ITEM SECOND IRR. TRUST FBO ANDREA P. LUCAS u/a of STEFANIE W. LUCAS dated October 5, 2001 - May 20, 2025 Form 4 Insider Report for Vertex, Inc. (VERX)

Role: 13(d) Group Member, 10%+ Owner
Signature: /s/ Lisa Coleman, Attorney-in-Fact
Stock symbol: VERX
Transactions as of: May 20, 2025
Transactions value $: $0
Form type: 4
Date filed: 5/22/2025, 04:12 PM
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
ITEM SECOND IRR. TRUST FBO ANDREA P. LUCAS u/a of STEFANIE W. LUCAS dated October 5, 2001	13(d) Group Member, 10%+ Owner	C/O VERTEX, INC., 2301 RENAISSANCE BLVD, KING OF PRUSSIA	/s/ Lisa Coleman, Attorney-in-Fact	2025-05-22	0001818835

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	VERX	Class A Common Stock	Conversion of derivative security	$0	+400K		$0.00	400K	May 20, 2025	Direct

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	VERX	Class B Common Stock	Conversion of derivative security	$0	-400K	-20.16%	$0.00	1.58M	May 20, 2025	Class A Common Stock	400K		Direct	F1, F2

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

Explanation of Responses:

Id	Content
F1	The Class B Common Stock is convertible at any time at the option of the holder into one share of the Issuer's Class A Common Stock and has no expiration date. The Class B Common Stock will automatically convert into shares of the Issuer's Class A Common Stock on a one-to-one basis upon either (1) any transfer of the Class B Common Stock by the holder, whether or not for value, subject to certain exceptions or (2) the voting power of the Issuer's outstanding Class B Common Stock representing less than 10% of the combined voing power of all of the Issuer's outstanding common stock.
F2	The Form 3 originally filed by the reporting person understated the reporting person's ownership of Class B Common Stock by approximately 2,744.164 shares. This Form 4 reflects the correct number of shares.

Content

The Class B Common Stock is convertible at any time at the option of the holder into one share of the Issuer's Class A Common Stock and has no expiration date. The Class B Common Stock will automatically convert into shares of the Issuer's Class A Common Stock on a one-to-one basis upon either (1) any transfer of the Class B Common Stock by the holder, whether or not for value, subject to certain exceptions or (2) the voting power of the Issuer's outstanding Class B Common Stock representing less than 10% of the combined voing power of all of the Issuer's outstanding common stock.

The Form 3 originally filed by the reporting person understated the reporting person's ownership of Class B Common Stock by approximately 2,744.164 shares. This Form 4 reflects the correct number of shares.