---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-23-277887"
form_type: "8-K"
ticker: null
cik: "0001845337"
company_name: "Day One Biopharmaceuticals, Inc."
filed_at: "2023-11-15T23:59:59+00:00"
generated_at: "2026-06-08T02:45:15.192860+00:00"
event_type: "other"
sentiment: "neutral"
materiality_score: 0.3
calibrated_materiality_score: 0.3
confidence: "high"
source: SEC EDGAR
---

# Day One Biopharma dismisses EY as auditor, appoints PwC effective Nov 10, 2023

## Summary
- Audit Committee dismissed EY on Nov 10, 2023; no disagreements or reportable events in prior periods.
- PwC appointed as independent registered public accounting firm for fiscal year ending Dec 31, 2023.
- EY's reports for FY2021 and FY2022 were unqualified and contained no adverse opinions.
- Neither the company nor anyone on its behalf consulted PwC on accounting matters before engagement.

## SEC filing metadata
- accession: 0001193125-23-277887
- form_type: 8-K
- cik: 0001845337
- company_name: Day One Biopharmaceuticals, Inc.
- filed_at: 2023-11-15T23:59:59+00:00
- event_type: other
- sentiment: neutral
- materiality_score: 0.3
- calibrated_materiality_score: 0.3
- confidence: high
- sec_items: 4.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1845337/000119312523277887/0001193125-23-277887-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1845337/000119312523277887/d361807d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-23-277887
- JSON: https://secwatch.observer/filing/0001193125-23-277887.json
- Plain text: https://secwatch.observer/filing/0001193125-23-277887.txt

## Key facts
- Auditor Changes
  Day One Biopharmaceuticals, Inc. engaged PricewaterhouseCoopers LLP as its auditor.
  - Action: engagement
  - Auditor: PricewaterhouseCoopers LLP
  source text: On November 10, 2023, the Audit Committee approved the engagement of PricewaterhouseCoopers LLP ("PwC") as the Company's independent registered public accounting firm for the fiscal year ending December 31, 2023.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1845337/000119312523277887/0001193125-23-277887-index.htm
- Auditor Changes
  Day One Biopharmaceuticals, Inc. dismissed Ernst & Young LLP as its auditor.
  - Action: dismissal
  - Auditor: Ernst & Young LLP
  - Successor: PricewaterhouseCoopers LLP
  source text: dismissed Ernst & Young LLP ("EY") as the Company's independent registered public accounting firm.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1845337/000119312523277887/0001193125-23-277887-index.htm

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