10-K/A

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K/A

(AMENDMENT NO. 1)

[X] ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2011

[ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from _______________________________ to_________________________________________

Commission File Number: 0-52105

KAISER ALUMINUM CORPORATION

(Exact name of registrant as specified in its charter)

Delaware		94-3030279
(State or other jurisdiction of incorporation or organization)		(I.R.S. Employer Identification No.)
27422 Portola Parkway, Suite 200, Foothill Ranch, California		92610-2831
(Address of principal executive offices)		(Zip Code)
	(949) 614-1740
(Registrant's telephone number, including area code)
Securities registered pursuant to Section 12(b) of the Act:
Title of each class		Name of each exchange on which registered
Common stock, par value $0.01 per share		Nasdaq Stock Market LLC
Securities registered pursuant to section 12(g) of the Act:
	NONE

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes þ No o

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of Act. Yes o No þ

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes þ No o

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes þ No o

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405 of this chapter) is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment of this Form 10-K.    þ

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer þ	Accelerated filer o
Non-accelerated filer o  (Do not check if a smaller reporting company)	Smaller reporting company o

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o No þ

The aggregate market value of the registrant’s common stock held by non-affiliates of the registrant as of the last business day of the registrant’s most recently completed second fiscal quarter (June 30, 2011) was approximately $0.9 billion.

As of February 23, 2012, there were 19,253,185 shares of common stock of the registrant outstanding.

EXPLANATORY NOTE

This Amendment No. 1 on Form 10-K/A ("Amendment No. 1") amends the Kaiser Aluminum Corporation (the "Company'")Annual Report on Form 10-K of for the year ended December 31, 2011, as filed with the Securities and Exchange Commission (the “SEC”) on February 29, 2012 (“Form 10-K"). The purpose of this Amendment No. 1 is to amend Item 9A. Controls and Procedures to replace an inadvertent reference to "our disclosure controls and procedures" with a reference to "our internal control over financial reporting."  See the third paragraph under the caption "Management's Annual Report on Internal Control Over Financial Reporting." While the foregoing items have been updated, no other items in the Form 10-K are amended. This Amendment No. 1 speaks as of the original filing date of the Form 10-K, does not reflect events that may have occurred subsequent to the original filing date, and except as specifically described in the immediately preceding paragraph, does not modify or update in any way disclosures made in the Form 10-K.

Item 9A.Controls and Procedures

Evaluation of Disclosure Controls and Procedures. We maintain disclosure controls and procedures that are designed to ensure that information required to be disclosed in our reports under the Securities Exchange Act of 1934 is processed, recorded, summarized and reported within the time periods specified in the Securities and Exchange Commission’s rules and forms and that such information is accumulated and communicated to management, including the principal executive officer and principal financial officer, to allow for timely decisions regarding required disclosure. In designing and evaluating the disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives, and management is required to apply its judgment in evaluating the cost-benefit relationship of possible controls and procedures. An evaluation of the effectiveness of the design and operation of our disclosure controls and procedures was performed as of the end of the period covered by this Report under the supervision of and with the participation of our management, including the principal executive officer and principal financial officer. Based on that evaluation, our principal executive officer and principal financial officer concluded that our disclosure controls and procedures were not effective as of December 31, 2011 because of the identification of a material weakness relating to our review of the completeness and accuracy of the information used to value the postretirement benefit obligations of the voluntary employee's beneficiary association that provides benefits for certain eligible retirees represented by certain unions and their spouses and eligible dependents (the “Union VEBA”). Information regarding the identified material weakness and the resulting remediation activities are discussed more fully below in Management's Annual Report on Internal Control Over Financial Reporting.

t    Management’s Annual Report on Internal Control Over Financial Reporting. Our management is responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rule 13a-15(f) under the Securities Exchange Act of 1934. Our internal control over financial reporting is designed under the supervision of our principal executive officer and principal financial officer, and effected by our Board of Directors, management and other personnel, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with accounting principles generally accepted in the United States and include those policies and procedures that:

(1) Pertain to the maintenance of records that in reasonable detail accurately and fairly reflect our transactions and the dispositions of our assets;

(2) Provide reasonable assurance that our transactions are recorded as necessary to permit preparation of financial statements in accordance with accounting principles generally accepted in the United States, and that our receipts and expenditures are being made only in accordance with authorizations of our management and Board of Directors; and

(3) Provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of our assets that could have a material effect on our financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Therefore, even those systems determined to be effective can provide only reasonable assurance with respect to financial statement preparation and presentation.

Under the supervision and with the participation of our management, including our principal executive officer and principal financial officer, we assessed the effectiveness of our internal control over financial reporting as of December 31, 2011, using the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission in Internal Control - Integrated Framework. Based on that evaluation, our principal executive officer and principal financial officer concluded that our internal control over financial reporting were not effective as of December 31, 2011 because of the identification of a

material weakness relating to our review of the completeness and accuracy of the information used to value the postretirement benefit obligations of the Union VEBA.

As discussed in this Report, although (1) our only financial obligation to the Union VEBA is to pay to the Union VEBA an annual variable contribution that does not depend on the funding status of the Union VEBA and to pay to the Union VEBA 50% of its administrative expenses, up to $250,000 per year, (2) the Union VEBA assets and liabilities have no impact on our liquidity or cash flow and (3) we have no control over the plan assets or the benefits provided by the Union VEBA, we are required to account for the Union VEBA's net periodic postretirement benefit costs and record any difference between the Union VEBA assets and the Union VEBA's accumulated postretirement benefit obligation in our financial statements. To determine the value and develop appropriate assumptions for the valuation of the Union VEBA assets and obligations required for this treatment, we must obtain from the Union VEBA administrators, on an annual basis, information regarding the Union VEBA assets, Union VEBA benefit structures, Union VEBA plan participants and Union VEBA participant coverage elections. We have identified that, in certain circumstances, the information and assumptions we used for the valuation of the Union VEBA's postretirement benefit obligations did not accurately reflect the Union VEBA benefit structure, plan participants or participant coverage election.

Deloitte & Touche LLP, the independent registered public accounting firm that audited our consolidated financial statements for the year ended December 31, 2011 included in Item 8. “Financial Statements and Supplementary Data” of this Report, has issued an audit report on the effectiveness of our internal control over financial reporting.

Changes in Internal Controls Over Financial Reporting. We had no changes in our internal control over financial reporting during our most recently completed fiscal quarter that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

INDEX OF EXHIBITS

Exhibit Number	Description
*31.1	Certification of Jack A. Hockema pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
*31.2	Certification of Daniel J. Rinkenberger pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
*32.1	Certification of Jack A. Hockema pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
*32.2	Certification of Daniel J. Rinkenberger pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.

_____________________________

* Filed herewith.

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

KAISER ALUMINUM CORPORATION
	/s/ Jack A. Hockema
	Jack A. Hockema
	President and Chief Executive Officer

Date: February 20, 2013

EX-31.1

Exhibit 31.1

CERTIFICATION PURSUANT TO SECTION 302

OF THE SARBANES-OXLEY ACT OF 2002

I, Jack A. Hockema, certify that:

1. I have reviewed this report on Form 10-K/A of Kaiser Aluminum Corporation;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

(a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

(b) Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

(c) Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

(d) Disclosed in this report any changes in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

(a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

(b) Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

/s/ Jack A. Hockema

Jack A. Hockema

Chief Executive Officer

Date: February 20, 2013

A signed original of this written statement required by Section 302 has been provided to Kaiser Aluminum Corporation and will be retained by Kaiser Aluminum Corporation and furnished to the Securities and Exchange Commission or its staff upon request.

EX-31.2

Exhibit 31.2

CERTIFICATION PURSUANT TO SECTION 302

OF THE SARBANES-OXLEY ACT OF 2002

I, Daniel J. Rinkenberger, certify that:

1. I have reviewed this report on Form 10-K/A of Kaiser Aluminum Corporation;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

(a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

(b) Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

(c) Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

(d) Disclosed in this report any changes in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

(a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

(b) Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

/s/ Daniel J. Rinkenberger

Daniel J. Rinkenberger

Principal Financial Officer

Date: February 20, 2013

A signed original of this written statement required by Section 302 has been provided to Kaiser Aluminum Corporation and will be retained by Kaiser Aluminum Corporation and furnished to the Securities and Exchange Commission or its staff upon request.

EX-32.1

Exhibit 32.1

CERTIFICATION PURSUANT TO

18 U.S.C. 1350

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

February 20, 2013

In connection with the Annual Report on Form 10-K/A by Kaiser Aluminum Corporation, a Delaware corporation (the “Company”), for the year ended December 31, 2011 (the “Report”), as filed on the date hereof with the Securities and Exchange Commission, the undersigned, Jack A. Hockema, Chief Executive Officer of the Company, does hereby certify, pursuant to 18 U.S.C. 1350 as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to such officer’s knowledge:

(1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)); and

(2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company as of the dates and for the periods expressed in the Report.

IN WITNESS WHEREOF, the undersigned has executed this certification as of the date first above written.

/s/ Jack A. Hockema

Jack A. Hockema

Chief Executive Officer

A signed original of this written statement required by Section 906 has been provided to Kaiser Aluminum Corporation and will be retained by Kaiser Aluminum Corporation and furnished to the Securities and Exchange Commission or its staff upon request.

EX-32.2

Exhibit 32.2

CERTIFICATION PURSUANT TO

18 U.S.C. 1350

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

February 20, 2013

In connection with the Annual Report on Form 10-K/A by Kaiser Aluminum Corporation, a Delaware corporation (the “Company”), for the year ended December 31, 2011 (the “Report”), as filed on the date hereof with the Securities and Exchange Commission, the undersigned, Daniel J. Rinkenberger, Principal Financial Officer of the Company, does hereby certify, pursuant to 18 U.S.C. 1350 as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to such officer’s knowledge:

(1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)); and

(2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company as of the dates and for the periods expressed in the Report.

IN WITNESS WHEREOF, the undersigned has executed this certification as of the date first above written.

/s/ Daniel J. Rinkenberger

Daniel J. Rinkenberger

Principal Financial Officer

A signed original of this written statement required by Section 906 has been provided to Kaiser Aluminum Corporation and will be retained by Kaiser Aluminum Corporation and furnished to the Securities and Exchange Commission or its staff upon request.