UnitedHealth Group (UNH)

EXPLANATORY NOTE

We are filing this Amendment No. 1 on Form 10-K/A (the “Amendment”) to UnitedHealth Group Incorporated’s (the “Company”) Annual Report on Form 10-K for the year ended December 31, 2008, as filed with the Securities and Exchange Commission on February 11, 2009 (the “Original Filing”), solely to correct a typographical error contained in Note (a) to the “Selected Financial Data” table regarding the Company’s total 2008 revenue generated under the Medicare Part D drug insurance coverage program. The previously reported amount of revenue for 2008 under this program was $4.6 billion and the correct amount was $5.8 billion.

Except as described above, no other changes have been made to the Original Filing, and this Amendment does not otherwise amend, update or change the financial statements or disclosures in the Original Filing.

EXPLANATORY NOTE

In this Form 10-K, UnitedHealth Group Incorporated (“UnitedHealth Group” or the “Company”) is restating its Consolidated Balance Sheet as of December 31, 2005, and the related Consolidated Statements of Operations, Changes in Shareholders’ Equity and Cash Flows for each of the fiscal years ended December 31, 2005 and December 31, 2004 and quarterly financial data for the quarter ended December 31, 2005.

This Form 10-K also reflects the restatement of “Selected Financial Data” in Item 6 for the fiscal years ended December 31, 2005, 2004, 2003 and 2002, and the amendment of “Management’s Discussion and Analysis of Financial Condition and Results of Operations” presented in the Company’s Form 10-K for the fiscal year ended December 31, 2005 as it related to the fiscal years ended December 31, 2005 and December 31, 2004.

Immediately prior to the filing of this Form 10-K, the Company filed an amended quarterly report on Form 10-Q/A for the quarter ended March 31, 2006 and quarterly reports on Form 10-Q for the quarters ended June 30, 2006 and September 30, 2006. These Forms 10-Q/A and 10-Q contain restated financial information for the first three fiscal quarters of 2005 and the quarter ended March 31, 2006.

Previously filed annual reports on Form 10-K and quarterly reports on Form 10-Q (other than for the quarter ended March 31, 2006, which has been amended by the Form 10-Q/A) have not been amended and should not be relied upon.

EXPLANATORY NOTE

In this Form 10-Q, UnitedHealth Group Incorporated (“UnitedHealth Group” or the “Company”) is restating its Condensed Consolidated Balance Sheet as of December 31, 2005 and the Condensed Consolidated Statements of Operations and Cash Flows for the three- and nine-month periods ended September 30, 2005. This Form 10-Q also reflects the amendment of “Management’s Discussion and Analysis of Financial Condition and Results of Operations” presented in the Company’s Form 10-Q for the quarter ended September 30, 2005 as it related to the period ended September 30, 2005.

Immediately prior to the filing of this Form 10-Q, the Company filed an amended quarterly report on Form 10-Q/A for the quarter ended March 31, 2006 (the “Form 10-Q/A”) and a quarterly report on Form 10-Q for the quarter ended June 30, 2006. The Form 10-Q/A contains restated financial information for the periods ended March 31, 2006 and March 31, 2005, and the Form 10-Q for the quarter ended June 30, 2006 contains restated financial information for the period ended June 30, 2005.

Immediately after the filing of this Form 10-Q, the Company will file an annual report on Form 10-K for the year ended December 31, 2006 (the “2006 Form 10-K”). In the 2006 Form 10-K, the Company will restate its Consolidated Balance Sheet as of December 31, 2005, and the related Consolidated Statements of Operations, Changes in Shareholders’ Equity and Cash Flows for each of the fiscal years ended December 31, 2005 and December 31, 2004 and quarterly financial data for the quarter ended December 31, 2005. The 2006 Form 10-K will also reflect the restatement of “Selected Financial Data” in Item 6 for the fiscal years ended December 31, 2005, 2004, 2003 and 2002, and the amendment of “Management’s Discussion and Analysis of Financial Condition and Results of Operations” presented in the Company’s Form 10-K for the fiscal year ended December 31, 2005 as it related to the fiscal years ended December 31, 2005 and December 31, 2004.

Previously filed annual reports on Form 10-K and previously filed quarterly reports on Form 10-Q (other than for the quarters ended June 30, 2006 and March, 31, 2006, the later of which has been amended by the Form 10-Q/A) have not been amended and should not be relied upon.

EXPLANATORY NOTE

In this Form 10-Q, UnitedHealth Group Incorporated (“UnitedHealth Group” or the “Company”) is restating its Condensed Consolidated Balance Sheet as of December 31, 2005 and the Condensed Consolidated Statements of Operations and Cash Flows for the three and six months ended June 30, 2005. This Form 10-Q also reflects the amendment of “Management’s Discussion and Analysis of Financial Condition and Results of Operations” presented in the Company’s Form 10-Q for the quarter ended June 30, 2005 as it related to the period ended June 30, 2005.

Immediately prior to the filing of this Form 10-Q, the Company filed an amended quarterly report on Form 10-Q/A for the quarter ended March 31, 2006 (the “Form 10-Q/A”), and immediately after the filing of this Form 10-Q, the Company will file a quarterly report on Form 10-Q for the quarter ended September 30, 2006 and an annual report on Form 10-K for the year ended December 31, 2006 (the “2006 Form 10-K”). The Form 10-Q/A contains restated financial information for the periods ended March 31, 2005 and March 31, 2006; the Form 10-Q for the quarter ended September 30, 2006 will contain restated financial information for the period ended September 30, 2005. In the 2006 Form 10-K, the Company will restate its Consolidated Balance Sheet as of December 31, 2005, and the related Consolidated Statements of Operations, Changes in Shareholders’ Equity and Cash Flows for each of the fiscal years ended December 31, 2005 and December 31, 2004 and quarterly financial data for the quarter ended December 31, 2005. The 2006 Form 10-K will also reflect the restatement of “Selected Financial Data” in Item 6 for the fiscal years ended December 31, 2005, 2004, 2003 and 2002, and the amendment of “Management’s Discussion and Analysis of Financial Condition and Results of Operations” presented in the Company’s Form 10-K for the fiscal year ended December 31, 2005 as it related to the fiscal years ended December 31, 2005 and December 31, 2004.

Previously filed annual reports on Form 10-K and quarterly reports on Form 10-Q (other than for the quarter ended March 31, 2006, which has been amended by the Form 10-Q/A) have not been amended and should not be relied upon.

EXPLANATORY NOTE

In this Amendment No. 1 on Form 10-Q/A to its quarterly report on Form 10-Q for the quarter ended March 31, 2006, UnitedHealth Group Incorporated (“UnitedHealth Group” or the “Company”) is restating its Condensed Consolidated Balance Sheets as of March 31, 2006 and December 31, 2005 and the related Condensed Consolidated Statements of Operations and Cash Flows for the quarters ended March 31, 2006 and March 31, 2005 and is amending its “Management’s Discussion and Analysis of Financial Condition and Results of Operations” for these periods. This Form 10-Q/A generally does not reflect events that have occurred after May 10, 2006, or modify or update the disclosures originally presented in the Form 10-Q, except to reflect the effects of the restatement, to reflect changes in the Company’s evaluation of controls and procedures, to update the risks the Company faces as a result of its historic stock option practices, and to clarify certain disclosures.

Immediately after the filing of this Form 10-Q/A, the Company will file quarterly reports on Form 10-Q for the quarters ended June 30, 2006 and September 30, 2006, and an annual report on Form 10-K for the year ended December 31, 2006 (the “2006 Form 10-K”). The two Form 10-Qs will contain restated financial information for the periods ended June 30, 2005 and September 30, 2005. In the 2006 Form 10-K, the Company will restate its Consolidated Balance Sheet as of December 31, 2005, and the related Consolidated Statements of Operations, Changes in Shareholders’ Equity and Cash Flows for each of the fiscal years ended December 31, 2005 and December 31, 2004 and quarterly financial data for the quarter ended December 31, 2005. The 2006 Form 10-K will also reflect the restatement of “Selected Financial Data” in Item 6 for the fiscal years ended December 31, 2005, 2004, 2003 and 2002, and the amendment of “Management’s Discussion and Analysis of Financial Condition and Results of Operations” presented in the Company’s Form 10-K for the fiscal year ended December 31, 2005 as it related to the fiscal years ended December 31, 2005 and December 31, 2004.

Previously filed annual reports on Form 10-K and quarterly reports on Form 10-Q (other than for the quarter ended March 31, 2006, which has been amended by this Form 10-Q/A) have not been amended and should not be relied upon.