The Washington state insurance commissioner gets to sign off on the deal.

Kaiser Permanente has announced plans to acquire Group Health Cooperative, a Seattle-based nonprofit insurer that has about 600,000 members.

Bernard Tyson, chairman of the Kaiser Foundation Health Plan and Hospitals, said the Group Health deal is a natural fit for his company.

Steve Tarnoff, president of Group Health Physicians, said Group Health’s board fully supports the new direction the company is taking and believes joining with Kaiser will reinforce the company’s focus on providing the best possible care.

The two carriers have had reciprocity agreements in place for years.

Both organizations were founded in the mid-1940s, and they have similar models for providing insurance and delivering care. The main difference is that Kaiser, with about 10 million members, is a much bigger company.

Kaiser is a major player in the Patient Protection and Affordable Care Act (PPACA) public exchange system. In California, it has about 260,000 exchange plan enrollees.

The deal is subject to approval by Group Health enrollees and by the Washington state insurance commissioner commissioner.

See also: Washington delays vote on exchange plans again

Group Health was one of the inspirations for the drafters of the PPACA nonprofit, member-owned PPACA Consumer Operated and Oriented Plan (CO-OP) program provisions, but it has no relationship with the PPACA CO-OP program.

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