---
schema_version: "secwatch.filing_event.v1"
accession: "0001140361-23-024280"
form_type: "8-K"
ticker: "KNF"
cik: "0001955520"
company_name: "Knife River Corp"
filed_at: "2023-05-12T23:59:59+00:00"
generated_at: "2026-06-15T02:55:18.225854+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.75
calibrated_materiality_score: 0.75
confidence: "high"
source: SEC EDGAR
---

# Knife River spin-off from MDU Resources set for May 31; 1-for-4 ratio

## Summary
- Registration Statement on Form 10 declared effective May 10; final Information Statement dated May 12.
- One share of KNF common stock distributed for every four shares of MDU common held on May 22 record date.
- Distribution expected at 11:59 p.m. ET on May 31; when-issued trading (KNF WI) begins May 25.
- MDU Resources will distribute approximately 90% of outstanding Knife River shares to its stockholders.

## SEC filing metadata
- accession: 0001140361-23-024280
- form_type: 8-K
- ticker: KNF
- cik: 0001955520
- company_name: Knife River Corp
- filed_at: 2023-05-12T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.75
- calibrated_materiality_score: 0.75
- confidence: high
- sec_items: 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1955520/000114036123024280/0001140361-23-024280-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1955520/000114036123024280/ny20006220x15_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001140361-23-024280
- JSON: https://secwatch.observer/filing/0001140361-23-024280.json
- Plain text: https://secwatch.observer/filing/0001140361-23-024280.txt

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