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ATII · Archimedes Tech SPAC Partners II Co. · Shareholders & Ownership

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$8.20 +1.03 (+14.37%)
Market Cap
$221.04M
Shares
29.59M
Volume · Oct 21 49.54K Avg daily vol (3M) 258.12K

Every disclosed holder of ATII in one list: 13F institutions, Schedule 13D and 13G filers, insiders (Forms 3, 4 and 5) and registered funds, each from its own latest filing. Holders nest by CIK and SEC reporting links, never by name, and each is summed once.

Who Owns ATII

13F quarter Jun 30, 2026

No chart: the summed disclosures exceed shares outstanding, so they are not parts of one whole.

Holder group Shares % Out
Institutional (13F) 26,084,208 88.15%
Insiders (Forms 3, 4, 5) 18,310,000 61.88%
13D/G-only blocks 1,148,590 3.88%
Remaining 15,952,798 -53.91%
Registered funds (N-PORT, not summed) 820 0.00%

Shares outstanding: 29,590,000, the issuer's latest cover-page count restated onto today's split basis.

Remaining is negative: the summed disclosures exceed shares outstanding, as when filings are dated at different times or holders that do not disclose their links count the same shares. It is flagged, not clipped.

13D/G-only counts each filer's latest 13D or 13G that no 13F report of the listing contains, that names no 13F filer and that no counted insider files. Funds are never summed: their shares sit inside their advisers' 13F reports.

Holders of ATII

# Holder Shares
1
Archimedes Tech SPAC Sponsors II LLC
Insider CIK 2055303 · Feb 12, 2025
10% Owner, issuer-wide
6,280,000
2
Long Long
Insider CIK 1793151 · Feb 12, 2025
Chief Financial Officer, issuer-wide
6,280,000
3
Archimedes Tech SPAC Partners II Co.
Insider CIK 2028516 · Feb 10, 2025
10% Owner, issuer-wide
5,750,000
4
TENOR CAPITAL MANAGEMENT Co., L.P.
13F CIK 1346554 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
2,117,830
5
Magnetar Financial LLC
13F CIK 1352851 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
1,734,902
6
D. E. Shaw & Co., Inc.
13F CIK 1009207 · Unknown · Jun 30, 2026
Classes ATII, ATIIW
1,426,000
7
Fort Baker Capital Management LP
13F CIK 1688382 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
1,371,923
8
Harraden Circle Investments, LLC
13F CIK 1910592 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
1,366,261
9
Linden Advisors LP
13F CIK 1279396 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
1,352,411
10
Decagon Asset Management LLP
13F CIK 1950677 · Unknown · Jun 30, 2026
Classes ATII, ATIIW
1,269,131
11
BARCLAYS PLC
13G CIK 312069 · Bank · Dec 31, 2025
Rule 13d-1(b), qualified institution
1,148,590
12
LMR Partners LLP
13F CIK 1578621 · Exempt reporting adviser · Jun 30, 2026
Classes ATII, ATIIW
1,092,679
13
AQR Arbitrage LLC
13F CIK 1167456 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
1,071,628
14
ARISTEIA CAPITAL, L.L.C.
13F CIK 1080171 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
988,491
15
K2 PRINCIPAL FUND, L.P.
13F CIK 1461790 · Unknown · Jun 30, 2026
Classes ATII, ATIIW
806,945
16
Ghisallo Capital Management LLC
13F CIK 1825214 · Registered investment adviser · Jun 30, 2026
800,000
17
Alberta Investment Management Corp
13F CIK 1463559 · Non-US institution · Jun 30, 2026
Classes ATII, ATIIW
775,000
18
Hudson Bay Capital Management LP
13F CIK 1393825 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
739,994
19
TWO SIGMA INVESTMENTS, LP
13F CIK 1179392 · Registered investment adviser · Jun 30, 2026
725,000
20
Sculptor Capital LP
13F CIK 1054587 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
702,819
21
MOORE CAPITAL MANAGEMENT, LP
13F CIK 1448574 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
675,000
22
Shay Capital LLC
13F CIK 1723643 · Unknown · Jun 30, 2026
623,687
23
Governors Lane LP
13F CIK 1644187 · Registered investment adviser · Jun 30, 2026
604,857
24
HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND
13F CIK 1535845 · Non-US institution · Jun 30, 2026
500,000
25
Radcliffe Capital Management, L.P.
13F CIK 1218275 · Registered investment adviser · Jun 30, 2026
478,061
26
Mint Tower Capital Management B.V.
13F CIK 1666606 · Unknown · Jun 30, 2026
Classes ATII, ATIIW
430,000
27
WHITEBOX ADVISORS LLC
13F CIK 1257391 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
375,000
28
FNY Investment Advisers, LLC
13F CIK 1742998 · Unknown · Jun 30, 2026
327,200
29
DLD Asset Management, LP
13F CIK 1578299 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
264,853
30
Shaolin Capital Management LLC
13F CIK 1766806 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
257,811
31
CITADEL ADVISORS LLC
13F CIK 1423053 · Registered investment adviser · Jun 30, 2026
250,266
32
RIVERNORTH CAPITAL MANAGEMENT, LLC
13F CIK 1447578 · Registered investment adviser · Jun 30, 2026
224,942
33
Periscope Capital Inc.
13F CIK 1695320 · Exempt reporting adviser · Jun 30, 2026
Classes ATII, ATIIW
215,000
34
GOLDMAN SACHS GROUP INC
13F CIK 886982 · Holding company · Jun 30, 2026
205,090
35
L1 Global Manager Pty Ltd
13F CIK 1878742 · Unknown · Jun 30, 2026
200,000
36
MMCAP International Inc. SPC
13F CIK 1304857 · Unknown · Jun 30, 2026
Classes ATII, ATIIW
187,500
37
BNP PARIBAS ARBITRAGE, SA
13F CIK 1166588 · Non-US institution · Jun 30, 2026
Classes ATII, ATIIW
185,717
38
Jain Global LLC
13F CIK 2024579 · Registered investment adviser · Jun 30, 2026
185,108
39
SkyView Investment Advisors, LLC
13F CIK 1848237 · Unknown · Jun 30, 2026
182,495
40
CSS LLC/IL
13F CIK 1103646 · Unknown · Jun 30, 2026
151,718
41
Verition Fund Management LLC
13F CIK 1454027 · Registered investment adviser · Jun 30, 2026
140,797
42
TUDOR INVESTMENT CORP ET AL
13F CIK 923093 · Registered investment adviser · Jun 30, 2026
123,842
43
Clear Street Group Inc.
13F CIK 1881567 · Unknown · Jun 30, 2026
Classes ATII, ATIIU, ATIIW
99,164
44
CANTOR FITZGERALD, L. P.
13F CIK 1024896 · Unknown · Jun 30, 2026
88,283
45
TORONTO DOMINION BANK
13F CIK 947263 · Bank · Jun 30, 2026
82,550
46
Schonfeld Strategic Advisors LLC
13F CIK 1665241 · Registered investment adviser · Jun 30, 2026
Classes ATII, ATIIW
80,000
47
Baird Financial Group, Inc.
13F CIK 1648711 · Unknown · Jun 30, 2026
78,500
48
Alpine Global Management, LLC
13F CIK 1581655 · Unknown · Jun 30, 2026
71,039
49
MILLENNIUM MANAGEMENT LLC
13F CIK 1273087 · Registered investment adviser · Jun 30, 2026
69,384
50
GLAZER CAPITAL, LLC
13F CIK 1076809 · Registered investment adviser · Jun 30, 2026
50,100

Shares are restated onto today's split basis. Change compares each row with the same holder's previous filing in the same source; a dash means there is none to compare. Nested 13D/G, insider and fund rows are not summed, since a 13F report already holds them.

Showing 1–50 of 66 holders

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Key facts CIK 2028516 CUSIP G04537109 Visit website Investor relations