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

Role: 13(d) Group Member, 10%+ Owner
Signature: /s/ Lisa Coleman, Attorney-in-Fact
Issuer symbol: VERX
Transactions as of: 20 May 2025
Net transactions value: $0
Form type: 4
Filing time: 22 May 2025, 16:13:51 UTC
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
ITEM SECOND IRR. TRUST FBO MELANIE H. 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	22 May 2025	0001818853

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	+300,000		$0.000000	300,000	20 May 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	-300,000	-15%	$0.000000	1,641,750	20 May 2025	Class A Common Stock	300,000		Direct	F1

* 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.

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.