FORM 4 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OMB APPROVAL OMB Number: 3235-0287 Expires: January 31, 2005

FORM 4

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

OMB APPROVAL

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

OMB Number: 3235-0287
Expires: January 31, 2005
Estimated average burden
hours per response. . .0.5

Filed By
Romeo and Dye's
Section 16 Filer
www.section16.net

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b). Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940 Estimated average burden hours per response.... 0.5

1. Name and Address of Reporting Person* Watson Joseph D.	2. Issuer Name and Ticker or Trading Symbol Premcor Inc. (PCO)		6. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner X Officer (give title below) Other (specify below) Senior Vice President - Corporate Development
(Last) (First) (Middle) c/o Premcor Inc. 1700 E. Putnam Ave., Suite 500	3. I.R.S. Identification Number of Reporting Person, if an entity (voluntary)	4. Statement for Month/Day/Year 01/29/03
(Street) Greenwich, CT 06870		5. If Amendment, Date of Original (Month/Day/Year)	7. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person Form filed by More than One Reporting Person
(City) (State) (Zip)	Table I — Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

(Print or Type Responses)
1. Title of Security (Instr. 3)	2. Trans- action Date (Month/ Day/ Year)	2A. Deemed Execution Date, if any (Month/Day/ Year)	3. Trans- action Code (Instr. 8)		4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 & 5)			5. Amount of Securities Beneficially Owned Follow- ing Reported Transactions(s) (Instr. 3 & 4)	6. Owner- ship Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
1.	Name and Address of Reporting Person*	2.	Issuer Name and Ticker or Trading Symbol			6.	Relationship of Reporting Person(s) to Issuer
			Code	V	Amount	(A) or (D)	Price
							(Check all applicable)
Common Stock	01/29/03		P		5,000	A	19.20	5,000	D
Occidental Petroleum Corporation			Premcor Inc.
			PCO				Director	X 10% Owner
(Last) (First) (Middle)							Officer (give title	Other (specify
Occidental Petroleum Corporation		3.	I.R.S. Identification Number	4.	Statement for Month/Day/Year		below)	below)
10889 Wilshire Boulevard			of Reporting Person, if an
			entity (voluntary)		01/29/2003
(Street)
				5.	If Amendment, Date of Original
Los Angeles, California 90024			95-4035997		(Month/Year)
						7.	Individual or Joint/Group Filing (Check Applicable Line)
(City) (State) (Zip)							Form filed by One Reporting Person
							X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

Title of Security

Transaction

2a.

Deemed

Transaction Code

Securities Acquired (A) or

Amount of

Ownership

Nature of

(Instr. 3)

Date

Execution

Disposed of (D)

Securities

Form:

Indirect

Date, if any

(Instr. 8)

Beneficially

Direct (D) or

Beneficial

(Month/Day/

(Instr. 3, 4 and 5)

Owned at End

Indirect (I)

Ownership

Year)

(Month/Day/

of Month

Year)

Code

Amount

(A) or (D)

Price

(Instr. 3 and 4)

(Instr. 4)

Common Stock

01/29/2003

274,573

$19.20

1,908,209

Common Stock

01/29/2003

1,025,427

$19.20

7,126,437

(1)

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).

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).

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 control number

~~Page~~FORM 14 (continued) Table II - Derivative Securities Acquired, Disposed of, 7 or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

FORM 4 (continued) Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned

1. Title of Derivative Security

(Instr. 3)

2. Conver-
sion or
Exercise
Price of Derivative Security

3. Trans-
action Date

(Month/
Day/
Year)

3A. Deemed
Execution
Date,
if any
(Month/
Day/
Year)

4. Trans-
action
Code

(Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D)

(Instr. 3, 4 & 5)

6. Date Exercisable
and Expiration
Date
(Month/Day/
Year)

7. Title and Amount of Underlying Securities
(Instr. 3 & 4)

8. Price of Derivative Security
(Instr. 5)

9. Number of
Derivative
Securities
Beneficially
Owned
Following
Reported Transaction(s)
(Instr. 4)

10. Owner-
ship Form
of Deriv-
ative
Security:
Direct (D)
or Indirect (I)
(Instr. 4)

11. Nature of Indirect Beneficial Ownership
(Instr. 4)

Code

(A)

(D)

Date Exer-cisable

Expira-
tion
Date

Title

Amount or Number of
Shares

Title of Derivative

Conver-

Trans-

3a.

Deemed

Transac-

Number of Deriv-

Date Exer-

Title and Amount of

Price

Number

10.

Owner-

11.

Na-

Security

sion or

action

Execu-

tion Code

ative Securities

cisable and Ex-

Underlying

of Der-

ship

ture

(Instr. 3)

Exercise

Date

tion

(Instr. 8)

Acquired (A) or

piration Date

Securities

Deriv-

ivative

Form

of In-

Price of

Date,

Disposed of (D)

(Month/Day/

(Instr. 3 and 4)

ative

Secur-

of De-

direct

Deriv-

(Month/

if any

(Instr. 3, 4 and 5)

Year)

Secur-

ities

rivative

Bene-

ative

Day/

ity

Bene-

Secur-

ficial

Security

Year)

(Month/

ficially

ity:

Own-

Day/

(Instr.

Owned

Direct

ership

Year)

Date

Expira-

Amount or

at End

(D) or

(Instr. 4)

Code

(A)

(D)

Exer-

tion

Title

Number of

Indi-

cisable

Date

Month

rect (I)

(Instr. 4)

Explanation of Responses:

(1) Owned by Occidental C.O.B. Partners, an indirect wholly-owned subsidiary of Occidental Petroleum Corporation.

Explanation of Responses:

**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations.		OCCIDENTAL PETROLEUM CORPORATION
	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.	By:	/s/ STEPHEN I. CHAZEN		January 29, 2003
		If space is insufficient, see Instruction 6 for procedure.
				**Signature of Reporting Person		Date
Potential persons who are to respond to the collection of information contained in this form are not				Name:	Stephen I. Chazen
required to respond unless the form displays a currently valid OMB control number.				Title:	Chief Financial Officer and Executive Vice President - Corporate Development

By: /s/ Rosemary L. Klein
Attorney-in-Fact
**Signature of Reporting Person

01/30/03
Date

~~Page~~**Intentional 2misstatements or omissions of 7 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.

JOINT FILER INFORMATION

Name:	Occidental C.O.B. Partners
Address:	110 West 7th Street P.O. Box 300 Tulsa, Oklahoma 74102
Designated Filer:	Occidental Petroleum Corporation
Issuer & Ticker Symbol:	Premcor Inc. (PCO)
Date of Event Requiring Statement:	01/29/2003
Signature:	OCCIDENTAL C.O.B. PARTNERS by OXY USA Inc., its managing partner
	By:	/s/ STEPHEN I. CHAZEN
		Stephen I. Chazen Executive Vice President

Page 3 of 7

JOINT FILER INFORMATION

Name:	Placid Oil Company
Address:	10889 Wilshire Boulevard Los Angeles, California 90024
Designated Filer:	Occidental Petroleum Corporation
Issuer & Ticker Symbol:	Premcor Inc. (PCO)
Date of Event Requiring Statement:	01/29/2003
Signature:	PLACID OIL COMPANY
	By:	/s/ STEPHEN I. CHAZEN
		Stephen I. Chazen Executive Vice President

Page 4 of 7

JOINT FILER INFORMATION

Name:	OXY USA Inc.
Address:	5 Greenway Plaza Houston, Texas 77046
Designated Filer:	Occidental Petroleum Corporation
Issuer & Ticker Symbol:	Premcor Inc. (PCO)
Date of Event Requiring Statement:	01/29/2003
Signature:	OXY USA INC.
	By:	/s/ STEPHEN I. CHAZEN
		Stephen I. Chazen Executive Vice President

Page 5 of 7

JOINT FILER INFORMATION

Name:	Occidental Oil and Gas Holding Corporation
Address:	10889 Wilshire Boulevard Los Angeles, California 90024
Designated Filer:	Occidental Petroleum Corporation
Issuer & Ticker Symbol:	Premcor Inc. (PCO)
Date of Event Requiring Statement:	01/29/2003
Signature:	OCCIDENTAL OIL AND GAS HOLDING CORPORATION
	By:	/s/ STEPHEN I. CHAZEN
		Stephen I. Chazen Executive Vice President

Page 6 of 7

JOINT FILER INFORMATION

Name:	Occidental Petroleum Investment Co.
Address:	10889 Wilshire Boulevard Los Angeles, California 90024
Designated Filer:	Occidental Petroleum Corporation
Issuer & Ticker Symbol:	Premcor Inc. (PCO)
Date of Event Requiring Statement:	01/29/2003
Signature:	OCCIDENTAL PETROLEUM INVESTMENT CO.
	By:	/s/ J.R. HAVERT
		J. R. Havert Vice President and Treasurer

Page 7 of 7

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