---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-25-137853"
form_type: "8-K"
ticker: "LYEL"
cik: "0001806952"
company_name: "Lyell Immunopharma, Inc."
filed_at: "2025-06-09T23:59:59+00:00"
generated_at: "2026-05-19T17:25:48.054399+00:00"
event_type: "leadership"
sentiment: "neutral"
materiality_score: 0.25
calibrated_materiality_score: 0.25
confidence: "high"
source: SEC EDGAR
---

# Lyell Immunopharma appoints Mark Bachleda to Board, expanding size to 8

## Summary
- Board increased from 7 to 8 directors; Mark Bachleda, Pharm.D., M.B.A., appointed as Class I director effective June 9, 2025.
- Term expires at 2028 annual meeting; compensation per non-employee director policy adjusted for 1-for-20 reverse stock split.
- Standard indemnification agreement entered with Dr. Bachleda.

## SEC filing metadata
- accession: 0001193125-25-137853
- form_type: 8-K
- ticker: LYEL
- cik: 0001806952
- company_name: Lyell Immunopharma, Inc.
- filed_at: 2025-06-09T23:59:59+00:00
- event_type: leadership
- sentiment: neutral
- materiality_score: 0.25
- calibrated_materiality_score: 0.25
- confidence: high
- sec_items: 5.02
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1806952/000119312525137853/0001193125-25-137853-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1806952/000119312525137853/d940968d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-25-137853
- JSON: https://secwatch.observer/filing/0001193125-25-137853.json
- Plain text: https://secwatch.observer/filing/0001193125-25-137853.txt

## Key facts
- Executive change
  Mark Bachleda was appointed as Director at Lyell Immunopharma, Inc..
  - Action: appointed
  - Role: Director
  source text: on June 9, 2025, the Board of Directors (the “Board”) of Lyell Immunopharma, Inc. (the “Company”) increased the authorized size of the Board from seven directors to eight directors and, upon recommendation of the Nominating and Corporate Governance Committee of the Board, appointed Mark Bachleda, Pharm.D., M.B.A., to the Board as a Class I director.
  evidence_url: https://www.sec.gov/Archives/edgar/data/1806952/000119312525137853/0001193125-25-137853-index.htm

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