Theranos Inc. has told federal health regulators that the company voided two years of results from its Edison blood-testing devices, according to a person familiar with the matter.

The Edison machines were touted as revolutionary and were the main basis for the $9 billion valuation attained by the Palo Alto, Calif., company in a funding round in 2014. But Theranos has now told regulators that it threw out all Edison test results from 2014 and 2015.

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