims, maintaining all developments were independent.

Legal and Ethical Dimensions

Ethically, the battle raises questions about tech giants’ dominance in health innovation. Advocacy groups argue that verdicts like this level the playing field for smaller innovators, per analysis in The Daily Journal.

As the appeal looms, both companies continue to invest heavily in wearables. Apple recently teased enhanced heart monitoring in watchOS 12, while Masimo pushes boundaries with FDA-cleared continuous monitoring devices.

Future of the Fight

With parallel lawsuits ongoing, including Masimo’s claims against Apple’s newer models, the saga is far from over. A potential settlement remains on the table, though Apple CEO Tim Cook stated in 2024 that the company prefers appeals over payouts, as reported by 9to5Mac.

Ultimately, this verdict could redefine how tech firms approach partnerships and IP in the booming $50 billion wearables market, forcing a reevaluation of collaboration versus competition.