Payer

Aetna's roots go back to the 1850s, when Aetna Insurance Company organized an annuity fund to sell life insurance. Since then, Hartford, Conn.-based Aetna has become one of the nation's largest insurance companies, providing insurance to roughly 46 million people.

Activity is bubbling in the healthcare payer market, as rumors of acquisitions are surfacing. One of those payers, among the big five key companies, is UnitedHealthcare.

Bloomfield, Conn.-based Cigna was formed through the combination of INA Corporation and Connecticut General Corporation in 1982. The company has since evolved into one of the "big five" health insurers in the U.S.

UnitedHealth Group has approached Aetna about a takeover deal within the past few days, according toThe Wall Street Journal.

Shares of health insurer Cigna jumped nearly 12 percent Monday after it was reported that Anthem had made two takeover bids for Cigna within the past two weeks, according to a Hartford Courant report.

The following New Jersey hospitals have the highest share of patients who qualify as charity care or Medicaid, according to NJ Spotlight.

Within the past 10 days Anthem has made two takeover bids for Cigna, and Cigna has rejected both of them, according to The Wall Street Journal.

Insurance giant Assurant has announced it will exit the health insurance market by the end of 2016, and it will "begin to wind down its major medical operations" immediately.

Blue Cross and Blue Shield is the oldest and largest payer group in the U.S., consisting of 36 independent, locally operated franchises that collectively make up the Blue Cross Blue Shield Association.

Shares of Humana rose 2.4 percent Monday after the Louisville, Ky.-based health insurer announced it was entering into a so-called "quiet period," according to The Wall Street Journal.