Statement of Changes in Beneficial Ownership (4)

FORM 4

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

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

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

1. Name and Address of Reporting Person * Harrison Michelle	2. Issuer Name and Ticker or Trading Symbol CENTURY ALUMINUM CO [ CENX ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director                    _____ 10% Owner __X__ Officer (give title below)    _____ Other (specify below) Sr. VP Finance & Treasurer
(Last)          (First)          (Middle) C/O CENTURY ALUMINUM COMPANY, ONE SOUTH WACKER DRIVE, SUITE 1000	3. Date of Earliest Transaction (MM/DD/YYYY) 12/31/2019
(Street) CHICAGO, IL 60606 (City)        (State)        (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	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. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. 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	12/31/2019		F		3340 (1)	D	$7.76	69031 (2)	D
Common Stock	1/1/2020		A		9057 (3)	A	$0	78088 (4)	D
Common Stock								352.5075 (5)	I	By 401(k) plan

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. 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		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 of Derivative Security: 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)	Reports shares withheld by the Issuer to satisfy tax obligations in connection with the vesting of performance share units granted to the Reporting Person.
(2)	Includes unvested performance share units granted to the Reporting Person pursuant to Issuer's 2018-2020 and 2019-2021 Long-Term Incentive Plans under Rule 16b-3(d).
(3)	Represents time vesting performance share units granted to the Reporting Person in connection with the Issuer's 2020-2022 Long-Term Incentive Plan under Rule 16b-3(d), all of which will vest in the ordinary course on the last day of the Plan Period, December 31, 2022.
(4)	Includes unvested performance share units granted to the Reporting Person pursuant to Issuer's 2018-2020, 2019-2021 and 2020-2022 Performance Share Programs under a Rule 16b-3(d) plan.
(5)	As reported by 401(k) plan trustee on December 31, 2019.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Harrison Michelle C/O CENTURY ALUMINUM COMPANY ONE SOUTH WACKER DRIVE, SUITE 1000 CHICAGO, IL 60606			Sr. VP Finance & Treasurer

Signatures
/s/ Morgan F. Walbridge, Attorney-in-Fact for Michelle Harrison		1/3/2020
**Signature of Reporting Person		Date