---
schema_version: "secwatch.filing_event.v1"
accession: "0001193125-25-119311"
form_type: "8-K"
ticker: "NUE"
cik: "0000073309"
company_name: "NUCOR CORP"
filed_at: "2025-05-14T23:59:59+00:00"
generated_at: "2026-05-21T11:29:18.414536+00:00"
event_type: "cyber"
sentiment: "negative"
materiality_score: 0.6
calibrated_materiality_score: 0.6
confidence: "medium"
source: SEC EDGAR
---

# Nucor reports cybersecurity incident; halts some production, now restarting

## Summary
- Unauthorized third-party access to IT systems detected; incident response plan activated.
- Potentially affected systems taken offline; certain production operations temporarily halted.
- Restarting affected operations; investigation ongoing with external experts and federal law enforcement.
- No specifics on data compromise, customer impact, or financial exposure yet; company monitoring materiality.

## SEC filing metadata
- accession: 0001193125-25-119311
- form_type: 8-K
- ticker: NUE
- cik: 0000073309
- company_name: NUCOR CORP
- filed_at: 2025-05-14T23:59:59+00:00
- event_type: cyber
- sentiment: negative
- materiality_score: 0.6
- calibrated_materiality_score: 0.6
- confidence: medium
- sec_items: 1.05
- EDGAR index: https://www.sec.gov/Archives/edgar/data/73309/000119312525119311/0001193125-25-119311-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/73309/000119312525119311/d795264d8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001193125-25-119311
- JSON: https://secwatch.observer/filing/0001193125-25-119311.json
- Plain text: https://secwatch.observer/filing/0001193125-25-119311.txt

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