Oscar Insurance Corp., the Silicon Valley-backed health-care startup, continued to lose tens of millions of dollars in the third quarter as the company exits some markets and works to diversify away from of its Obamacare business.

The New York-based company sells health insurance to individuals in new markets set up by the Affordable Care Act. Its attempt to reinvent the insurance business has been marked by large losses — in the third quarter, closely held Oscar lost $45 million in New York, Texas and California, according to filings with regulators. That follows losses of $83 million in those states during the first six months of this year.

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