Vault-13

QUARTZSEA ACQUISITION CORP QSEA

ORD SHS · Common Stock · CUSIP G7314B104

21 institutional holders -5 vs Q1 2026
7,417,7747.4m shares reported held*
73.2% of all shares outstanding*
$77.8mreported value*
2 new 9 added 8 reduced 7 sold out net sold ≈ $1.2m (-111.7k shares)

* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once. Holder counts are more reliable. Shares outstanding: 10.1m as of 2026-07-13, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $10.49.

Trends to Q2 2026

Institutional holders

Managers reporting a position, each quarter

0102030Q2 25: 25Q3 25: 25Q4 25: 25Q1 26: 26Q2 26: 2121Q2 25Q3 25Q4 25Q1 26Q2 26
Numbers
QuarterHolders
Q2 202525
Q3 202525
Q4 202525
Q1 202626
Q2 202621

Buyers vs sellers

Managers adding to or starting a position, vs cutting or selling out

Bought or addedCut or sold out
20020Q3 25: 7 bought or addedQ3 25: 7 cut or sold outQ3 25Q4 25: 6 bought or addedQ4 25: 4 cut or sold outQ4 25Q1 26: 6 bought or addedQ1 26: 8 cut or sold outQ1 26Q2 26: 11 bought or addedQ2 26: 15 cut or sold outQ2 26
Numbers
QuarterBought or addedCut or sold out
Q3 202577
Q4 202564
Q1 202668
Q2 20261115

Biggest buyers

MIZUHO SECURITIES USA LLC Added +993,296+993.3k
BERKLEY W R CORP Added +688,641+688.6k
Westchester Capital Management, LLC Added +245,000+245.0k
RLH Capital LLC Added +211,100+211.1k
Clear Street Group Inc. New +128,529+128.5k
Polar Asset Management Partners Inc. Added +25,000+25.0k
CITADEL ADVISORS LLC New +10,948+10.9k
AQR Arbitrage LLC Added +1,925+1.9k
D. E. Shaw & Co., Inc. Added +1,500+1.5k
Warberg Asset Management LLC Added +965+965

Biggest sellers

Karpus Management, Inc. Reduced -1,282,040-1.3m
MANGROVE PARTNERS IM, LLC Sold out -408,154-408.2k
Linden Advisors LP Sold out -175,000-175.0k
Crossingbridge Advisors, LLC Sold out -140,189-140.2k
WOLVERINE ASSET MANAGEMENT LLC Reduced -104,034-104.0k
Shaolin Capital Management LLC Reduced -61,746-61.7k
TWO SIGMA INVESTMENTS, LP Sold out -59,288-59.3k
Logan Stone Capital, LLC Sold out -51,553-51.6k
TORONTO DOMINION BANK Reduced -50,000-50.0k
Radcliffe Capital Management, L.P. Sold out -26,553-26.6k

Major shareholders (over 5%)

Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.

HolderStakeChangeShares Last filed
Blue Jay Investment LLC 13D · may seek influence new · filed 2025-04-03
Stated purposeIn connection with the organization of the Issuer, on November 5, 2024, pursuant to a Subscription Agreement, the Issuer issued an aggregate of 1,725,000 ordinary shares as Founder Shares, to the Sponsor for an aggregate purchase price of $25,000. On February 12, 2025, the Issuer and the Sponsor entered into the First Amendment to the Subscription Agreement, pursuant to which the purchased amount of shares was adjusted to 2,415,000 ordinary shares, $0.0104 per ordinary share. On March 17, 2025, the Issuer and the Sponsor entered into the Second Amendment to the Subscription Agreement, pursuant to which the purchased amount of shares was adjusted to 2,898,000 ordinary shares, of which 378,000 are subject to forfeiture if the underwriters' over-allotment option is not exercised in full. Si… Full filing
27.4% new 3.1m≈ $32.2m 2025-04-03
Karpus Management, Inc. 13G · institution +1.1 pts · filed 2026-08-14 9.6% +1.1 pts 974.8k≈ $10.3m 2026-08-14
BERKLEY W R CORP 13G · institution new · filed 2026-08-06 8.9% new 900.0k≈ $9.5m 2026-08-06
MIZUHO FINANCIAL GROUP INC 13G · institution filed 2026-08-13 8.0% 993.3k≈ $9.4m 2026-08-13
Feis Equities LLC 13G · passive investor +1.0 pts · filed 2026-06-08 5.3% +1.0 pts 600.1k≈ $6.2m 2026-06-08

Fell to 5% or below in the last year: WOLVERINE ASSET MANAGEMENT LLC (4.9%, 2026-07-16)

Insider purchases and sales since 1 Apr 2026

Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.

None reported since 1 Apr 2026.

Holders, Q2 2026

#ManagerLocationShares Value% of their portfolioChangeShares change
1 MIZUHO SECURITIES USA LLC 0.17% of their portfolio NEW YORK, NY 1,671,0501.7m $17.3m $17.3m 0.17% Added +993.3k +993,296
2 BERKLEY W R CORP 0.56% of their portfolio Greenwich, CT 1,094,1901.1m $11.5m $11.5m 0.56% Added +688.6k +688,641
3 Karpus Management, Inc. 0.29% of their portfolio Pittsford, NY 974,765974.8k $10.3m $10.3m 0.29% Reduced -1.3m -1,282,040
4 Westchester Capital Management, LLC 0.32% of their portfolio VALHALLA, NY 611,605611.6k $6.4m $6.4m 0.32% Added +245.0k +245,000
5 RIVERNORTH CAPITAL MANAGEMENT, LLC 0.25% of their portfolio WEST PALM BEACH, FL 499,664499.7k $5.3m $5.3m 0.25% Reduced -92 -92
6 WOLVERINE ASSET MANAGEMENT LLC 0.07% of their portfolio CHICAGO, IL 495,488495.5k $5.2m $5.2m 0.07% Reduced -104.0k -104,034
7 Polar Asset Management Partners Inc. 0.07% of their portfolio TORONTO, A6 375,000375.0k $3.9m $3.9m 0.07% Added +25.0k +25,000
8 AQR Arbitrage LLC 0.05% of their portfolio Greenwich, CT 356,213356.2k $3.7m $3.7m 0.05% Added +1.9k +1,925
9 RLH Capital LLC 1.27% of their portfolio Great Neck, NY 252,439252.4k $2.7m $2.7m 1.27% Added +211.1k +211,100
10 Hudson Bay Capital Management LP 0.01% of their portfolio STAMFORD, CT 175,159175.2k $1.8m $1.8m 0.01% Added +159 +159
11 D. E. Shaw & Co., Inc. 0.00% of their portfolio New York, NY 171,612171.6k $1.8m $1.8m 0.00% Added +1.5k +1,500
12 TORONTO DOMINION BANK 0.00% of their portfolio TORONTO, ONTARIO, A6 150,000150.0k $1.6m $1.6m 0.00% Reduced -50.0k -50,000
13 Clear Street Group Inc. 0.00% of their portfolio NEW YORK, NY 128,529128.5k $1.4m $1.4m 0.00% New
14 GLAZER CAPITAL, LLC 0.03% of their portfolio New York, NY 126,887126.9k $1.3m $1.3m 0.03% Reduced -22.7k -22,657
15 GOLDMAN SACHS GROUP INC 0.00% of their portfolio NEW YORK, NY 119,661119.7k $1.3m $1.3m 0.00% Unchanged
16 Shaolin Capital Management LLC 0.07% of their portfolio Miami, FL 114,840114.8k $1.2m $1.2m 0.07% Reduced -61.7k -61,746
17 Dakota Wealth Management 0.01% of their portfolio PALM BEACH GARDENS, FL 49,76049.8k $523.5k $523.5k 0.01% Reduced -19.7k -19,740
18 Warberg Asset Management LLC 0.07% of their portfolio WINNETKA, IL 22,91622.9k $241.1k $241.1k 0.07% Added +965 +965
19 BNP PARIBAS FINANCIAL MARKETS 0.00% of their portfolio PARIS, I0 16,98717.0k $178.7k $178.7k 0.00% Unchanged
20 CITADEL ADVISORS LLC 0.00% of their portfolio MIAMI, FL 10,94810.9k $115.2k $115.2k 0.00% New
21 MORGAN STANLEY 0.00% of their portfolio NEW YORK, NY 6161 $642 $642 0.00% Reduced -10 -10