Vestar Capital Partners has acquired a majority stake in healthcare software provider Quest Analytics. The target’s management, led by co-founders David Hill and John Weis, will keep a minority ownership.

Headquartered in Appleton, Wisconsin, Quest develops healthcare technology for providers and government agencies. Quest’s products helps companies manage their network databases and stay compliant with regulations. Kirkland & Ellis represented Vestar. Brown Gibbons Lang and Foley & Lardner advised Quest.

“Quest’s products and services are critical competitive tools for health plan networks in the current volatile and uncertain healthcare environment,” says Vestar managing director Roger Holstein. “As healthcare costs continue to rise, health plans are narrowing the size of provider networks in order to keep premiums affordable.”

Vestar, headquartered in New York, is a private equity firm that usually invests between $50 million and $200 million in U.S.-based middle market companies. Earlier in 2017, the firm backed foodservice equipment distributor Edward Don & Company.

In other healthcare technology deals, EQT has agreed to acquire a majority stake in healthcare technology provider Certara; Francisco Partners’ eSolutions is purchasing data analytics firm RemitDATA; and New Mountain Capital-backed Ciox Health acquired data service company Arrohealth.