Skip to main content
Livermore
Livermore
ZHEN

Archimedes Tech SPAC Partners II Co.

ATII
Exchange
Nasdaq
Industry
Blank Checks
SEC CIK
0002028516

No open-market purchases or sales by Archimedes Tech SPAC Partners II Co. insiders were filed in the last 90 days; 50 institutions reported holding it in 13F filings for Q2 2026, worth $189.6M in total; no superinvestor holds it.

Other share classesATIIUATIIW

13F holders, Q1 2026

Institutional positions in Archimedes Tech SPAC Partners II Co. as of Mar 31, 2026. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works

Institutional holders
54
+6 vs. Q4 2025
Shares held
22.2M
+140.9K (+0.6%) vs. Q4 2025
Total value
$231.3M
+$2.92M (+1.3%) vs. Q4 2025
New holders
9
6 more added
Sold out
3
10 more reduced

1 institution that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.

Compare with Q4 2025: new holders, sold out and not filed yet

Holders and value by quarter

Institutions reporting ATII on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.

Institutional holdersQ1 2026: 54 institutions
Q1 2021: 0 institutionsQ2 2021: 0 institutionsQ3 2021: 0 institutionsQ4 2021: 0 institutionsQ1 2022: 0 institutionsQ2 2022: 0 institutionsQ3 2022: 0 institutionsQ4 2022: 0 institutionsQ1 2023: 0 institutionsQ2 2023: 0 institutionsQ3 2023: 0 institutionsQ4 2023: 0 institutionsQ1 2024: 0 institutionsQ2 2024: 0 institutionsQ3 2024: 0 institutionsQ4 2024: 0 institutionsQ1 2025: 0 institutionsQ2 2025: 42 institutionsQ3 2025: 46 institutionsQ4 2025: 49 institutionsQ1 2026: 54 institutionsQ2 2026: 50 institutions
Value heldQ1 2026: $231.3M
Q1 2021: $0Q2 2021: $0Q3 2021: $0Q4 2021: $0Q1 2022: $0Q2 2022: $0Q3 2022: $0Q4 2022: $0Q1 2023: $0Q2 2023: $0Q3 2023: $0Q4 2023: $0Q1 2024: $0Q2 2024: $0Q3 2024: $0Q4 2024: $0Q1 2025: $0Q2 2025: $216.0MQ3 2025: $225.0MQ4 2025: $230.4MQ1 2026: $231.3MQ2 2026: $189.6M
Institutions holding ATII and their total value by quarter
QuarterHoldersValue
Q2 202650$189.6M
Q1 202654$231.3M
Q4 202549$230.4M
Q3 202546$225.0M
Q2 202542$216.0M
Q1 20250$0
Q4 20240$0
Q3 20240$0
Q2 20240$0
Q1 20240$0
Q4 20230$0
Q3 20230$0
Q2 20230$0
Q1 20230$0
Q4 20220$0
Q3 20220$0
Q2 20220$0
Q1 20220$0
Q4 20210$0
Q3 20210$0
Q2 20210$0
Q1 20210$0

Institutions, Q1 2026

Shares, value and share of portfolio for each institution holding Archimedes Tech SPAC Partners II Co.; share changes are against Q4 2025.

Institutions holding ATII in Q1 2026
InstitutionSharesValue% of portfolioChange in sharesAction
Morgan Stanley62$6450.00%−68−52.3%Reduced
Citadel Advisors LLC10,377$108.4K0.00%+10,377New
Geode Capital Management, LLC11,102$115.6K0.00%+11,102New
Mizuho Securities USA LLC19,469$202.5K0.00%−284,358−93.6%Reduced
BNP Paribas Arbitrage, SA37,744$392.9K0.00%+37,744New
Virtu Financial LLC53,686$561.0K0.02%+53,686New
CSS LLC57,143$594.9K0.03%00.0%Unchanged
Clear Street Group Inc.77,452$806.3K0.00%+73,257+1,746.3%Added
Baird Financial Group, Inc.78,500$819.1K0.00%00.0%Unchanged
K2 Principal Fund, L.P.87,900$915.0K0.10%00.0%Unchanged
Lineage Point Capital LP95,895$1.00M0.24%+95,895New
Gritstone Asset Management LLC99,081$1.03M1.10%00.0%Unchanged
MMCAP International Inc. SPC125,000$1.30M0.11%00.0%Unchanged
Wolverine Asset Management LLC134,280$1.40M0.02%−221,074−62.2%Reduced
Readystate Asset Management LP148,734$1.55M0.09%+1,200+0.8%Added
DLD Asset Management, LP150,000$1.56M0.16%−50,000−25.0%Reduced
Schonfeld Strategic Advisors LLC173,515$1.81M0.01%00.0%Unchanged
L1 Global Manager Pty Ltd200,000$2.08M1.68%00.0%Unchanged
O'Connor Alternative Investments LLC200,000$2.09M0.11%+200,000New
Berkley W R Corp208,065$2.17M0.12%−20,141−8.8%Reduced
Verition Fund Management LLC231,470$2.42M0.02%00.0%Unchanged
Aristeia Capital LLC250,000$2.60M0.06%00.0%Unchanged
Whitebox Advisors LLC250,000$2.60M0.04%00.0%Unchanged
Shaolin Capital Management LLC270,783$2.82M0.12%00.0%Unchanged
Quarry LP285,000$2.97M0.60%+285,000New
Centiva Capital, LP285,515$2.98M0.14%00.0%Unchanged
Meteora Capital, LLC295,612$3.08M0.23%−422,821−58.9%Reduced
Mint Tower Capital Management B.V.300,000$3.12M0.31%00.0%Unchanged
Millennium Management LLC307,985$3.21M0.00%00.0%Unchanged
Goldman Sachs Group Inc327,450$3.41M0.00%+3,596+1.1%Added
Periscope Capital Inc.352,880$3.68M0.64%−95,220−21.2%Reduced
J. Goldman & Co LP369,778$3.85M0.18%+369,778New
Commonwealth of Pennsylvania Public School Empls Retrmt Sys400,000$4.17M0.02%00.0%Unchanged
RLH Capital LLC400,907$4.18M2.13%+400,907New
Rivernorth Capital Management, LLC427,500$4.45M0.22%−20,250−4.5%Reduced
Moore Capital Management, LP450,000$4.68M0.17%00.0%Unchanged
Picton Mahoney Asset Management500,000$5.21M0.05%00.0%Unchanged
Jain Global LLC500,000$5.22M0.07%00.0%Unchanged
Sculptor Capital LP600,646$6.25M0.07%00.0%Unchanged
Toronto Dominion Bank650,000$6.77M0.01%+499,998+333.3%Added
Radcliffe Capital Management, L.P.661,337$6.90M0.52%+3,015+0.5%Added
Hudson Bay Capital Management LP700,000$7.32M0.04%00.0%Unchanged
Two Sigma Investments, LP725,000$7.55M0.01%00.0%Unchanged
Glazer Capital, LLC750,000$7.81M0.17%−114,303−13.2%Reduced
Alberta Investment Management Corp750,000$7.84M0.05%00.0%Unchanged
Governors Lane LP759,556$7.93M0.99%+939+0.1%Added
Ghisallo Capital Management LLC800,000$8.35M0.23%00.0%Unchanged
LMR Partners LLP850,000$8.85M0.08%00.0%Unchanged
Westchester Capital Management, LLC907,144$9.44M0.46%00.0%Unchanged
CNH Partners LLC920,672$9.58M0.16%−43,710−4.5%Reduced
Linden Advisors LP1,000,000$10.4M0.06%00.0%Unchanged
D. E. Shaw & Co., Inc.1,138,500$11.9M0.01%00.0%Unchanged
Magnetar Financial LLC1,300,000$13.6M0.14%00.0%Unchanged
Tenor Capital Management Co., L.P.1,500,000$15.6M0.24%00.0%Unchanged
Driehaus Capital Management LLC0$00.00%−573,083−100.0%Sold out
StoneX Group Inc.0$00.00%−50,613−100.0%Sold out
Warberg Asset Management LLC0$00.00%−10,000−100.0%Sold out
UBS Oconnor LLC––––Not filed