The biggest names in health insurance like UnitedHealth Group (UNH), Humana (HUM), Cigna (CI), Wellpoint (WLP) and Aetna (AET) and Blue Cross and Blue Shield plans across the country are contracting with ACOs.

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Already, private insurance companies like UnitedHealth Group (UNH), Humana (HUM), Aetna (AET) and most Blue Cross and Blue Shield plans are making bundled payments to groups of doctors and hospitals.

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They have their benefits provided by large and medium-sized employers and administered by health plans that include UnitedHealth Group (UNH), Humana (HUM), Aetna (AET), Cigna (CI) and Blue Cross and Blue Shield plans.

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