SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person* BAIN CAPITAL INVESTORS LLC (Last) (First) (Middle) C/O BAIN CAPITAL PRIVATE EQUITY, LP 200 CLARENDON STREET (Street) BOSTON MA 02116 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 06/06/2024	3. Issuer Name and Ticker or Trading Symbol Waystar Holding Corp. [ WAY ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)	5. If Amendment, Date of Original Filed (Month/Day/Year)
			6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock	27,980,417	I	See footnotes(1)(2)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person* BAIN CAPITAL INVESTORS LLC (Last) (First) (Middle) C/O BAIN CAPITAL PRIVATE EQUITY, LP 200 CLARENDON STREET (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* BCPE Derby Investor, LP (Last) (First) (Middle) 200 CLARENDON STREET (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* BCPE Derby GP, LLC (Last) (First) (Middle) 200 CLARENDON STREET (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Bain Capital Fund XI, L.P. (Last) (First) (Middle) 200 CLARENDON STREET (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Bain Capital Partners XI, L.P. (Last) (First) (Middle) 200 CLARENDON STREET (Street) BOSTON MA 02116 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. Represents shares of Common Stock held by BCPE Derby Investor, LP ("Derby Investor").

2. Bain Capital Fund XI, LP ("Fund XI") is the sole member of BCPE Derby GP, LLC ("Derby GP"), which is the general partner of Derby Investor. Bain Capital Investors, LLC ("BCI") is the manager of Bain Capital Partners XI, LP ("Partners XI" and, together with BCI, Derby GP, Derby Investor and Fund XI, the "Bain Capital Entities"), which is the general partner of Fund XI. As a result, each of the Bain Capital Entities may be deemed to share voting and dispositive power with respect to the shares of Common Stock held by Derby Investor. Each of the Bain Capital Entities disclaims beneficial ownership of such securities, except to the extent of its pecuniary interest therein.

	Bain Capital Investors, LLC, By: /s/ David Humphrey, Title: Authorized Signatory	06/07/2024
	BCPE Derby Investor, LP, By: BCPE Derby GP, LLC, its general partner, By: Bain Capital Fund XI, L.P. its member, By: Bain Capital Partners XI, L.P. its general partner, By: Bain Capital Investors, LLC its general partner, By: /s/ David Humphrey, Title: A	06/07/2024
	BCPE Derby GP, LLC, By: Bain Capital Fund XI, L.P. its member, By: Bain Capital Partners XI, L.P. its general partner, By: Bain Capital Investors, LLC its general partner, By: /s/ David Humphrey, Title: Authorized Signatory	06/07/2024
	Bain Capital Fund XI, LP, By: Bain Capital Partners XI, LP, its general partner, By: Bain Capital Investors, LLC, its manager, By: /s/ David Humphrey, Title: Authorized Signatory	06/07/2024
	Bain Capital Partners XI, LP, By: Bain Capital Investors, LLC, its manager, By: /s/ David Humphrey, Title: Authorized Signatory	06/07/2024
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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