UnitedHealth Group (UNH)

Report of Management

The management of UnitedHealth Group is responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) under the Securities Exchange Act of 1934. The company’s internal control system is designed to provide reasonable assurance to our management and board of directors regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. The company’s internal control over financial reporting includes those policies and procedures that:

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Management assessed the effectiveness of the company’s internal control over financial reporting as of December 31, 2005. In making this assessment, we used the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) in Internal Control—Integrated Framework. Based on our assessment and those criteria, we believe that, as of December 31, 2005, the company maintained effective internal control over financial reporting.

Management excluded from its assessment of the effectiveness of the Company’s internal control over financial reporting the internal controls of PacifiCare Health Systems, Inc. (PacifiCare) which was acquired by the Company on December 20, 2005, and is included in the Company’s consolidated financial statements for the period from that date through yearend. Such exclusion was in accordance with Securities and Exchange Commission guidance that an assessment of a recently acquired business may be omitted in management’s report on internal controls over financial reporting in the year of acquisition. Total assets and total liabilities of

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PacifiCare represented approximately 29% and 13%, respectively, of the Company’s consolidated assets and liabilities as of December 31, 2005, and less than 1% of consolidated revenues and operating income for the year then ended.

Changes to certain processes, information technology systems, and other components of Internal Control resulting from the acquisition of PacifiCare may occur and will be evaluated by management as such integration activities are implemented. Other than the impact of the acquisition, there were no changes in Internal Control that have materially affected, or are reasonably likely to materially affect, the Company’s Internal Control during the year ended December 31, 2005.

The company’s independent registered public accounting firm has audited management’s assessment of the effectiveness of the company’s internal control over financial reporting as of December 31, 2005, as stated in the Report of Independent Registered Public Accounting Firm, appearing under Item 9A, which expresses unqualified opinions on management’s assessment and on the effectiveness of the company’s internal controls over financial reporting as of December 31, 2005.

February 24, 2006

/s/    WILLIAM W. MCGUIRE, MD

Report of Management

The management of UnitedHealth Group is responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) under the Securities Exchange Act of 1934. The company’s internal control system is designed to provide reasonable assurance to our management and board of directors regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. The company’s internal control over financial reporting includes those policies and procedures that:

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Management assessed the effectiveness of the company’s internal control over financial reporting as of December 31, 2004. In making this assessment, we used the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) in Internal Control—Integrated Framework. Based on our assessment and those criteria, we believe that, as of December 31, 2004, the company maintained effective internal control over financial reporting.

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The company’s independent registered public accounting firm has audited management’s assessment of the effectiveness of the company’s internal control over financial reporting as of December 31, 2004, as stated in the Report of Independent Registered Public Accounting Firm, appearing under Item 9A, which expresses unqualified opinions on management’s assessment and on the effectiveness of the company’s internal controls over financial reporting as of December 31, 2004.

February 28, 2005

/S/    WILLIAM W. MCGUIRE, MD