SILVERBOX CORP IV - Class A Ordinary Shares, par value $0.0001 per share (SBXDU)

Q: What does CUSIP G81354113 represent in this 13F holders report?

CUSIP G81354113 is the security identifier for SBXDU - SILVERBOX CORP IV - Class A Ordinary Shares, par value $0.0001 per share used to aggregate holder disclosures.

Q: How many institutions held SBXDU - SILVERBOX CORP IV - Class A Ordinary Shares, par value $0.0001 per share in Q1 2026?

3 institutional investors reported SBXDU - SILVERBOX CORP IV - Class A Ordinary Shares, par value $0.0001 per share for Q1 2026. Use the holders table for investor-level position and value details.

CUSIP: G81354113

Q1 2026 13F Holders as of 31 Mar 2026

Security type / class: Equity / Class A Ordinary Shares, par value $0.0001 per share
Total 13F shares: 44,167
Total 13F value: $131,949
Share change: +35,098
SEC-reported price per share: $10.50
Number of holders: 3
Value change: +$35,232
Number of buys: 2
Number of sells: 1
Shares outstanding: 20,467,203

Security key

G81354113

Report period

Q1 2026

Institutions

Top holders

SBXDU full security history Ownership snapshot Full 13F holder table Newer quarter: Q2 2026 Previous quarter: Q4 2025 SilverBox Corp IV SEC filings SilverBox Corp IV company facts

Broader feeds

Latest 13F filings Latest 13D/G filings Investors directory

Reporting periods

Holder history for CUSIP G81354113

Newer quarter: Q2 2026 Previous quarter: Q4 2025

Recent filing periods:

Q2 2026 Q1 2026 Q4 2025 Q3 2025

Ownership snapshot

Top reported holders of SBXDU - SILVERBOX CORP IV - Class A Ordinary Shares, par value $0.0001 per share (13F + 13D/G + 3/4/5)

Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.

Comparable stake leader

SilverBox Sponsor IV LLC

Disclosed value leader

SilverBox Sponsor IV LLC

Comparable rows

15/15

Latest evidence

31 Mar 2026

13D/G 13F Lead comparable stake: 21% 13D/G row: SilverBox Sponsor IV LLC Showing 1-6 of 15 holder rows.

Quick read

SilverBox Sponsor IV LLC leads the comparable SEC ownership view at 21%.

15 of 15 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.

Open SEC evidence Opens SilverBox Sponsor IV LLC's linked filing trail.

Comparable ownership Top 5

SilverBox Sponsor IV LLC 21%

MIZUHO FINANCIAL GROUP INC 8%

BERKLEY W R CORP 7.4%

Polar Asset Management Partners Inc. 7.2%

BARCLAYS PLC 7%

Ownership % is shown only when SEC disclosures are safely comparable across share classes.

Detailed SEC evidence table Showing 1-6 of 15 holder rows

Holder	Evidence	Ownership %	Position	12M Net Δ	As of
SilverBox Sponsor IV LLC	13D/G 13D/G	21%	$56,131,950 5,455,000 shares	$0	31 Dec 2024
MIZUHO FINANCIAL GROUP INC	13D/G 13D/G	8%	$17,411,220 1,645,673 shares	$0	31 Dec 2025
BERKLEY W R CORP	13D/G 13F W. R. Berkley Corporation · Company 13D/G 13F	7.4%	$15,903,016 1,514,573 shares	$0	31 Mar 2026
Polar Asset Management Partners Inc.	13D/G 13F Company 13D/G 13F	7.2%	$16,894,496 1,480,000 shares	$0	30 Jun 2025
BARCLAYS PLC	13D/G 13D/G	7%	$15,320,795 1,431,850 shares	+$4,931,876	31 Mar 2026
GOLDMAN SACHS GROUP INC	13D/G 13F THE GOLDMAN SACHS GROUP, INC. · Company 13D/G 13F	3.2%	$6,847,610 654,022 shares	-$9,976,936	30 Sep 2025

How to read this table

Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.

13F holder rows

Institutional holders as of Q1 2026

Investor-level positions for this CUSIP, loaded as an interactive table.

Institutions

44,167

Rows available

Investor	Option	Weight %	Change %	SEC-reported value	* Price	Shares	Share Change	Activity	Report Period

^* SEC-reported price is the security price as of the portfolio date and can indicate the last known price at which the security was still held. The marker flags a reported price that did not pass the local price check.

Compare Q1 2026 vs Q4 2025 Across Filers

Q4 2025 holders

Q1 2026 holders

Holder diff

Investor	Q4 2025 Shares	Q1 2026 Shares	Share Diff	Share Chg %	Q4 2025 value	Q1 2026 value	Value change	Value Chg %

Trend: ostatnie 8 kwartałów (+ wybrane okresy porównania).

Quarterly Holders Trend

Quarterly Value Trend

Quarterly Shares Trend