Archimedes Tech SPAC Partners III Co.

ARCI

Exchange: Nasdaq
Industry: Blank Checks
SEC CIK: 0002083910

SEC filings (opens in a new tab)

No open-market purchases or sales by Archimedes Tech SPAC Partners III Co. insiders were filed in the last 90 days; 52 institutions reported holding it in 13F filings for Q2 2026, worth $202.6M in total; no superinvestor holds it.

Other share classesARCIU ARCIW

Q1 2026 vs. Q4 2025

How the institutions holding Archimedes Tech SPAC Partners III Co. changed between Q4 2025 and Q1 2026.

All holders in Q1 2026 All holders in Q4 2025

13F holders of ARCI: Q4 2025 compared with Q1 2026
Measure	Q4 2025	Q1 2026	Change
Holders	0	40	+40
Shares	0	15.6M	+15.6M
Value	$0	$153.3M	+$153.3M

New holders (40)

Institutions that held Archimedes Tech SPAC Partners III Co. at the end of Q1 2026 but not at the end of Q4 2025.

Institutions new to ARCI in Q1 2026
Institution	Shares	Value	% of portfolio
Adage Capital Partners GP, L.L.C.	1,800,000	$17.7M	0.03%
Linden Advisors LP	1,200,000	$11.8M	0.07%
Magnetar Financial LLC	1,200,000	$11.8M	0.12%
Tenor Capital Management Co., L.P.	1,000,000	$9.85M	0.15%
Governors Lane LP	1,000,000	$9.85M	1.23%
Sona Asset Management (US) LLC	800,000	$7.88M	0.30%
Verition Fund Management LLC	750,000	$7.39M	0.07%
Healthcare of Ontario Pension Plan Trust Fund	550,000	$5.42M	0.01%
Shaolin Capital Management LLC	540,454	$5.32M	0.22%
Glazer Capital, LLC	504,602	$4.97M	0.11%
Polar Asset Management Partners Inc.	500,000	$4.92M	0.12%
Moore Capital Management, LP	500,000	$4.92M	0.18%
Meteora Capital, LLC	483,740	$4.76M	0.35%
D. E. Shaw & Co., Inc.	425,000	$4.19M	0.00%
Radcliffe Capital Management, L.P.	414,297	$4.08M	0.31%
Periscope Capital Inc.	409,001	$4.03M	0.70%
Hudson Bay Capital Management LP	300,000	$2.96M	0.02%
K2 Principal Fund, L.P.	299,536	$2.95M	0.31%
Two Sigma Investments, LP	273,791	$2.70M	0.00%
HBK Investments L P	250,004	$2.46M	0.03%
Ghisallo Capital Management LLC	250,000	$2.46M	0.07%
Berkley W R Corp	248,000	$2.44M	0.13%
Clear Street Group Inc.	240,763	$2.37M	0.01%
683 Capital Management, LLC	200,000	$1.97M	0.18%
Vivaldi Asset Management, LLC	200,000	$1.97M	0.10%
DLD Asset Management, LP	170,000	$1.67M	0.17%
Mint Tower Capital Management B.V.	150,000	$1.48M	0.15%
Alpine Global Management, LLC	150,000	$1.48M	0.22%
StoneX Group Inc.	109,745	$1.08M	0.06%
Whitebox Advisors LLC	100,000	$985.0K	0.01%
Context Capital Management, LLC	100,000	$985.0K	0.02%
Toronto Dominion Bank	95,398	$939.7K	0.00%
Virtu Financial LLC	90,734	$894.0K	0.04%
JPMorgan Chase & Co	87,664	$861.7K	0.00%
L1 Global Manager Pty Ltd	75,000	$738.8K	0.60%
Parallax Volatility Advisers, L.P.	50,000	$494.5K	0.02%
Deltec Asset Management LLC	35,000	$344.8K	0.06%
Wolverine Asset Management LLC	10,087	$99.4K	0.00%
Royal Bank of Canada	2,700	$27.0K	0.00%
Morgan Stanley	17	$167	0.00%

Sold out (0)

Institutions that held Archimedes Tech SPAC Partners III Co. at the end of Q4 2025 and filed for Q1 2026 without it.

None.