ITEM SECOND IRR. TRUST FBO KYLE R. WESTPHAL u/a of JEFFREY R. WESTPHAL dated October 5, 2001 - 09 Mar 2026 Form 4 Insider Report for Vertex, Inc. (VERX)

Role: 10%+ Owner
Signature: /s/ Joshua Levine, as Trustee
Issuer symbol: VERX
Transactions as of: 09 Mar 2026
Net transactions value: -$150,477
Form type: 4
Filing time: 09 Mar 2026, 19:43:13 UTC
Previous filing: 23 Jan 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
ITEM SECOND IRR. TRUST FBO KYLE R. WESTPHAL u/a of JEFFREY R. WESTPHAL dated October 5, 2001	10%+ Owner	C/O VERTEX, INC., 2301 RENAISSANCE BLVD, KING OF PRUSSIA	/s/ Joshua Levine, as Trustee	09 Mar 2026	0001819244

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	VERX	Class A Common Stock	Purchase	$150,477	-10,000	-0.81%	$15.05	1,221,100	09 Mar 2026	Direct	F1

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

Explanation of Responses:

Id	Content
F1	The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $15.02 to $15.06. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.