The Wall Street Journal reported this week that Safeway is negotiating to dissolve an unannounced partnership with Theranos — the controversial blood testing company that made Stanford dropout Elizabeth Holmes into a celebrity billionaire — following questions by the supermarket chain's executives about the accuracy of the finger-prick tests that were the key component of the deal.

The Journal said the $350 million partnership, which has been dormant for about a year, had been imagined to be an important part of the grocery chain's push into the wellness market and that it had built clinics in 800 stores that were supposed to offer Theranos blood tests. However, after Theranos missed some deadlines and questions arose about the accuracy of the company's tests given to employees at Safeway's Pleasanton, Calif., headquarters, the deal was put on hold.

The Journal reported that one Safeway executive "worried that Theranos’s finger-prick process was still a work in progress." He said he noticed that Theranos often drew the same person's blood twice: first with a finger prick and then with the traditional method of a needle in the arm. The company also became concerned after one employee got a high result from a Theranos test for a prostate-specific antigen, suggesting that individual may have prostate cancer, but a retest by another lab came back normal.

A Safeway spokesman declined to comment to the Journal about the claims as did Thernos except to say the that the questions and information presented "are inaccurate and defamatory.”

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