---
schema_version: "secwatch.filing_event.v1"
accession: "0001437749-23-015468"
form_type: "8-K"
ticker: "ATOS"
cik: "0001488039"
company_name: "ATOSSA THERAPEUTICS, INC."
filed_at: "2023-05-22T23:59:59+00:00"
generated_at: "2026-06-14T18:11:39.600530+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.4
calibrated_materiality_score: 0.4
confidence: "high"
source: SEC EDGAR
---

# Atossa Therapeutics dismisses BDO, appoints Ernst & Young as new auditor

## Summary
- On May 17, 2023, Atossa dismissed BDO USA LLP as independent auditor; no accounting disagreements.
- BDO's 2021/2022 audit reports were unqualified; no adverse opinions or scope modifications.
- A 2020 material weakness in internal controls over financial reporting was remediated by end of 2021.
- EY appointed as new auditor for fiscal year ending December 31, 2023.
- No prior consultations with EY on accounting principles or disagreements.

## SEC filing metadata
- accession: 0001437749-23-015468
- form_type: 8-K
- ticker: ATOS
- cik: 0001488039
- company_name: ATOSSA THERAPEUTICS, INC.
- filed_at: 2023-05-22T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.4
- calibrated_materiality_score: 0.4
- confidence: high
- sec_items: 4.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1488039/000143774923015468/0001437749-23-015468-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1488039/000143774923015468/atos20230515_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001437749-23-015468
- JSON: https://secwatch.observer/filing/0001437749-23-015468.json
- Plain text: https://secwatch.observer/filing/0001437749-23-015468.txt

## Key facts
- Auditor Changes
  ATOSSA THERAPEUTICS, INC. dismissed BDO USA LLP as its auditor.
  - Action: dismissal
  - Auditor: BDO USA LLP
  - Successor: Ernst & Young LLP
  source text: On May 17, 2023 (the “ Effective Date ”), the Audit Committee dismissed BDO USA LLP (“ BDO ”) as the Company’s independent registered public accounting firm, effective as of that date.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1488039/000143774923015468/0001437749-23-015468-index.htm
- Auditor Changes
  ATOSSA THERAPEUTICS, INC. engaged Ernst & Young LLP as its auditor.
  - Action: engagement
  - Auditor: Ernst & Young LLP
  source text: The Audit Committee, on and effective as of the Effective Date, appointed Ernst & Young LLP (“EY”) 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/1488039/000143774923015468/0001437749-23-015468-index.htm

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