Archimedes Tech SPAC Partners ATII Institutional Ownership

NASDAQ ATII

$10.66 +0.01 (+0.09%)

At close: Aug 26, 2026 · 4:00 PM EDT

Institutions by Trading Activity

54 Institutions

Increased 15 27.8%

Unchanged 27 50.0%

Reduced 12 22.2%

Ownership Statistics

13F · as of 31 Mar, 2026

Institutional Ownership

109.34%

▼-5.15 pp QoQ

Shares Held by Institutions

22.19Mn

of 20.29Mn outstanding

▼-0.94% QoQ

Shares Outstanding

20.29Mn

-1.90Mn held outside 13F filers

Institutional Investors

filed 13F for Mar 2026

▲+6 vs prior quarter

Net Shares Added (QoQ)

-211.41K

distributed since last quarter

Value of Holdings

$236.28Mn

reported market value

Shares Owned by Institutions

Shares held % of outstanding

Latest —

Average ownership —

Peak ownership —

Shares Purchased/Sold by Institutions

Accumulated Distributed

Latest quarter —

Net over range —

Accumulating quarters —

Ownership Summary

Quarter ending 31 Mar, 2026

Archimedes Tech SPAC Partners II Co. (NASDAQ:ATII) appears in 54 institutional 13F filings for the quarter ending March 2026.

They owned 109.3% of outstanding stock in March 2026, down from 114.5% the prior quarter.
They decreased total shares held in Archimedes Tech SPAC Partners by -0.94% from last quarter, and the number of investors in ATII stayed flat annually.
Of these 54 holders, 15 added to their stakes in Archimedes Tech SPAC Partners, 12 trimmed positions, and 27 made no changes.
Altogether, these fund groups held 22.19Mn shares in ATII by March 2026, down by 211.4K shares quarter on quarter, and with no net change year over year.
As of March 31, 2026, the biggest holder of Archimedes Tech SPAC Partners is TENOR CAPITAL MANAGEMENT Co., L.P. at 1.5Mn shares, representing 7.39% of shares outstanding.
The most significant purchases of ATII for the quarter ending March 2026 came from Toronto Dominion Bank (500.0K), RLH Capital LLC (400.91K), J. Goldman & Co LP (369.78K), Quarry LP (285.0K), O'Connor Alternative Investments LLC (200.0K).
Top sellers of ATII stock for the quarter ending March 2026 included Alberta Investment Management Corp (750.0K), METEORA CAPITAL, LLC (422.82K), Goldman Sachs Group Inc (320.26K), MIZUHO SECURITIES USA LLC (284.36K), WOLVERINE ASSET MANAGEMENT LLC (221.07K).
Business Quant data shows the 10 biggest positions in Archimedes Tech SPAC Partners as of March 2026 are held by TENOR CAPITAL MANAGEMENT Co., L.P. (1.5Mn), Magnetar Financial LLC (1.3Mn), D. E. Shaw & Co., Inc. (1.14Mn), LINDEN ADVISORS LP (1.0Mn), AQR Arbitrage LLC (920.67K), Westchester Capital Management, LLC (907.14K), LMR Partners LLP (850.0K), Ghisallo Capital Management LLC (800.0K), Governors Lane LP (759.56K), GLAZER CAPITAL, LLC (750.0K).

Form 13F Holdings

54 Institutional Holders

Report period 31 Mar, 2026

Total shares held 22.19Mn

Of outstanding 109.34%

#	Institution	CIK	Shares Held	% of Outstanding	Change (QoQ)	Change (%)	Value (USD)
1	TENOR CAPITAL MANAGEMENT Co., L.P.	0001346554	1,500,000	7.39%	0	0.00%	$15.62Mn
2	Magnetar Financial LLC	0001352851	1,300,000	6.41%	0	0.00%	$13.57Mn
3	D. E. Shaw & Co., Inc.	0001009207	1,138,500	5.61%	0	0.00%	$11.90Mn
4	LINDEN ADVISORS LP	0001279396	1,000,000	4.93%	0	0.00%	$10.44Mn
5	AQR Arbitrage LLC	0001167456	920,672	4.54%	▼43,710	-4.53%	$9.58Mn
6	Westchester Capital Management, LLC	0001512805	907,144	4.47%	0	0.00%	$9.44Mn
7	LMR Partners LLP	0001578621	850,000	4.19%	0	0.00%	$8.85Mn
8	Ghisallo Capital Management LLC	0001825214	800,000	3.94%	0	0.00%	$8.35Mn
9	Governors Lane LP	0001644187	759,556	3.74%	▲939	+0.12%	$7.93Mn
10	GLAZER CAPITAL, LLC	0001076809	750,000	3.70%	▼114,303	-13.22%	$7.81K
10	Alberta Investment Management Corp	0001463559	750,000	3.70%	▼750,000	-50.00%	$7.84Mn
11	TWO SIGMA INVESTMENTS, LP	0001179392	725,000	3.57%	0	0.00%	$7.55Mn
12	Hudson Bay Capital Management LP	0001393825	700,000	3.45%	0	0.00%	$7.32Mn
13	Radcliffe Capital Management, L.P.	0001218275	661,337	3.26%	▲3,015	+0.46%	$6.90Mn
14	Toronto Dominion Bank	0000947263	650,000	3.20%	▲499,998	+333.33%	$6.77Mn
15	Sculptor Capital LP	0001054587	600,646	2.96%	0	0.00%	$6.25Mn
16	PICTON MAHONEY ASSET MANAGEMENT	0001539041	500,000	2.46%	0	0.00%	$5.21Mn
16	Jain Global LLC	0002024579	500,000	2.46%	0	0.00%	$5.22Mn
17	MOORE CAPITAL MANAGEMENT, LP	0001448574	450,000	2.22%	0	0.00%	$4.68Mn
18	RIVERNORTH CAPITAL MANAGEMENT, LLC	0001447578	427,500	2.11%	▼20,250	-4.52%	$4.45Mn

Showing 1 to 20 of 54 holders