---
schema_version: "secwatch.filing_event.v1"
accession: "0001104659-25-107351"
form_type: "8-K"
ticker: "SBXD"
cik: "0002015947"
company_name: "SilverBox Corp IV"
filed_at: "2025-11-06T23:59:59+00:00"
generated_at: "2026-05-17T00:03:11.384330+00:00"
event_type: "other_material"
sentiment: "neutral"
materiality_score: 0.6
calibrated_materiality_score: 0.6
confidence: "high"
source: SEC EDGAR
---

# SilverBox Corp IV amends Preferred Equity Subscription Agreements to allow Bitcoin collateralization

## Summary
- Amendment removes prohibition on pledging Bitcoin purchased with $31M preferred equity proceeds.
- Permits Company to use Bitcoin as collateral or credit support for lending or other financing arrangements.
- Original agreements: 3,100,000 preferred units at $10/unit for aggregate $31,000,000, entered Aug 6, 2025.
- Amendment date: October 31, 2025; parties: Pubco, Company, and Preferred Equity Investors.
- Business combination with Parataxis Holdings still pending; this is a related financing term change.

## SEC filing metadata
- accession: 0001104659-25-107351
- form_type: 8-K
- ticker: SBXD
- cik: 0002015947
- company_name: SilverBox Corp IV
- filed_at: 2025-11-06T23:59:59+00:00
- event_type: other_material
- sentiment: neutral
- materiality_score: 0.6
- calibrated_materiality_score: 0.6
- confidence: high
- sec_items: 1.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/2015947/000110465925107351/0001104659-25-107351-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/2015947/000110465925107351/tm2524487d10_8k.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001104659-25-107351
- JSON: https://secwatch.observer/filing/0001104659-25-107351.json
- Plain text: https://secwatch.observer/filing/0001104659-25-107351.txt

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