Hours after the federal government filed an antitrust lawsuit against Humana’s proposed sale to Aetna, Humana announced it wouldn’t offer plans on Affordable Care Act exchanges in several states 2017.

“The company has also notified relevant DOIs of its intent to discontinue certain on-exchange Individual products across a number of geographies for 2017 and exit substantially all Affordable Care Act (ACA) compliant off-exchange Individual markets,” Humana said in its new earnings guidance report. “As a result, the company’s 2017 geographic presence for its Individual offerings is expected to cover no more than 156 counties across 11 states, down from 1,351 counties across 19 states in 2016.”

Humana had first said in May it would leave exchanges after reporting a 21 percent decline in enrollment in marketplace plans. In contrast, its proposed buyer, Aetna, has indicated it may expand its exchange offerings in 2017.

Opponents of the Affordable Care Act have pointed to departures of major insurers like Humana to back up arguments the law isn’t working. Sen. Ben Sasse, R-Neb., told POLITICO after the announcement: “This doesn’t look like a market—it looks like a death spiral.”

Other health experts have disagreed. UCLA Center for Health Policy Research Director Gerald Kominski, PhD, told HealthExec in June argued insurer departures aren’t signs of a death spiral, but “lobbying for continuation of reinsurance payments,” a program which is set to expire after 2016.