• Masimo CEO Joe Kiani revealed what he called confidential information to a major investor in March, 12 hours before it was released to the public, according to court filings.
• The documents, partially unsealed Friday, are related to ongoing litigation between Masimo and activist Politan.
• Politan is in the midst of its second proxy battle with Masimo, which makes devices for monitoring how much oxygen is in a person's blood.

Masimo CEO Joe Kiani, whose medical-technology company is in the midst of a proxy battle with activist Politan, revealed what he called confidential information to a major investor 12 hours before it was released to the public, according to court filings.

The documents, partially unsealed on Friday, are related to ongoing litigation between Politan and Masimo, which makes devices for monitoring the amount of oxygen in a person's blood. Politan is seeking to replace two directors, including Kiani, with its own candidates at a shareholder meeting later this month.

Included in the latest filing is a March email from Kiani to Naveen Yalamanchi, a portfolio manager at RTW Investments, informing him about an announcement that was coming the following day. The unsealed documents show other calls and messages between Kiani and employees of RTW, a New York-based firm that focuses on health care.

In addition to taking on Masimo, Politan has accused RTW of a so-called empty voting scheme, or voting its shares in favor of management's slate of directors even though it no longer actually owned the shares underlying its votes.

Other documents unsealed Friday indicate that Masimo was aware of RTW's efforts. They include communications from Masimo advisors showing that the company was aware RTW was amassing a large position and was supportive of Kiani's leadership.

"As a long term shareholder, I wanted to see what you think of this PR before we put it out," Kiani wrote in an email, titled "Confidential PR and 8K for tomorrow before the market opens."

The filing that was published the next day confirmed activist investor Politan had initiated its second proxy fight and was nominating two board members. Politan has pointed to Masimo's underperformance and Kiani's disastrous acquisition of a consumer business two years ago, and has been pushing the company to explore a spinoff.

The Wall Street Journal had, the previous week, reported that the second proxy fight was going to be launched.

Masimo is best known for its litigation with Apple over the company's use of pulse-oximetry technology in the Apple Watch. Kiani is also a close friend to President Joe Biden and has donated to his campaigns. One of Kiani's top advisors in the proxy fight is Greg Schultz, who was Biden's campaign manager in 2020.

"Please don't trade on anything until this is out, which is going to go out before the market opens tomorrow morning," Kiani wrote in the email to Yalamanchi. The message included two attachments and a timestamp indicating when the press release would publish.

An SEC rule known as Regulation FD requires that if a company makes information available to certain individuals, including large shareholders, it must promptly make that information available to everyone.

Politan launched an earlier proxy battle at Masimo, resulting in the activist getting two board seats in 2023, including one for managing partner Quentin Koffey.

A spokesperson for Masimo declined to comment. A representative for Politan didn't immediately respond to a request for comment.

Correction: This article has been revised to reflect that Masimo makes devices for monitoring the amount of oxygen in a person's blood. A previous version mischaracterized the function of the devices.

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