Danaher Closes $9.9 Billion Masimo Takeover, Ending Its Nasdaq Listing

Danaher has completed its acquisition of Masimo, the patient monitoring company best known for pulse oximetry, Danaher said in a release on June 10. Masimo is now a wholly owned subsidiary of Danaher, and its common stock has ceased trading on the Nasdaq Stock Market.

The deal was valued at $9.9 billion, the Orange County Business Journal reported on the day of the closing. Under the merger agreement dated February 16, 2026, each outstanding Masimo share was cancelled and converted into the right to receive $180.00 in cash, without interest, according to a Form 8-K that Masimo filed with the Securities and Exchange Commission. The filing said Masimo also paid off all obligations under its credit agreement on the closing date.

A stand-alone unit within Diagnostics

Danaher said Masimo will continue to operate under the Masimo brand as a stand-alone operating company within its Diagnostics segment. Irvine, California-based Masimo specializes in non-invasive patient monitoring devices, the Business Journal said.

"Masimo is a strong strategic fit for Danaher. Together, we expect to strengthen our ability to deliver differentiated products in acute care settings and accelerate Masimo's growth and global reach," said Julie Sawyer Montgomery, Danaher's executive vice president of Diagnostics.

When the deal was announced in February, Healthcare Dive reported that both companies' boards had unanimously approved the $180-per-share cash transaction and that Masimo would join Radiometer, Leica Biosystems, Cepheid and Beckman Coulter Diagnostics under the Danaher umbrella. At the time, Danaher said Masimo was expected to contribute high-single-digit core revenue growth over the long term and projected Masimo's earnings before interest, tax, depreciation and amortization at more than $530 million in 2027, according to the publication. The companies had then expected the deal to close in the second half of 2026.

Guidance update to come with second-quarter results

Danaher said there is no change to its previously communicated second-quarter and full-year 2026 guidance range, excluding Masimo. The company said it does not expect a material contribution from Masimo in the second quarter and intends to update its full-year 2026 guidance with its second-quarter earnings release to include Masimo's expected contribution.

The release's risk factors also refer to debt Danaher has incurred to finance the Masimo acquisition. Danaher said the consideration owed to former Masimo stockholders will be paid under the terms of the merger agreement.

The acquisition came more than a year after Masimo founder Joe Kiani resigned following a two-year fight with activist investor Politan Capital Management for control of the board, Healthcare Dive reported in February. Katie Szyman, formerly president of advanced patient monitoring at BD, then became Masimo's chief executive.