Form SC 13D/A - General statement of acquisition of beneficial ownership: [Amend]

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

(Rule 13d-101)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO RULE 13d-1(a) AND AMENDMENTS THERETO FILED

PURSUANT TO RULE 13d-2(a)

Under the Securities Exchange Act of 1934

(Amendment No. 8)*

Masimo Corporation

(Name of Issuer)

Common Stock, par value $0.001 per share

(Title of Class of Securities)

574795100

(CUSIP Number)

Quentin Koffey

Politan Capital Management LP

106 West 56^th Street, 10^th Floor

New York, New York 10019

646-690-2830

With a copy to:

Richard M. Brand

Cadwalader, Wickersham & Taft LLP

200 Liberty Street

New York, NY 10281

212-504-6000

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

May 8, 2024

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box. ¨

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 for other parties to whom copies are to be sent.

*	The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 574795100

Page 2

1	NAME OF REPORTING PERSON Politan Capital Management LP
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS OO (See Item 3)
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) ¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
Number of shares beneficially owned by each reporting person with		7	SOLE VOTING POWER 0
		8	SHARED VOTING POWER 4,713,518
		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 4,713,518
11		AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 4,713,518
12		CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES ¨
13		PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 8.9%^*
14		TYPE OF REPORTING PERSON IA

* All percentage calculations set forth herein are based upon the aggregate of 53,085,556 shares of Common Stock outstanding as of March 30, 2024, as reported in the Issuer’s Quarterly Report on Form 10-Q for the period ended March 30, 2024, filed with the Securities and Exchange Commission (the “SEC”) on May 7, 2024 (the “Q1 2024 10-Q”).

CUSIP No. 574795100

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1	NAME OF REPORTING PERSON Politan Capital Management GP LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS OO (See Item 3)
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) ¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
Number of shares beneficially owned by each reporting person with		7	SOLE VOTING POWER 0
		8	SHARED VOTING POWER 4,713,518
		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 4,713,518
11		AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 4,713,518
12		CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES ¨
13		PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 8.9%^*
14		TYPE OF REPORTING PERSON IA

* All percentage calculations set forth herein are based upon the aggregate of 53,085,556 shares of Common Stock outstanding as of March 30, 2024, as reported in the Q1 2024 10-Q.

CUSIP No. 574795100

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1	NAME OF REPORTING PERSON Politan Capital Partners GP LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS OO (See Item 3)
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) ¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
Number of shares beneficially owned by each reporting person with		7	SOLE VOTING POWER 0
		8	SHARED VOTING POWER 4,713,518
		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 4,713,518
11		AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 4,713,518
12		CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES ¨
13		PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 8.9%^*
14		TYPE OF REPORTING PERSON IA

* All percentage calculations set forth herein are based upon the aggregate of 53,085,556 shares of Common Stock outstanding as of March 30, 2024, as reported in the Q1 2024 10-Q.

CUSIP No. 574795100

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1	NAME OF REPORTING PERSON Quentin Koffey
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) x (b) ¨
3	SEC USE ONLY
4	SOURCE OF FUNDS OO (See Item 3)
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) ¨
6	CITIZENSHIP OR PLACE OF ORGANIZATION United States
Number of shares beneficially owned by each reporting person with		7	SOLE VOTING POWER 1,228
		8	SHARED VOTING POWER 4,713,518
		9	SOLE DISPOSITIVE POWER 1,228
		10	SHARED DISPOSITIVE POWER 4,713,518
11		AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 4,714,746*
12		CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES ¨
13		PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 8.9%^**
14		TYPE OF REPORTING PERSON IN

* Includes Mr. Koffey’s 1,228 restricted share units granted to him on June 26, 2023 by virtue of his position as a director on the Board and that vest upon the earliest of the first anniversary of the grant date, the date of the next annual meeting of stockholders, or a change in control of the Issuer.

** Mr. Koffey’s percentage calculations set forth herein are based upon the aggregate of 53,085,556 shares of Common Stock outstanding as of March 30, 2024, as reported in the Q1 2024 10-Q.

CUSIP No. 574795100

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This Amendment No. 8 to Schedule 13D (this “Amendment No. 8”) amends and supplements the Schedule 13D filed on August 16, 2022 (as amended and supplemented through the date of this Amendment No. 8, collectively, the “Schedule 13D”) by the Reporting Persons, relating to the common stock, par value $0.001 per share, of Masimo Corporation, a Delaware corporation (the “Issuer”). Capitalized terms not defined in this Amendment No. 8 shall have the meaning ascribed to them in the Schedule 13D.

The information set forth in response to Item 4 below shall be deemed to be a response to all Items where such information is relevant.

ITEM 4. PURPOSE OF TRANSACTION

Item 4 of the Schedule 13D is hereby amended and supplemented with the following information:

On May 8, 2024, Quentin Koffey, a Reporting Person, submitted a books and records request (the “Demand Letter”) to the Issuer pursuant to Section 220 of the Delaware General Corporation Law, demanding to inspect certain books and records of the Issuer relating to the Issuer’s proposed separation of its consumer business as well as the identity of a joint venture partner that has not yet been disclosed to the full Board.

The Demand Letter is attached hereto as Exhibit 99.10 and is incorporated herein by reference.

ITEM 7.

MATERIAL TO BE FILED AS AN EXHIBIT

Exhibit 99.1	Joint Filing Agreement among Politan Capital Management LP, Politan Capital Management GP LLC, Politan Capital Partners GP LLC, and Quentin Koffey*

Exhibit 99.2	Trading Data*

Exhibit 99.3	Trading Data*

Exhibit 99.4	Form of Verified Complaint, filed with the Delaware Court of Chancery on October 21, 2022*

Exhibit 99.5	Form of Second Amended and Supplemented Complaint, filed as an Exhibit to the Motion for Leave to Amend with the Delaware Court of Chancery on March 10, 2023*

Exhibit 99.6	Form of Engagement and Indemnification Agreement entered into by and between Politan Capital Management LP and Michelle Brennan*

Exhibit 99.7	Trading Data*

Exhibit 99.8	Press Release, dated June 26, 2023*

Exhibit 99.9	Form of Engagement and Indemnification Agreement entered into by and between Politan Capital Management LP and each of William Jellison and Darlene Solomon*

Exhibit 99.10	Demand Letter, dated May 8, 2024

*Previously filed.

CUSIP No. 574795100

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SIGNATURES

After reasonable inquiry and to the best of each of the undersigned’s knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

Date: May 8, 2024

POLITAN CAPITAL MANAGEMENT LP

By:	Politan Capital Management GP LLC, its general partner

By:	/s/ Quentin Koffey
	Name:	Quentin Koffey
	Title:	Managing Member

POLITAN CAPITAL MANAGEMENT GP LLC

By:	/s/ Quentin Koffey
	Name:	Quentin Koffey
	Title:	Managing Member

POLITAN CAPITAL PARTNERS GP LLC

By:	/s/ Quentin Koffey
	Name:	Quentin Koffey
	Title:	Managing Member

QUENTIN KOFFEY

By:	/s/ Quentin Koffey
	Name:	Quentin Koffey

CUSIP No. 574795100

Page 8

INDEX TO EXHIBITS

Exhibit		Description
Exhibit 99.1		Joint Filing Agreement among Politan Capital Management LP, Politan Capital Management GP LLC, Politan Capital Partners GP LLC, and Quentin Koffey*

Exhibit 99.2		Trading Data*

Exhibit 99.3		Trading Data*

Exhibit 99.4		Form of Verified Complaint, filed with the Delaware Court of Chancery on October 21, 2022*

Exhibit 99.5		Form of Second Amended and Supplemented Complaint, filed as an Exhibit to the Motion for Leave to Amend with the Delaware Court of Chancery on March 10, 2023*

Exhibit 99.6		Form of Engagement and Indemnification Agreement entered into by and between Politan Capital Management LP and Michelle Brennan*

Exhibit 99.7		Trading Data*

Exhibit 99.8		Press Release, dated June 26, 2023*

Exhibit 99.9		Form of Engagement and Indemnification Agreement entered into by and between Politan Capital Management LP and each of William Jellison and Darlene Solomon*

Exhibit 99.10		Demand Letter, dated May 8, 2024

*Previously filed.

Exhibit 99.10

Quentin Koffey

Director, Board of Directors of Masimo Corporation

106 West 52nd Street
New York, New York 10019

May 8, 2024

Via Email Only

Masimo Corporation
Attn: Joe Kiani

Chief Executive Officer

52 Discovery

Irvine, California 92618

jkiani@masimo.com

Via Hand Delivery

Masimo Corporation

c/o Corporation Service Company

251 Little Falls Drive

Wilmington, DE 19808

Re: Demand to Inspect Books and Records Pursuant to 8 Del. C. § 220(d)

Dear Mr. Kiani:

I write in my capacity as a member of the Board of Directors (the “Board”) of Masimo Corporation (“Masimo” or the “Company”) to demand that certain books and records of the Company be made available to me pursuant to Section 220(d) of the Delaware General Corporation Law (“Section 220(d)”) concerning the contemplated spin-off (the “Spin-Off”) and/or joint venture (“JV” and, together with the Spin-Off, the “Potential Transactions”) of the Company’s consumer business. Despite my repeated requests, I have not received information as basic and fundamental as even the name of the contemplated JV partner (the “JV Partner”).

The Delaware Court of Chancery has repeatedly held that, as a director of the Company, I have the right to “unfettered access” to the books and records of the Company. See Kortum v. Webasto Sunroofs, Inc., 769 A.2d 113, 118 (Del. Ch. 2000) (“there is a presumption that a sitting director is entitled to unfettered access to the books and records of the corporation for which he sits and certainly is entitled to receive what the other directors are given.”) (emphasis added); Hyde Park Venture Partners Fund III, L.P. v. FairXchange, LLC, 292 A.3d 178, 193 (Del. Ch. 2023) (Section 220(d) “gives sitting directors a presumptive right to obtain information from the corporation.”); Sinchareonkul v. Fahnemann, 2015 WL 292314, at *5 (Del. Ch. Jan. 22, 2015) (“One obvious and familiar right is a director’s ability to obtain information about the corporation she serves. But perhaps the most fundamental right is the ability to participate in the board’s collective deliberations and any resulting exercise of its power and authority over the business and affairs of the corporation.”); Holdgreiwe v. Nostalgia Network, Inc., 1993 WL 144604, at *7 (Del. Ch. Apr. 29, 1993) (“The rights of directors to access to the corporate books and records are recognized by Delaware law as of fundamental importance and a necessary concomitant to the imposition upon directors of fiduciary duties. . . . If [a director’s] inspection of [a corporation’s] records is to effectuate its purpose of enabling him to determine whether management wrongdoing has occurred, his access to [the corporation’s] records must necessarily be broad and unrestricted.”).

Pursuant to that authority, I hereby demand that the following books and records of the Company be made available to me for inspection and copying:

All documents¹ identifying the JV Partner;

All documents and communications relating to the Potential Transactions, including, without limitation, communications with the Company’s counsel, financial advisors, or any other advisors;

All communications between the Company’s management and/or any member of the Board (and their respective agents) and the JV Partner and/or its agents;

All reports, presentations, notes, and other documents considered by the Company’s management and/or any member of the Board (and their respective agents) in evaluating the Potential Transactions and/or JV Partner;

All documents, presentations, and analyses prepared by any outside counsel, consultants, or advisors on behalf of the Company, management, and/or any member of the Board concerning the Potential Transactions and/or JV Partner;

All documents, including any term sheets, detailing the proposed terms of the Potential Transactions; and

All documents demonstrating Mr. Kiani’s actual or contemplated economic interest (if any), leadership role (if any), or governance rights (if any) with respect to the JV, the JV Partner, or as a result of the Potential Transactions.

I am requesting the above-listed documents, all of which I have requested previously, for purposes related to my role as a director of the Company, including but not limited to, discharging my fiduciary duties as a director to conduct due diligence on and otherwise consider the Potential Transactions. Furthermore, Mr. Kiani has made the highly unusual and entirely inappropriate demand that directors sign a non-disclosure agreement. Directors have fiduciary duties to the Company that control and suffice. Therefore, production of the aforementioned information should not be conditioned on the entry of such an agreement.

As explained in my letter to Mr. Kiani dated May 2, 2024, I have serious concerns that Mr. Kiani intends to cause the Company, without proper Board oversight or review, to enter into a binding agreement in connection with one of the Potential Transactions prior to the Company’s July 25, 2024 annual meeting in order to entrench his control of the Company’s assets and/or entrench himself in office in advance of a contested election.

The requested materials should be produced as kept in the ordinary course of business and will not be burdensome to produce. I have authorized my counsel, Schulte Roth & Zabel LLP and Cadwalader Wickersham & Taft LLP (and their respective partners, associates, employees and other designees) to conduct the inspection. Their contact information is as follows:

Michael E. Swartz
michael.swartz@srz.com
(212) 756-2471

Richard M. Brand
richard.brand@cwt.com
(212) 504-5757

Please confirm that the requested materials will be produced to Mr. Swartz immediately, and in no event later than May 10, 2024. If you have any questions or are unwilling to produce the books and records for any reason, please inform me immediately so that I can commence legal action in the Delaware Court of Chancery pursuant to Section 220(d).

¹ The term “document,” as used herein, shall mean any document or thing in the broadest sense permitted under the Court of Chancery Rules and common law interpreting such rules. The term “document” further means any document now or at any time in your possession, custody or control (together with any of your predecessors, successors, affiliates, subsidiaries, or divisions thereof, and their officers, directors, employees, agents and attorneys).