Several large publicly traded managed care companies saw sharp declines in their market capitalization in the third quarter.
UnitedHealth Group Inc., which continues to have the largest market cap of any U.S. insurance underwriter, saw its value shrink by 11.2% in the period. Its stock tumbled 10.9% to $217.32 as of Sept. 30 from $244.01 at June 30.
Property and casualty giant Chubb Ltd. jumped over Anthem Inc. to the No. 2 spot in the rankings as its market cap increased sequentially by 9.4% to $73.58 billion, while Anthem's slumped to $61.42 billion.
Centene Corp. fell two positions in the rankings after shedding 17.5% of its market cap to $17.89 billion. Humana Inc. and Cigna Corp. also logged declines in their market caps, though those losses were more modest. Humana's slipped 3.6% to $34.54 billion, while Cigna's dropped 4.0% to $57.32 billion.
The total return for the S&P 500 Insurance index, which takes into account all public U.S.-headquartered insurance underwriters, rose 1.3% in the quarter, while the broader S&P 500 index climbed 1.7%.

