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ATII · Archimedes Tech SPAC Partners II Co.

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$10.66 +0.01 (+0.09%) At close · Sep 2
Market Cap
$315.43M
Shares
29.59M

Institutional ownership from SEC Form 13F filings. Investment managers with more than $100 million in U.S. equities must disclose their positions every quarter, within 45 days of quarter-end, so the holdings shown can lag the market by up to a quarter.

Holders: 60
Total Value: $189,157,740
Total Shares: 26,071,175

Institutional Ownership Trend

6 quarters

Holder Concentration

Across 60 13F filers · Δ vs Mar 31, 2026
Top Holder
7.8%
Mar 2025 → Jun 2026 · range 6.7% – 7.8%
+1.0 pts
Top 5
34.6%
Mar 2025 → Jun 2026 · range 26.3% – 34.6%
+8.2 pts
Top 10
55.7%
Mar 2025 → Jun 2026 · range 44.7% – 55.7%
+10.9 pts
HHI
425
Mar 2025 → Jun 2026 · range 320 – 425
Broadly held+105

Quarterly Activity

vs Mar 31, 2026
New
12
Increased
6
Decreased
30
Sold Out
12
Unchanged
12
Holder count: 0
Institutional value: -18.1%
Shares held: -20.5%

Top Buyers

vs Mar 31, 2026
Institution Added Now Holds Open

Top Sellers

vs Mar 31, 2026
Institution Sold Now Holds Open

Top New Positions

vs Mar 31, 2026
Institution Acquired Value (USD) Open

Top Sold-Out Positions

vs Mar 31, 2026
Institution Previously Held Last Value (USD) Open
Showing 88 of 88
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Holder Value (USD) % of 13F Shares Open
Key facts CIK 2028516 CUSIP G04537109 13F (30d) 58 filings 57 filers Visit website