Adam Rosendorff

Adam Rosendorff testified for the prosecution over several trial days about his work as Theranos's clinical laboratory director during 2013 and 2014. He said he initially supported the company's fingerstick-testing concept but became concerned that launch and business priorities were overtaking laboratory quality and patient care.

His testimony addressed incomplete validation, quality-control failures, inconsistent device results, physician complaints, held or voided results, proficiency testing, and inspection preparation. He described problems involving HCG, HDL, bicarbonate, vitamin D, electrolytes, and other testing, and said some anomalies continued after attempted fixes. Rosendorff testified that he warned Holmes and other managers, encountered constraints on proposed disclosures and corrective measures, sought removal from the laboratory-director role, and later contacted an attorney and a reporter because he believed professional and ethical obligations required him to raise his concerns.

On cross-examination, the defense emphasized Rosendorff's regulatory duties, validation approvals, authority to stop or redirect testing, prior testimony, government contacts, limited-immunity agreements, and the circumstances of his departure. He agreed that he approved multiple Edison assay validations, would not have signed reports he considered unsupported, and was never instructed by Holmes to report an inaccurate result. He also acknowledged responsive investigations, conventional-instrument proficiency testing, relatively minor inspection deficiencies, and qualifications or corrections to parts of his testimony. Rosendorff maintained that initial validation did not resolve later performance problems and that management control of resources and operations limited his practical authority despite his formal responsibility.

On redirect, Rosendorff clarified that his criticism of proficiency testing concerned Theranos-developed and modified methods rather than unmodified instruments, and he said fingerstick and quality-control problems persisted after attempted remedies. He denied that financial or employment considerations drove his account and attributed his departure to patient care, professional responsibility, and concern for his reputation. On recross, he acknowledged awareness of HCG quality-control work and limits in his earlier complaint testimony while continuing to qualify broader characterizations.