By Jonathan D. Rockoff And Dana Cimilluca 

Anthem Inc. boosted its takeover offer for Cigna Corp. and is going public with the bid after the two sides failed to reach agreement, the latest move in a frenzy of attempted mergers among health insurers.

Anthem in a statement said it has offered $184 a share for Cigna. That equates to about $47.5 billion for all the company's stock that was recently outstanding. Anthem is making the cash-and-stock offer public in an effort to put pressure on Cigna through its shareholders, according to a person familiar with the matter.

Cigna had no comment Saturday afternoon.

Anthem's pursuit of Cigna comes as Cigna and others are eyeing Humana Inc., which has put itself up for sale. Aetna Inc. in the last few days made a takeover proposal to Humana. It isn't clear how much Aetna indicated it would pay.

UnitedHealth Group Inc., meanwhile, recently made a takeover approach to Aetna.

It isn't clear what, if any, Aetna's response was.

The five big managed-care companies are jockeying for deals that will enable them to get more efficient and better respond to changes in the health care landscape in the U.S. brought on by the Affordable Care Act and other developments.

Analysts says it is likely regulators will only allow one or two such combinations.

Anthem, which is based in Indianapolis and until last year was known as WellPoint, made a number of bids for Cigna privately in June, according to a letter Anthem Chief Executive Joseph Swedish sent to Cigna's board Saturday. The letter was released by Anthem. Among other things, it details disagreement the two sides have over the role Cigna CEO David Cordani would play in a combined company. He wants to be CEO, if not immediately then after a period of time, which Anthem refuses to guarantee.

The Journal had reported earlier this week that Anthem was pursuing Cigna, and had bid about $175 a share, which was rejected, and that Mr. Cordani's potential role was a sticking point.

Anthem's bid consists of about 31% of its own shares and the rest in cash. About 76% of the combined company would be owned by Anthem shareholders, while Cigna investors would own the rest, according to the latest proposal.

Cigna is seeking a nearly 50-50 split of directors on a combined company's board, Anthem said. Cigna also pushed for an offer price split evenly between cash and stock, according to Anthem.

Anthem, which said it has been in negotiations with Cigna since Aug. 2014, bemoaned what it called its rival's refusal to "reasonably negotiate." It said the governance demands Cigna is making are excessive, given the rich premium Anthem says it is offering.

"We were stunned that the Cigna board continues to insist on a guaranteed CEO position for Mr. Cordani over choosing to allow its stockholders to realize the significant premium being offered," the Anthem letter reads.

Anthem said it submitted four bids in June, the most recent, of $184 a share, on Thursday.

Shares of Cigna, which is based in Bloomfield, Conn., closed Friday at $155.30, giving the company a market value of $40 billion.

A combination would create a big player in the commercial health-insurance business, with strong positions among individual, small-business and big-employer clients. It would vault Anthem, the nation's second-largest health insurer, closer to UnitedHealth in size. Cigna's revenue last year totaled $34.9 billion, while Anthem's was $73.9 billion. UnitedHealth had revenue of $130.5 billion, including its health-services arm, Optum, while Aetna's was $58 billion and Humana's was $48.5 billion.

Anthem is a huge player in the individual and small-group markets in the 14 states where it holds the rights to be the Blue Cross and Blue Shield insurer. It also has a strong role among national employers. Cigna, meantime, focuses closely on self-insured commercial business and has a significant and growing position overseas.

A merged company would have a bigger presence in the fast-growing Medicare Advantage market, an area where both companies have lagged behind competitors. Together, Anthem and Cigna would have more than a million Medicare members. Anthem also has a major presence in Medicaid.

An attempt to seal an Anthem-Cigna merger could be complicated by Anthem's role as a Blue Cross and Blue Shield insurer, however.

The Blue Cross and Blue Shield plans hold geographic rights to use the Blue brand only in a particular area, and they also agree to certain limits on their non-Blue business. It is unclear how Anthem would manage the legacy Cigna business in states where another insurer is the local Blue. In its letter, Anthem said it was "confident in its ability to obtain regulatory approvals" and this "includes matters related to the Blue Cross Blue Shield Association."

Humana has held sale talks with companies including Cigna and Aetna, people familiar with the matter have said. Humana, based in Louisville, Ky., gets the bulk of its revenue from its business administering the private version of the federal Medicare program.

The company is seen as a prize because of its powerful Medicare franchise, which is growing rapidly as baby boomers age into eligibility and opt for these plans, known as Medicare Advantage.

Aetna has been viewed by some industry analysts as the most likely acquirer of Humana, and executives at Aetna have spoken publicly about their interest in acquisitions.

Anna Wilde Mathews contributed to this article.

Write to Jonathan D. Rockoff at Jonathan.Rockoff@wsj.com, Dana Cimilluca at dana.cimilluca@wsj.com, Dana Mattioli at dana.mattioli@wsj.com and Liz Hoffman at liz.hoffman@wsj.com

Access Investor Kit for Aetna, Inc.

Visit http://www.companyspotlight.com/partner?cp_code=P479&isin=US00817Y1082

Access Investor Kit for Cigna Corp.

Visit http://www.companyspotlight.com/partner?cp_code=P479&isin=US1255091092

Access Investor Kit for Humana, Inc.

Visit http://www.companyspotlight.com/partner?cp_code=P479&isin=US4448591028

Access Investor Kit for UnitedHealth Group, Inc.

Visit http://www.companyspotlight.com/partner?cp_code=P479&isin=US91324P1021

Subscribe to WSJ: http://online.wsj.com?mod=djnwires

Humana (NYSE:HUM)
Historical Stock Chart
From Jun 2024 to Jul 2024 Click Here for more Humana Charts.
Humana (NYSE:HUM)
Historical Stock Chart
From Jul 2023 to Jul 2024 Click Here for more Humana Charts.