---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-25-091469"
form_type: "8-K"
ticker: "COLB"
cik: "0000887343"
company_name: "COLUMBIA BANKING SYSTEM, INC."
filed_at: "2025-04-23T23:59:59+00:00"
generated_at: "2026-05-23T08:46:18.692442+00:00"
event_type: "m_and_a"
sentiment: "positive"
materiality_score: 0.85
calibrated_materiality_score: 0.85
confidence: "high"
source: SEC EDGAR
---

# Columbia Banking to acquire Pacific Premier Bancorp in $2B all-stock deal

## Summary
- COLB to acquire PPBI at 0.9150x exchange ratio, valuing PPBI at ~$20.83/share; combined assets ~$70B
- Deal expected to deliver mid-teens EPS accretion to COLB; tangible book dilution earned back in ~3 years
- Combined company will have ~$57B deposits; COLB gains top-10 deposit share in Southern California
- Transaction expected to close in H2 2025; subject to regulatory and shareholder approvals
- COLB plans to rename Umpqua Bank to Columbia Bank later this year

## SEC filing metadata
- accession: 0001193125-25-091469
- form_type: 8-K
- ticker: COLB
- cik: 0000887343
- company_name: COLUMBIA BANKING SYSTEM, INC.
- filed_at: 2025-04-23T23:59:59+00:00
- event_type: m_and_a
- sentiment: positive
- materiality_score: 0.85
- calibrated_materiality_score: 0.85
- confidence: high
- sec_items: 7.01, 8.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/887343/000119312525091469/0001193125-25-091469-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/887343/000119312525091469/d908038d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-25-091469
- JSON: https://secwatch.observer/filing/0001193125-25-091469.json
- Plain text: https://secwatch.observer/filing/0001193125-25-091469.txt

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