EXHIBIT 3.25(a)

CERTIFICATE OF INCORPORATION

OF

LYONDELL PETROCHEMICAL G.P. INC.

* * *

1. The name of the corporation is LYONDELL PETROCHEMICAL G.P. INC.

2. The address of its registered office in the State of Delaware is Corporation Trust Center, 1209 Orange Street, in the City of Wilmington, County of New Castle. The name of its registered agent at such address is The Corporation Trust Company.

3. The nature of the business or purposes to be conducted or promoted is:

To engage in any lawful act or activity for which corporations may be organized under the General Corporation Law of Delaware.

4. The total number of shares of stock which the corporation shall have authority to issue is: Three Thousand(3,000) and the par value of each of such shares is No Dollars and One Cents($0.01) amounting in the aggregate to Thirty Dollars and Zero Cents ($30).

5. The name and mailing address of each incorporator is as follows:

NAME	MAILING ADDRESS
Mary Ann Brzoska	1209 Orange Street, Wilmington, Delaware 19801

The name and mailing address of each person who is to serve as a director until the first annual meeting of the stockholders or until a successor is elected and qualified, is as follows.

NAME	MAILING ADDRESS
Dan F. Smith	3221 Avalon Place, Houston, TX 77019
Jeffrey R. Pendergraft	714 Tirrell, Houston, TX 77019
Clif B. Currin	2618 Rustic Woods Drive, Kingwood, TX 77345

6. The corporation is to have perpetual existence.

7. In furtherance and not in limitation of the powers conferred by statute, the board of directors is expressly authorized.

To make, alter or repeal the by-laws of the corporation.

8. Elections of directors need not be by written ballot unless the by-laws of the corporation shall so provide.

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Meetings of stockholders may be held within or without the State of Delaware, as the by-laws may provide. The books of the corporation may be kept (subject to any provision contained in the statutes) outside the State of Delaware at such place or places as may be designated from time to time by the board of directors or in the by-laws of the corporation.

9. The corporation reserves the right to amend, alter, change or repeal any provision contained in this Certificate of Incorporation, in the manner now or hereafter prescribed by statute, and all rights conferred upon stockholders herein are granted subject to this reservation.

10. A director of the corporation shall not be personally liable to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director except for liability (i) for any breach of the director’s duty of loyalty to the corporation or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the Delaware General Corporation Law, or (iv) for any transaction from which the director derived any improper personal benefit.

11. All business shall be transacted outside the state of Texas.

WE, THE UNDERSIGNED, being each of the incorporators hereinbefore named, for the purpose of forming a corporation pursuant to the General Corporation Law of the State of Delaware, do make this Certificate, hereby declaring and certifying that this is our act and deed and the facts herein stated are true, and accordingly have hereunto set our hands this Nineteenth day of September, 1997.

/s/ Mary Ann Brzoska

Mary Ann Bzoska

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CERTIFICATE OF AMENDMENT

OF

CERTIFICATE OF INCORPORATION

LYONDELL PETROCHEMICAL G.P. INC.

LYONDELL PETROCHEMICAL G.P. INC., a corporation organized and existing under and by virtue of the Delaware General Corporation Law, DOES HEREBY CERTIFY:

FIRST: That the Board of Directors of said corporation, by the unanimous written consent of its members, filed with the minutes of the Board, adopted a resolution proposing and declaring advisable the following amendment to the Certificate of Incorporation of said corporation:

RESOLVED, that the Certificate of Incorporation of LYONDELL PETROCHEMICAL G.P. INC., be amended by changing the First Article thereof, so that, as amended, said Article shall be and read as follows:

“1. The name of the corporation is LYONDELL LP4 INC.”

SECOND: That in lieu of a meeting and vote of stockholders, the stockholders have given unanimous written consent to said amendment in accordance with the provisions of Section 228 of the Delaware General Corporation Law.

THIRD: That the aforesaid amendment was duly adopted in accordance with the applicable provisions of Sections 242 and 228 of the Delaware General Corporation Law.

FOURTH: That the effective date of this Certificate of Amendment shall be November 29, 2004.

IN WITNESS WHEREOF, said LYONDELL PETROCHEMICAL G.P. INC. has caused this certificate to be signed by Allen C. Holmes, its Vice President, and attested by Michelle S. Miller, its Secretary, this 23rd day of November, 2004.

		LYONDELL PETROCHEMICAL G.P. INC.
Attest:	/s/ Michelle S. Miller	By:	/s/ Allen C. Holmes
	Michelle S. Miller, Secretary		Allen C. Holmes, Vice President