Health plans

Aetna

Based in Hartford, Conn., Aetna Inc. is one of the country’s largest health plans. Aetna converted several years ago from offering all types of insurance to focus only on health insurance. Its most recent acquisitions have strengthened its position in the managed Medicaid market and the international health insurance field.

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Blues (single-state)

Independent nonprofit plans with Blue Cross and/or Blue Shield trademarks operate in 28 states. All belong to the BlueCross and BlueShield Assn., but operate under their own licenses. In most states, only one company holds a "Blue" trademark, but in a few, including New York and Pennsylvania, the BlueCross and BlueShield Assn. has granted the licenses by region.

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CareFirst

Based in Owings Mills, Md., CareFirst operates Blue Cross Blue Shield-licensed plans in Maryland, Virginia and Washington, D.C.

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Cigna

Philadelphia-based Cigna Health Care is unusual in mixing its health insurance business with life insurance and other products. Most of its membership is in the Northeast, though it has expanded its geographic base through acquisitions. It also has a significant international health insurance business.

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Coventry

Coventry is one of the smallest of the publicly traded health plans by membership, but it has the highest market share of workers' compensation physician networks.

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HCSC

Headquartered in Chicago, mutually owned Health Care Service Corp controls Blue Cross Blue Shield-licensed plans in four states: Oklahoma, Illinois, New Mexico and Texas.

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Health Net

Based in Woodland Hills, Calif., Health Net is among the smallest of the major, publicly traded health plans. It operates mostly in California, but does have business in other regions.

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Humana

Based in Louisville, Ky., Humana Inc. has significant government presence through its Medicare Advantage and military contracts, with much of its growth over the past decade dependent on Medicare Advantage.

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Kaiser

The country's largest nonprofit health plan, Kaiser Permanente is based in California. It operates hospitals, physician groups and health plans in nine states and in Washington, D.C. It is the largest remaining example of staff-model HMOs and large-scale managed care.

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Premera

Based in Mountlake Terrace, Wash., Premera is an operator of nonprofit Blue Cross Blue Shield-affiliated plans that cover members in Washington, Oregon, Alaska and Arizona.

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Regence

The Regence Group, based in Portland, Ore., operates nonprofit Blue Cross Blue Shield-licensed plans in Washington, Oregon, Idaho and Utah.

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United

UnitedHealth Group, based in Minnetonka, Minn., is one of the largest health plans in the country, with divisions in Medicaid, Medicare, pharmacy, medical research, claims adminstration and data mining, as well as individual and group commercial health insurance.

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Wellmark

Midwestern regional Blues company Wellmark is based in Des Moines, Iowa, and operates Blue Cross Blue Shield-affiliated plans in South Dakota and Iowa. It is a mutually owned company.

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WellPoint

WellPoint draws much of its strength from the Blue Cross Blue Shield name it holds in 14 states, where it runs for-profit plans.

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