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.

Read: Theranos executive to depart amid regulatory probes

The company has told the Centers for Medicare and Medicaid Services that it has issued tens of thousands of corrected blood-test reports to doctors and patients, voiding some results and revising others, according to the person familiar with the matter.

That means some patients received erroneous results that might have thrown off health decisions made with their doctors.

The corrected reports include the voided Edison results and many tests run on traditional laboratory machines, the person said.

Also read: Regulators propose banning Theranos founder for at least two years

Several physician practices in the Phoenix area confirmed receiving corrected test reports from Theranos in recent weeks.

The move is part of Theranos’s attempt to persuade the agency not to impose stiff sanctions it threatened in the aftermath of its inspection of the company’s Newark, Calif., laboratory. The voided and revised test results are one of the most dramatic steps yet taken by Theranos.