---
schema_version: "secwatch.filing_event.v1"
accession: "0001104659-21-100444"
form_type: "8-K"
ticker: "BDTX"
cik: "0001701541"
company_name: "Black Diamond Therapeutics, Inc."
filed_at: "2021-08-05T23:59:59+00:00"
generated_at: "2026-06-29T21:48:49.719110+00:00"
event_type: "leadership"
sentiment: "neutral"
materiality_score: 0.65
calibrated_materiality_score: 0.65
confidence: "high"
source: SEC EDGAR
---

# Black Diamond appoints interim CMO and new CSO; CMO and CSO depart

## Summary
- Karsten Witt appointed Interim CMO, effective Aug 4, 2021, succeeding Rachel Humphrey.
- Rachel Humphrey offered separation agreement with severance, advisory role until Feb 28, 2022; vested option extension.
- Elizabeth Buck appointed Chief Scientific Officer, effective Aug 11, 2021, succeeding Christopher Roberts.
- Christopher Roberts resigned to become CEO at another company; will serve as advisor post-departure.

## SEC filing metadata
- accession: 0001104659-21-100444
- form_type: 8-K
- ticker: BDTX
- cik: 0001701541
- company_name: Black Diamond Therapeutics, Inc.
- filed_at: 2021-08-05T23:59:59+00:00
- event_type: leadership
- sentiment: neutral
- materiality_score: 0.65
- calibrated_materiality_score: 0.65
- confidence: high
- sec_items: 5.02
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1701541/000110465921100444/0001104659-21-100444-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1701541/000110465921100444/tm2123993d1_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001104659-21-100444
- JSON: https://secwatch.observer/filing/0001104659-21-100444.json
- Plain text: https://secwatch.observer/filing/0001104659-21-100444.txt

## Key facts
- Executive change
  Elizabeth Buck was appointed as Chief Scientific Officer at Black Diamond Therapeutics, Inc..
  - Action: appointed
  - Role: Chief Scientific Officer
  source text: Effective August 11 , 2021, Dr. Buck succeeds Christopher Roberts, Ph.D., Chief Scientific Officer, who notified the Company on July 12, 2021 of his resignation from the Company to assume the role of chief executive officer at another company.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1701541/000110465921100444/0001104659-21-100444-index.htm
- Executive change
  Karsten Witt was appointed as Interim Chief Medical Officer at Black Diamond Therapeutics, Inc..
  - Action: appointed
  - Role: Interim Chief Medical Officer
  source text: Dr. Witt succeeds Rachel Humphrey, M.D., Chief Medical Officer, effective August 4, 2021.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1701541/000110465921100444/0001104659-21-100444-index.htm
- Executive change
  Rachel Humphrey departed as Chief Medical Officer at Black Diamond Therapeutics, Inc..
  - Action: succeeded
  - Role: Chief Medical Officer
  source text: Dr. Witt succeeds Rachel Humphrey, M.D., Chief Medical Officer, effective August 4, 2021.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1701541/000110465921100444/0001104659-21-100444-index.htm
- Executive change
  Christopher Roberts resigned as Chief Scientific Officer at Black Diamond Therapeutics, Inc..
  - Action: resigned
  - Role: Chief Scientific Officer
  source text: Dr. Buck succeeds Christopher Roberts, Ph.D., Chief Scientific Officer, who notified the Company on July 12, 2021 of his resignation from the Company to assume the role of chief executive officer at another company.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1701541/000110465921100444/0001104659-21-100444-index.htm

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.