Masimo's 0.11% Stock Gain Amid 26.58% Volume Drop and Legal Uncertainty Leaves It Ranking 404th in Market Activity

Market Snapshot

Masimo (MASI) closed on March 23, 2026, with a 0.11% gain, despite a 26.58% decline in trading volume to $310 million, ranking 404th in market activity. The muted volume decline and modest price increase suggest mixed investor sentiment, potentially reflecting uncertainty around ongoing legal developments involving the company’s blood-oxygen monitoring patents.

Key Drivers

A preliminary ruling by the U.S. International Trade Commission (ITC) on March 19, 2026, marked a pivotal development for Masimo. Administrative Law Judge Monica Bhattacharyya concluded that Apple’s redesigned Apple Watch models do not infringe on Masimo’s patents related to light-based pulse oximetry. This decision, published on March 19, effectively halted a renewed import ban on the smartwatches, granting Apple a legal reprieve in a protracted dispute. The ruling focused on Apple’s “Redesign 2 Watch” and determined that the company neither directly infringed Masimo’s patents (U.S. Patent Nos. 10,912,502 and 10,945,648) nor induced infringement when the device is paired with an iPhone.

However, the preliminary nature of the ITC’s decision introduces lingering uncertainty. The full ITC commission must review and affirm the judge’s findings, a process expected to take months. This procedural gap leaves Masimo’s legal position partially unresolved, as the company could still face challenges if the commission reverses the ruling. The outcome also hinges on whether Apple’s redesign truly circumvents the patents, as legal analysts have debated the technical nuances of the workaround.

Compounding the complexity, the U.S. Court of Appeals for the Federal Circuit on the same day affirmed the ITC’s 2023 ruling that Apple’s unmodified Apple Watch models infringed Masimo’s patents. This dual-layered legal landscape—where the redesigned models are cleared but the original infringement remains validated—highlights the multifaceted risks for Masimo. While the preliminary ruling shields Apple from immediate disruptions, the Federal Circuit’s affirmation reinforces the validity of Masimo’s intellectual property claims, potentially enabling the company to pursue further remedies if the redesigned technology is found to still infringe.

Apple’s strategic response to the 2023 import ban further complicates the analysis. The tech giant disabled the blood-oxygen feature in affected models before reintroducing an updated version in August 2025, following approval from U.S. Customs and Border Protection. Masimo has contested this workaround, arguing it circumvents the original legal constraints. The ITC judge’s March 19 ruling appears to validate Apple’s redesign, but the company’s ability to innovate around patent protections could diminish Masimo’s leverage in future disputes.

For investors, the interplay of these factors creates a delicate balance. The preliminary ITC ruling likely alleviated short-term concerns about supply chain disruptions for Apple’s wearable devices, which could indirectly benefit Masimo by maintaining market stability. However, the unresolved legal challenges and the Federal Circuit’s reaffirmation of prior infringement findings underscore the long-term risks for Masimo. The stock’s modest 0.11% gain may reflect cautious optimism that the redesigned Apple Watch poses limited immediate threats, but the 26.58% drop in trading volume suggests investor hesitancy to commit capital amid unresolved litigation.

The broader implications for Masimo’s business model remain significant. As a medical technology firm with a core focus on pulse oximetry, the company’s ability to enforce its patents against a market leader like Apple could influence its competitive positioning. If the ITC ultimately affirms the judge’s findings, Masimo may face reduced revenue opportunities from licensing or settlements. Conversely, a reversal in the commission’s review could reignite pressure on Apple to negotiate terms, potentially benefiting Masimo’s financial prospects. The outcome of the full ITC review, therefore, will be critical in shaping both the company’s legal strategy and its stock performance in the coming months.