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Elizabeth Holmes- Case Archive
personpersonKingshuk DasKingshuk DasPhysician and former Theranos clinical laboratory director who led laboratory remediation work.← All People
WitnessTheranos

Kingshuk Das

Physician and former Theranos clinical laboratory director who led laboratory remediation work.

AppearedFederal Criminal Trial
1,313 lines·30 proceedings·24 mentions

About

Kingshuk Das testified as Theranos's California laboratory director about his response to deficiencies identified after the September 2015 CMS inspection. He described reviewing validation reports, quality-control records, and patient-result distributions, as well as repeatedly discussing the deficiencies, immediate-jeopardy language, and company response with Elizabeth Holmes.

Das identified reported PSA results for female patients, patient results issued after failed quality control, and an assessment finding possible impact across TPS 3.5 testing. He testified that approximately 50,000 to 60,000 Edison tests were marked void, that clinical testing did not resume on Edison 3.5 or another Theranos-manufactured device, and that he did not recommend resuming use because he considered the instruments unsuitable for clinical testing.

Defense questioning challenged the retrospective scope and foundation of Das's review, the methodology used to assess patient impact, and whether voiding was legally required or instead a discretionary corrective measure. On redirect, Das returned to the quality-control evidence and review methodology. On recross, he said quality-control concerns supported the voiding decision in part, acknowledged that counsel prepared two CMS letters he signed, and distinguished his disagreement with one phrase from his acceptance of the related letter overall.

Trial Record (30)

FederalFederal Criminal TrialAug 31, 2021 – Jan 3, 2022Called by prosecution

Kingshuk Das, Theranos's California laboratory director, testified about investigating CMS deficiencies, discussing his findings with Elizabeth Holmes, and recommending that Edison test results be voided. Defense questioning challenged the foundation, methodology, regulatory characterization, and related correspondence behind his review.

Day 4

OpeningOpening Statement by the ProsecutionRobert S. LeachMentioned

Summary

The prosecution alleged that Elizabeth Holmes and Ramesh Balwani defrauded Theranos investors and patients through misrepresentations about the company's technology, partnerships, finances, retail rollout, and test accuracy. It previewed insiders, investors, patients, outside organizations, and records that it expected would support the wire-fraud and conspiracy charges.

Mentioned in this proceeding.

Day 15

Day 23

ProceduralEvidentiary Conference on Tolbert ExhibitsMentioned

Summary

Judge Davila ordered the admission process for Exhibit 5387-D repeated before the jury and heard competing arguments over Tolbert-related notes and a 2016 shareholder communication, leaving their disputed uses unresolved pending testimony and cross-examination.

Mentioned in this proceeding.

Day 28

colloquyCMS Report and Voided-Test Evidence ColloquyMentioned

Summary

The parties disputed the admissibility and scope of the CMS report and Kingshuk Das's anticipated voided-test testimony. The court ordered a written prosecution proffer by midday Monday and scheduled argument for Tuesday morning without deciding admissibility.

Mentioned in this proceeding.

Day 30

ProceduralCMS Evidence and Dr. Das Testimony Hearing3highlightsMentioned

Summary

Outside the jury's presence, counsel disputed how the CMS deficiency report and Dr. Kingshuk Das's testimony could be presented, including hearsay, Rule 403, Rule 407, and expert-testimony limits.

Mentioned in this proceeding.

Highlights (3)

rulingThe court reaffirmed that Dr. Das could testify only as a percipient witness, not as an expert, and said any testimony agreeing with CMS findings would depend on the foundation laid during examination.Open in transcript →
Quote“HE'S NOT GOING TO BE ABLE TO TESTIFY AS AN EXPERT.”— Edward J. DavilaThe court stated the governing limitation on Dr. Das's testimony.Open in transcript →
procedural actionAfter the parties disputed whether voiding test results was legally required or discretionary, the court identified foundational questioning of Dr. Das as the efficient way to address the issue, and the prosecution agreed to that approach.Open in transcript →
DirectKingshuk Das — DirectKingshuk DasRobert S. Leach7highlights323lines spoken

Summary

Kingshuk Das described Theranos's urgent CMS response, Edison quality-control problems, discussions with Elizabeth Holmes, and the decision to void all TPS 3.5 results.

Highlights (7)

Quote“YES. THAT WAS NEARLY THE SOLE RESPONSIBILITY THAT I HAD.”— Kingshuk DasDas described responding to the CMS statement of deficiencies as the dominant responsibility of his new laboratory-director role.Open in transcript →
testimony highlightDas identified the CMS notice's immediate-jeopardy language, explained that it created urgency, and confirmed discussing the need for an urgent response with Holmes.Open in transcript →
testimony highlightDas testified that he used PSA results reported for female patients to illustrate the Edison's propensity for erroneous results to Holmes; he found her alternative explanation implausible.Open in transcript →
Quote“THAT'S NOT ONLY A REGULATORY OBLIGATION BUT A PROFESSIONAL ONE AND AN ETHICAL ONE AS WELL.”— Kingshuk DasDas framed patient-impact assessment as a regulatory, professional, and ethical responsibility of the laboratory director.Open in transcript →
Show all 7 highlights
evidence eventAfter Exhibit 4943 was admitted, Das confirmed that the laboratory reported poor quality-control performance across all tests run on the Edison and expanded its retrospective review to determine how far the poor performance extended.Open in transcript →
testimony highlightDas testified that the laboratory concluded every TPS 3.5 test had possible patient impact, voided all results from the instrument, discussed the rationale with Holmes, and never resumed or recommended resuming testing because he found the instruments unsuitable for clinical use.Open in transcript →
Quote“I FOUND THESE INSTRUMENTS TO BE UNSUITABLE FOR CLINICAL USE.”— Kingshuk DasDas stated his ultimate reason for not recommending resumed clinical testing on the TPS 3.5 instruments.Open in transcript →
DirectKingshuk Das — Direct Examination ResumedKingshuk DasRobert S. Leach4highlights97lines spoken

Summary

Kingshuk Das testified about CMS quality-control findings, patient results reported after failed quality control, and the voiding of approximately 50,000 to 60,000 Edison tests.

Highlights (4)

testimony highlightFollowing a sustained scope objection and rephrasing, Das testified that his investigation found PT INR and Edison patient results reported after failed quality control; the court overruled two subsequent Rule 702 objections.Open in transcript →
Quote“QUALITY CONTROL MUST BE RUN DAILY WHEN PATIENT TEST RESULTS ARE BEING RUN ON ANY ASSAY.”— Kingshuk DasDas stated the laboratory requirement underlying his concern about reporting patient results after unacceptable quality control.Open in transcript →
testimony highlightDas testified that Theranos issued voided corrective reports for approximately 50,000 to 60,000 Edison tests and never resumed testing on Edison 3.5 or another Theranos-manufactured device in the CLIA laboratory.Open in transcript →
Quote“I DON'T KNOW THE EXACT NUMBER, BUT IT WAS APPROXIMATELY 50- TO 60,000.”— Kingshuk DasDas supplied the approximate scale of Edison tests that were voided while expressly acknowledging that he did not know the exact total.Open in transcript →

Day 31

ProceduralLIS Evidence and Door-Opening HearingMentioned2lines spoken

Summary

The parties debated whether a possible missing-LIS argument would open the door to evidence about the system's unavailability, and the defense agreed to provide limited notice by the next afternoon. The government also announced a limited recall of Danise Yam concerning an email.

Mentioned in this proceeding.

CrossKingshuk Das — CrossKingshuk DasLance A. Wade2highlights664lines spoken

Summary

Das said Holmes supported his independent laboratory judgments and remediation, while he maintained that Edison validation failures required voiding the results and that the assays should never have been offered.

Highlights (2)

confrontationDas corrected the defense's characterization of the Edison validation problem: his criticism concerned how the standards were used, and he concluded the assays should never have been offered or their validation reports signed.Open in transcript →
Quote“SO I WAS NOT SCRUTINIZING THE TAE COLUMN SO TO SPEAK, BUT MORE THE USE OF IT.”— Kingshuk DasDas corrected the defense's framing and distinguished the numerical total-allowable-error standards from how those standards were applied.Open in transcript →
RedirectKingshuk Das — RedirectKingshuk DasRobert S. Leach4highlights88lines spoken

Summary

Das clarified that the next-generation device was not used clinically, described Holmes's control over laboratory resources, and said broader quality-control data supported voiding tests despite disagreement over how to characterize the problems.

Highlights (4)

testimony highlightDas said his review extended beyond the quality-control examples in the CMS report, that those examples were representative of what he found, and that the broader data showed quality-control alarm signals.Open in transcript →
testimony highlightUsing an email about modified ADVIA assays, Das explained that he rejected a proposed multi-analyte threshold and considered analyte-by-analyte review the correct approach; he characterized his Edison decision as following the data.Open in transcript →
Quote“I WAS JUST FOLLOWING THE DATA.”— Kingshuk DasDas rejected the suggestion that voiding Edison tests was merely a conservative choice and framed it as data-driven.Open in transcript →
Quote“THAT CHARACTERIZATION WAS THAT THE PROBLEMS WERE DUE TO ISSUES WITH QUALITY CONTROL AND QUALITY ASSURANCE RATHER THAN THE INSTRUMENT ITSELF.”— Kingshuk DasDas identified the explanation for the test voiding with which he disagreed.Open in transcript →
RecrossKingshuk Das — RecrossKingshuk DasLance A. Wade2highlights53lines spoken

Summary

Das confirmed signing counsel-prepared CMS letters, qualified his agreement with their characterization, and said Holmes lacked clinical-laboratory expertise in several technical areas.

Highlights (2)

testimony highlightDas said quality-control results supported voiding Edison results in part, and he distinguished his disagreement with a particular characterization from his acceptance of the letter as a whole.Open in transcript →
Quote“I BELIEVE I DISAGREED WITH THAT PARTICULAR CHARACTERIZATION, BUT THE LETTER AS A WHOLE WAS ACCEPTABLE.”— Kingshuk DasDas distinguished his technical disagreement with one characterization from his overall acceptance of the CMS letter he signed.Open in transcript →

Day 33

ProceduralLIS Evidence and Trial-Management HearingMentioned

Summary

The court heard competing positions on whether LIS cross-examination had opened the door to broader government evidence and whether the defense could later argue that missing LIS data reflected a failure of proof. The defense declined to limit its arguments, and the court issued no new ruling.

Mentioned in this proceeding.

Day 36

ProceduralMotion to Exclude Fabrizio Bonanni Testimony and Late DisclosuresMentioned

Summary

The government sought to exclude Fabrizio Bonanni's proposed testimony based on relevance and late disclosures. The defense argued that his knowledge of Minilab capabilities and Holmes's later conduct bore on intent. The court raised foundation, hearsay, discovery, and scheduling concerns but issued no exclusion ruling.

Mentioned in this proceeding.

ProceduralRule 29 Motion and Evidentiary Record MattersMentioned

Summary

The defense renewed challenges to the CMS report, Erin Tompkins's HIV-result evidence, and evidence affected by the unavailable LIS database. Holmes also made a Rule 29 motion, which the court took under submission, and the court limited the defense's patent summary to applications filed through 2016 before the defense called Trent Middleton.

Mentioned in this proceeding.

Day 39

DirectElizabeth A. Holmes — DirectElizabeth A. HolmesKevin M. Downey1highlightMentioned

Summary

Holmes described Theranos's military projects, demonstrations, laboratory oversight, and regulatory history before giving emotional testimony alleging coercion and sexual abuse by Ramesh Balwani. She denied that Balwani forced her investor or press statements, addressed the 2015 CMS failures and later remediation, and said she never sold her Theranos shares.

Mentioned in this proceeding.

Highlights (1)

testimony highlightHolmes said she accepted laboratory director Kingshuk Das's recommendation to void certain test results after the CMS findings, despite views from research personnel that laboratory operations rather than the assays had failed.Open in transcript →

Day 42

RedirectElizabeth A. Holmes — RedirectElizabeth A. HolmesKevin M. DowneyMentioned

Summary

Holmes used redirect to explain Theranos's laboratory oversight, modified analyzers, financial projections, partner reports, trade-secret restrictions, and responses to Tyler Shultz. She attributed operational and technical work to others while acknowledging authority over investor presentations and explaining nondisclosure of modified systems as trade-secret protection.

Mentioned in this proceeding.

Day 44

Day 45

Day 46

ClosingClosing Argument by the ProsecutionJeff SchenkMentioned

Summary

The prosecution argued that Holmes knowingly deceived investors and patients, linked the documentary and testimonial record to the conspiracy and wire-fraud elements, rebutted the principal defense themes, and requested guilty verdicts on all remaining counts.

Mentioned in this proceeding.

Day 47