UNITEDHEALTH GROUP INC

2. Investments

A summary of debt securities by major security type is as follows:

The Company held $4.1 billion and $4.9 billion of equity securities as of March 31, 2024 and December 31, 2023, respectively. The Company’s investments in equity securities primarily consist of venture investments and employee savings plan related investments. Additionally, the Company’s investments included $1.4 billion of equity method investments primarily in operating businesses in the health care sector as of March 31, 2024 and December 31, 2023. The allowance for credit losses on held-to-maturity securities at March 31, 2024 and December 31, 2023 was not material.

The amortized cost and fair value of debt securities as of March 31, 2024, by contractual maturity, were as follows:

The fair value of available-for-sale debt securities with gross unrealized losses by major security type and length of time that individual securities have been in a continuous unrealized loss position were as follows:

The Company’s unrealized losses from debt securities as of March 31, 2024 were generated from approximately 32,000 positions out of a total of 39,000 positions. The Company believes that it will timely collect the principal and interest due on its debt securities that have an amortized cost in excess of fair value. The unrealized losses were primarily caused by interest rate increases and not by unfavorable changes in the credit quality associated with these securities which impacted the Company’s assessment on collectability of principal and interest. At each reporting period, the Company evaluates available-for-sale debt securities for any credit-related impairment when the fair value of the investment is less than its amortized cost. The Company evaluated the expected cash flows, the underlying credit quality and credit ratings of the issuers, noting no significant credit deterioration since purchase. As of March 31, 2024, the Company did not have the intent to sell any of the available-for-sale debt securities in an unrealized loss position. Therefore, the Company believes these losses to be temporary. The allowance for credit losses on available-for-sale debt securities at March 31, 2024 and December 31, 2023 was not material.