[Form 4] TREX CO INC Insider Trading Activity

Rhea-AI Filing Summary

Melkeya McDuffie, a director of TREX CO INC (TREX), reported the acquisition of 49 shares of the issuer's common stock on 10/01/2025 at a reported price of $51.94 per share. After the transaction the reporting person beneficially owns 3,653 shares in a direct ownership form. The filing discloses that the acquired units are restricted stock units that will vest on the first anniversary of the grant. The Form 4 is signed by power of attorney on 10/02/2025.

Positive

• Reported acquisition of 49 shares, indicating insider accumulation
• Restricted stock units vesting on first anniversary provides clear timing for when shares become unrestricted

Negative

• None.

Insights

Corporate Governance Analyst

Director purchased company stock; holdings now 3,653 shares.

The filing shows a director-level insider acquired 49 common shares, increasing direct beneficial ownership to 3,653 shares. This is a straightforward disclosure of insider buying via a restricted stock unit award rather than an open-market trade.

The disclosure that the award vests on the first anniversary is material to understanding timing of ownership becoming unrestricted; no other conditions or additional transactions are disclosed.

Equity Compensation Specialist

Acquisition is from a restricted stock unit grant that vests in one year.

The Form 4 lists the transaction code and an explicit explanation that the award "will vest on the first anniversary of the grant." The reported price per share is $51.94, and the transaction is recorded as an acquisition of 49 shares.

This entry documents standard RSU treatment; the filing does not disclose additional awards, forfeiture provisions, or performance conditions.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

McDuffie Melkeya

(Last) (First) (Middle)

C/O TREX COMPANY, INC.

2500 TREX WAY

(Street)

WINCHESTER VA 22601

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
TREX CO INC [ TREX ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
10/01/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	10/01/2025		A(1)		49	A	$51.94	3,653	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. This restricted stock unit award will vest on the first anniversary of the grant.

	/s/ Amy M. Fernandez by power of attorney	10/02/2025
	** 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 4 (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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What did the TREX insider file on Form 4?

The Form 4 reports that director Melkeya McDuffie acquired 49 shares on 10/01/2025 at $51.94 per share and now beneficially owns 3,653 shares.

Were the shares purchased or granted for TREX (TREX)?

The filing shows the entries as an acquisition of common stock via a restricted stock unit award, not an open-market purchase.

When do the restricted stock units vest?

The Form 4 explicitly states the award "will vest on the first anniversary of the grant."

Who signed the Form 4 for the reporting person?

The form was signed by Amy M. Fernandez by power of attorney on 10/02/2025.

How much beneficial ownership does the reporting person hold after the transaction?

Following the reported transaction the reporting person beneficially owns 3,653 shares in direct form.