ARCIU · Archimedes Tech SPAC Partners III Co. · Shareholders & Ownership
Every disclosed holder of ARCIU 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 ARCIU
13F quarter Jun 30, 2026; this listing alone: insiders and shares outstanding are issuer-wide, so they are left outNo chart: shares outstanding cannot be set against these holders.
| Holder group | Shares | % Out |
|---|---|---|
| Institutional (13F) | 4,625,063 | — |
| Insiders (Forms 3, 4, 5) | 0 | — |
| 13D/G-only blocks | 0 | — |
| Registered funds (N-PORT, not summed) | 30,769 | — |
% Out is unavailable: shares outstanding is an issuer-wide count, not one listing's.
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 ARCIU
| # | Holder | Shares | As of | Notes |
|---|---|---|---|---|
| 1 |
LMR Partners LLP
13F
CIK 1578621 · Exempt reporting adviser · Jun 30, 2026
|
1,250,000 | ||
| 2 |
TUDOR INVESTMENT CORP ET AL
13F
CIK 923093 · Registered investment adviser · Jun 30, 2026
|
650,000 | ||
| 3 |
TORONTO DOMINION BANK
13F
CIK 947263 · Bank · Jun 30, 2026
|
646,217 | ||
| 4 |
OMERS ADMINISTRATION Corp
13F
CIK 1053321 · Pension or benefit plan · Jun 30, 2026
|
480,000 | ||
| 5 |
ARISTEIA CAPITAL, L.L.C.
13F
CIK 1080171 · Registered investment adviser · Jun 30, 2026
|
400,779 | ||
| 6 |
Lineage Point Capital LP
13F
CIK 2093311 · Unknown · Jun 30, 2026
|
288,776 | ||
| 7 |
BlueCrest Capital Management Ltd
13F
CIK 1610880 · Unknown · Jun 30, 2026
|
275,000 | ||
| 8 |
MILLENNIUM MANAGEMENT LLC
13F
CIK 1273087 · Registered investment adviser · Jun 30, 2026
|
179,743 | ||
| 9 |
Qube Research & Technologies Ltd
13F
CIK 1729829 · Exempt reporting adviser · Jun 30, 2026
|
150,000 | ||
| 10 |
Calamos Advisors LLC
13F
CIK 1316507 · Registered investment adviser · Jun 30, 2026
|
124,000 | ||
| 11 |
Westchester Capital Management, LLC
13F
CIK 1512805 · Registered investment adviser · Jun 30, 2026
|
100,000 | ||
| 12 |
Clear Street Group Inc.
13F
CIK 1881567 · Unknown · Jun 30, 2026
|
34,256 | ||
| 13 |
HRT FINANCIAL LP
13F
CIK 1475597 · Unknown · Jun 30, 2026
|
25,000 | ||
| 14 |
High Income Securities Fund
Fund
· Registered fund · May 31, 2026
High Income, not summed
|
20,000 | ||
| 15 |
The SPAC and New Issue ETF
Fund
S000070261 · Registered fund · Jun 30, 2026
Collaborative Investment Series Trust, not summed
|
10,769 | ||
| 16 |
Tuttle Capital Management, LLC
13F
CIK 1581641 · Registered investment adviser · Jun 30, 2026
|
10,769 | ||
| 17 |
GLAZER CAPITAL, LLC
13F
CIK 1076809 · Registered investment adviser · Jun 30, 2026
|
10,523 |
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.