Who owns Archimedes Tech SPAC Partners II Co.?
Prices and market caps: Cboe delayed data, at least 15 minutes delayed. Not real-time. Fundamentals from company filings.
Institutional ownership of ARCIU from SEC Form 13F filings across 15 reporting managers. All positions are from one synchronized reporting period — 2026-06-30 books, filed up to 45 days after quarter end — so every row is comparable.
As of the 2026-06-30 reporting period, 15 institutions disclosed 4.6M shares of Archimedes Tech SPAC Partners II Co. worth $47.3M — about 15.6% of shares outstanding; the largest disclosed holder is LMR Partners LLP. Source: SEC Form 13F filings, parsed by EvidInvest.
15
13F holders
$47.3M
value, 2026 filers
15.6%
of shares outstanding (4.6M sh)
1
new positions (2026 filers)
Top institutional holders
ordered by shares owned · positions as of 2026-06-30 · % of fund = share of the manager's own book · % of co. = share of ARCIU's shares outstanding
| # | Manager | Shares | Value | % of fund | % of co. | Δ shares QoQ |
|---|---|---|---|---|---|---|
| 1 | LMR Partners LLP | 1.3M | $12.7M | 0.0% | 4.2% | 0.0% |
| 2 | TUDOR INVESTMENT CORP ET AL | 650,000 | $6.6M | 0.0% | 2.2% | 0.0% |
| 3 | TORONTO DOMINION BANK | 646,217 | $6.6M | 0.0% | 2.2% | +158.5% |
| 4 | OMERS ADMINISTRATION Corp | 480,000 | $4.9M | 0.0% | 1.6% | 0.0% |
| 5 | ARISTEIA CAPITAL, L.L.C. | 400,779 | $4.1M | 0.1% | 1.4% | +0.2% |
| 6 | Lineage Point Capital LP | 288,776 | $3.0M | 0.6% | 1% | +5.0% |
| 7 | BlueCrest Capital Management Ltd | 275,000 | $2.8M | 0.1% | 0.9% | 0.0% |
| 8 | MILLENNIUM MANAGEMENT LLC | 179,743 | $1.8M | 0.0% | 0.6% | -48.6% |
| 9 | Qube Research & Technologies Ltd | 150,000 | $1.5M | 0.0% | 0.5% | 0.0% |
| 10 | Calamos Advisors LLC | 124,000 | $1.3M | 0.0% | 0.4% | 0.0% |
| 11 | Westchester Capital Management, LLC | 100,000 | $1.0M | 0.0% | 0.3% | 0.0% |
| 12 | Clear Street Group Inc. | 34,256 | $349,069 | 0.0% | 0.1% | +240.4% |
| 13 | HRT FINANCIAL LP | 25,000 | $256,000 | 0.0% | 0.1% | 0.0% |
| 14 | Tuttle Capital Management, LLC | 10,769 | $109,413 | 0.1% | 0% | +7.7% |
| 15 | GLAZER CAPITAL, LLCNEW | 10,523 | $110,000 | 0.0% | 0% | new |
Source: SEC Form 13F-HR filings (institutional managers over $100M in US-listed positions). 13Fs disclose long positions only, up to 45 days after quarter end; each manager's latest filed quarter is shown per row and dollar values are the manager's filed marks. Aggregates labeled "2026 filers" count only managers whose latest book is a 2026 quarter. Related: valuation. Research, not investment advice.