Theranos Inc. allegedly voided 11.3% of all blood-test reports that the Silicon Valley laboratory firm provided to customers of Walgreens stores through a yearslong partnership between the two companies, according to legal papers the drugstore chain filed Tuesday.

Theranos, whose main lab failed an inspection by U.S. regulators earlier this year, told Walgreens in June that it subsequently voided 31,000 test reports provided to the chain’s customers, Walgreens said in the public version of a sealed lawsuit.

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