The lawsuit filed Wednesday was the result of The Queen's Health Systems plan to directly bill Kaiser for members' emergency medical services beginning May 31, News organizations reported Thursday.
Kaiser has been unable since 2017 to reach an agreement to renew an emergency services contract with the nonprofit health care organization that expired May 30.
Kaiser members would be responsible for claims not reimbursed 100% by the health plan, Queen's Chief Financial Officer Michel Riccioni said in a June 3 letter.
Queen's would not notify or seek clearance from Kaiser for services provided to members, who would be billed for any claim not reimbursed by Kaiser, Riccioni said.
While the Queen's system is no longer part of the Kaiser network, Queen's facilities by law must treat Kaiser members requiring emergency care.
"While we do not comment on pending litigation, we can say that we will continue to ensure all patients who seek our help, regardless of insurance coverage, receive the highest quality of care," said Queen's spokeswoman Minna Sugimoto.
The California-based health maintenance organization called the change "unfair billing practices" that its members are "not legally obligated to pay."
"We cannot agree to QHS demands for unreasonable rate increases," said Kaiser spokeswoman Laura Lott. "Such payments are unsustainable and would greatly increase medical inflation and escalate the overall cost of care for all Hawaii residents."