Masimo shares jump 34% after Danaher agrees to buy the company for $180 per share in cash

Masimo Corporation (MASI) is up 34.08% today. Here is some analysis on what might have caused this price movement.

Analysis: The stock surged after Masimo agreed to be acquired by Danaher in an all-cash deal, giving investors a clear, near-term valuation anchor. The move largely reflects the gap between Masimo’s prior close and the $180-per-share offer price, adjusted for deal-completion risk and timing.

Details:

Danaher agreed to acquire Masimo for $180 per share in cash, valuing the transaction at roughly $10 billion and implying a sizable premium to the prior closing price.

Masimo is expected to operate as a standalone business within Danaher’s Diagnostics segment after the transaction closes.

The deal is anticipated to close in the second half of 2026, subject to customary conditions and regulatory approvals.

This price action is consistent with typical merger-arbitrage dynamics, with MASI trading below the offer price to reflect uncertainty and time value until closing.

Sources:

Financial Times

The Wall Street Journal

Barron's

Disclaimer: This price movement analysis was generated with the help of AI. Please double-check the information provided for mistakes.

$MASI Insider Trading Activity

$MASI insiders have traded $MASI stock on the open market 3 times in the past 6 months. Of those trades, 0 have been purchases and 3 have been sales.

Here’s a breakdown of recent trading of $MASI stock by insiders over the last 6 months:

ANAND SAMPATH (EVP, Ops & Clinical Research) has made 0 purchases and 3 sales selling 18,680 shares for an estimated $2,555,570.

To track insider transactions, check out Quiver Quantitative's insider trading dashboard.

$MASI Hedge Fund Activity

We have seen 169 institutional investors add shares of $MASI stock to their portfolio, and 220 decrease their positions in their most recent quarter.

Here are some of the largest recent moves:

BLACKROCK, INC. removed 1,505,472 shares (-14.5%) from their portfolio in Q4 2025, for an estimated $195,801,688
HOLOCENE ADVISORS, LP removed 1,243,607 shares (-100.0%) from their portfolio in Q3 2025, for an estimated $183,494,212
CAPITAL RESEARCH GLOBAL INVESTORS removed 1,216,234 shares (-65.6%) from their portfolio in Q4 2025, for an estimated $158,183,394
ALLIANCEBERNSTEIN L.P. removed 790,506 shares (-93.7%) from their portfolio in Q3 2025, for an estimated $116,639,160
DURABLE CAPITAL PARTNERS LP removed 543,279 shares (-46.7%) from their portfolio in Q3 2025, for an estimated $80,160,816
VANGUARD GROUP INC removed 461,225 shares (-9.6%) from their portfolio in Q4 2025, for an estimated $59,986,923
UBS GROUP AG added 429,474 shares (+252.9%) to their portfolio in Q4 2025, for an estimated $55,857,388

To track hedge funds' stock portfolios, check out Quiver Quantitative's institutional holdings dashboard.

$MASI Government Contracts

We have seen $1,115,500 of award payments to $MASI over the last year.

Here are some of the awards which we have have seen pay out the most over the last year:

MASIMO ROOT PLATFORM SYSTEM: $130,396
4568591237!MIGHTYSAT, OXIMETER, RX,1/BX,US: $54,280
4567819755!CAPNOMETER EMMA 1S: $51,600
4568325430!CAPNOMETER EMMA 1S: $46,800
4567385447!CAPNOMETER EMMA 1S: $43,200

To track government contracts to publicy traded companies, check out Quiver Quantitative's government contracts dashboard.

$MASI Congressional Stock Trading

Members of Congress have traded $MASI stock 1 times in the past 6 months. Of those trades, 0 have been purchases and 1 have been sales.

Here’s a breakdown of recent trading of $MASI stock by members of Congress over the last 6 months:

REPRESENTATIVE KEVIN HERN sold up to $50,000 on 09/26.

To track congressional stock trading, check out Quiver Quantitative's congressional trading dashboard.

$MASI Analyst Ratings

Wall Street analysts have issued reports on $MASI in the last several months. We have seen 1 firms issue buy ratings on the stock, and 0 firms issue sell ratings.

Here are some recent analyst ratings:

BTIG issued a "Buy" rating on 12/04/2025

To track analyst ratings and price targets for $MASI, check out Quiver Quantitative's $MASI forecast page.

$MASI Price Targets

Multiple analysts have issued price targets for $MASI recently. We have seen 3 analysts offer price targets for $MASI in the last 6 months, with a median target of $187.0.

Here are some recent targets:

Marie Thibault from BTIG set a target price of $200.0 on 12/04/2025
Travis Steed from B of A Securities set a target price of $162.0 on 11/17/2025
Vik Chopra from Wells Fargo set a target price of $187.0 on 11/05/2025

This article is not financial advice. See Quiver Quantitative's disclaimers for more information. Note that there may be inaccuracies due to mistakes in ticker-mapping, and other anomalies.