Theranos Inc., a high-profile Silicon Valley medical testing company valued at $9 billion, turned heads with assertions that it can perform a multitude of medical tests with just drops of blood pricked from fingers. But it received unwelcome attention earlier this month when a Wall Street Journal article called into question the accuracy of the company’s testing technology.

Tuesday, the Food and Drug Administration released two inspection documents [PDF] that validate some of the issues raised in the article. In the documents, the agency called the company’s tiny blood vials “uncleared medical devices,” noted quality assurance issues, and found that the company did not properly investigate customer complaints.

In an e-mailed statement to the WSJ, Theranos general counsel Heather King said the company has “addressed and corrected” all the problems flagged by FDA inspectors.

The inspection, which spanned Aug. 25 to Sept. 16, found 14 “observations,” including that the company's “nanotainer”—a wee vial for collecting blood­—was an uncleared medical device. This backs information in the initial WSJ article, which reported that the company had stopped using the vials for all but one test following pressure from the FDA. The one test using the vial is a herpes test that had received FDA approval this summer.

Neglected customer complaints cited in the document include reports that the nanotainers were “too opaque to be able to see clotting clearly.”

Monday, Theranos CEO Elizabeth Holmes said the beleaguered company would publish data that validate its blood tests. So far in contrast to standard practice, the company has not published any data on its tests in peer-reviewed journals.