Paul Moskowitz - Sep 12, 2025 Form 4 Insider Report for Waystar Holding Corp. (WAY)

Role: Director, 10%+ Owner
Signature: /s/ Paul Moskowitz
Stock symbol: WAY
Transactions as of: Sep 12, 2025
Transactions value $: -$168,412,400
Form type: 4
Date filed: 9/16/2025, 04:30 PM
Previous filing: May 20, 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Moskowitz Paul G	Director, 10%+ Owner	C/O BAIN CAPITAL PRIVATE EQUITY, LP, 200 CLARENDON STREET, BOSTON	/s/ Paul Moskowitz	2025-09-16	0001997404

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	WAY	Common Stock, par value $0.01 per share	Sale	-$168M	-4.3M	-23.79%	$39.21	13.8M	Sep 12, 2025	See Footnote	F1, F2, F3
transaction	WAY	Common Stock, par value $0.01 per share	Other		-516K	-3.75%		13.2M	Sep 12, 2025	See Footnote	F1, F2, F4

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Represents shares held by BCPE Derby Investor, LP ("Derby Investor") and BCPE Derby (DE) SPV, LP ("Derby SPV Investor"). Bain Capital Investors, LLC ("BCI") is the manager of Bain Capital Partners XI, L.P. ("Partners XI"), which is the general partner of Bain Capital Fund XI, L.P. ("Fund XI"). Fund XI is the (i) sole member of BCPE Derby GP, LLC ("Derby GP"), which is the general partner of Derby Investor and (ii) sole member of BCPE Derby (DE) SPV, LLC ("Derby SPV GP" and, together with BCI, Partners XI, Fund XI, Derby GP, Derby Investor and Derby SPV Investor, the "Bain Capital Entities"), which is the general partner of Derby SPV Investor.
F2	(Continued from footnote 1) Paul G Moskowitz, a member of the board of directors of Waystar Holding Corp. (the "Issuer"), is a Partner of BCI. By virtue of the relationships described in this footnote, Mr. Moskowitz may be deemed to share voting and dispositive power with respect to the shares of the Issuer's common stock, par value $0.01 per share (the "Common Stock"), held by the Bain Capital Entities. Mr. Moskowitz disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.
F3	Pursuant to a registered public offering that closed on September 12, 2025, 298,303 shares of Common Stock were sold by Derby Investor and 3,996,836 shares of Common Stock were sold by Derby SPV Investor at a price of $39.21 (net of underwriting discount).
F4	On September 12, 2025, Derby Investor distributed 397,013 shares of Common Stock and Derby SPV Investor distributed 119,358 shares of Common Stock to one or more of their respective members or partners in connection with certain charitable gifts made by such members or partners or their direct or indirect owners. Such shares of Common Stock are subject to lock-up agreements that, subject to certain exceptions, restrict the sale of such shares until November 11, 2025 except with the prior written consent of J.P. Morgan Securities LLC.