The companies that have fared best so far are those that have kept the tightest control over their costs, by working closely with low-cost providers or a limited group of hospitals and doctors. Federal officials have said they would tweak those formulas. Insurers did not receive all the payments they were due under one of the lawвЂ™s provisions, and another provision, meant to even out the risk among companies to protect those that enroll sicker individuals, has been described as flawed by many health care experts. The troubles in the individual market also underscore how some of the lawвЂ™s provisions meant to protect the insurers have not worked as well as desired. The dearth of profits from the individual markets, though, show how challenging it is to make insurance affordable when it is not subsidized by the government or an employer.

Over all, insurance companies continue to make profits. It lost $92 million in the state last year and another $39 million in the first three months of 2016. But for every dollar of premium Oscar collects in New York, the company is losing 15 cents. And some of its efforts with technology have been successful. Oscar has attracted 135,000 customers, about half of them in New York State. And its struggles highlight a critical question about the act: Can insurance companies run a viable business in the individual market? These days, though, Oscar is more of a case study in how brutally tough it is to keep a business above water in the state marketplaces created under the Affordable Care Act. вЂњWeвЂ™re trying to build something thatвЂ™s going to turn the industry on its head,вЂќ Joshua Kushner, one of the companyвЂ™s founders, said in 2014, as Oscar began to enroll its first customers. Started in 2012, just in time to offer plans to people buying insurance under the new federal health care law, the business promised to use technology to push less costly care and more consumer-friendly coverage. Oscar Health was going to be a new kind of insurance company.

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