A news summary, focused on big employers; updated 6:12 p.m.

Quarrels have broken out behind the scenes of Anthem’s proposed acquisition of Cigna, as the health insurers seek regulatory approval for their landmark $48 billion deal, according to a series of letters reviewed by The Wall Street Journal. “People on both sides say the squabbles could delay or derail antitrust approvals, which are typically harder to obtain if both parties aren’t in sync,” the Journal is reporting today.

The deal was announced July 24, three weeks after Aetna and Humana announced their own planned $34 billion tie-up, as big insurers sought scale and efficiency in a shifting U.S. health care industry. The Anthem-Cigna dissension suggests their proposal may fall behind in the regulatory review,  worrisome because it’s “thought to have better odds if reviewed alongside Aetna-Humana,” the Journal says.

On Friday, Aetna CEO Mark Bertolini said he expected his company’s purchase of Humana would close during the second half of the year. He also said he couldn’t rule out the possibility Aetna might move its headquarters from its historic Hartford home once the deal is complete.

In other news, new federal overtime regulations could force employers to boost the pay of about 149,000 Kentuckians, although mostly at small and mid-sized companies. Starting in December, salaried employees earning $47,476 or less annually must be paid time-and-a-half for working more than 40 hours in a week; that’s twice the current level (Courier-Journal).