BENTONVILLE, Ark.—Walmart (NYSE: WMT) is in the early stages of talks to buy health insurer Humana (NYSE: HUM), according to reports in The Wall Street Journal and other news media on Friday. The reports didn't disclose terms for the deal. The acquisition would be the latest in a series of high profile deals that could reshape the health care industry, including CVS Health’s (NYSE: CVS) planned acquisition of Aetna (NYSE: AET). The acquisition was overwhelmingly approved by Aetna shareholders last month, but may face opposition from federal regulators over antitrust and consumer protection issues.

In 2017, Humana and Aetna mutually agreed to call off their planned merger after the Justice Department and a federal court took steps to block the proposed deal, as VMAIL reported.

Walmart market capitalization is $263 billion. The retailer posted $13.6 billion in net income in 2017 on revenue of $485.1 billion.

Walmart is the third largest U.S. optical retailers. Walmart’s optical business generated sales of $1.7 billion in sales in 2016, according to Vision Monday’s 2017 Top 50 Optical Retailers Report. It operates 3,575 units, including 3,000 Walmart Vision Centers and 575 Sam’s Optical Club outlets; National Vision operates additional Walmart Vision Centers.

Humana's market value is $37 billion. In 2017, the company reported net income of $2.4 billion on revenue of $53.8 billion. Humana’s vision care insurance business generated $2.2 billion in revenue in 2017.