Archimedes Tech SPAC Partners ATIIW Institutional Ownership

Ownership Summary

Archimedes Tech SPAC Partners II Co. (NASDAQ:ATIIW) has 38 institutional investors that have filed 13F reports for the period ending March 2026.

• These investors held 50.6% of outstanding shares in March 2026, down from 52.1% in December 2025.
• Their total shares held in ATIIW increased 1.3% from the prior quarter, while the number of investors in Archimedes Tech SPAC Partners stayed flat year over year.
• Among the 38 funds, 8 bought more Archimedes Tech SPAC Partners shares, 6 sold down, and 24 held their ground.
• Institutional investors collectively held 10.26Mn shares in Archimedes Tech SPAC Partners as of March 2026, up by 131.39K shares quarter on quarter, and with no net change year over year.
• Harraden Circle Investments, LLC holds the largest position in ATIIW at 1.61Mn shares as of March 31, 2026, or 7.93% of shares outstanding.
• Leading buyers of Archimedes Tech SPAC Partners shares for the quarter ending March 2026 were Toronto Dominion Bank (515.4K), K2 PRINCIPAL FUND, L.P. (239.9K), Lineage Point Capital LP (87.69K), RLH Capital LLC (47.38K), Clear Street Group Inc. (40.38K).
• The biggest sellers of Archimedes Tech SPAC Partners for the quarter ending March 2026 included Alberta Investment Management Corp (375.0K), DLD Asset Management, LP (241.9K), Harraden Circle Investments, LLC (125.0K), CSS LLC/IL (52.81K), GLAZER CAPITAL, LLC (30.15K).
• Per Business Quant, the top 10 investors in ATIIW for the quarter ending March 2026 include Harraden Circle Investments, LLC (1.61Mn), LINDEN ADVISORS LP (860.96K), TENOR CAPITAL MANAGEMENT Co., L.P. (750.0K), Magnetar Financial LLC (650.0K), Toronto Dominion Bank (554.67K), HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND (500.0K), Shaolin Capital Management LLC (500.0K), CSS LLC/IL (487.62K), AQR Arbitrage LLC (479.21K), LMR Partners LLP (425.0K).