Archimedes Tech SPAC Partners ATII Institutional Ownership

NASDAQ ATII

$7.22 -1.33 (-15.51%)

As of: Oct 20, 2026 · 10:42 AM EDT

Institutions by Trading Activity

51 Institutions

Increased 16 31.4%

Unchanged 12 23.5%

Reduced 23 45.1%

Ownership Statistics

13F · as of 30 Jun, 2026

Institutional Ownership

59.50%

▼-23.61 pp QoQ

Shares Held by Institutions

17.61Mn

of 29.59Mn outstanding

▼-20.64% QoQ

Shares Outstanding

29.59Mn

11.98Mn held outside 13F filers

Institutional Investors

filed 13F for Jun 2026

▼-3 vs prior quarter

Net Shares Added (QoQ)

-4.58Mn

distributed since last quarter

Value of Holdings

$156.00Mn

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

Updated Oct 5, 2026

Archimedes Tech SPAC Partners II Co. (NASDAQ:ATII) appeared in the 13F filings of 51 institutional investors for the quarter ended June 30, 2026.

Collectively, these holders controlled 59.50% of Archimedes Tech SPAC Partners' outstanding shares in Q2 2026, down from 83.11% in Q1 2026.
Total shares held in Archimedes Tech SPAC Partners fell 20.64% versus Q1 2026, while the number of holders rose 27.50% versus Q2 2025.
Among the 51 holders of Archimedes Tech SPAC Partners, 16 added to their positions, 23 reduced their stakes and 12 left their positions unchanged.
Altogether, institutional holders owned 17.61Mn ATII shares at the end of Q2 2026, down 4.58Mn from the prior quarter and down 3.36Mn from a year earlier.
As of June 30, 2026, Tenor Capital Management Co., L.P. held the largest stake in Archimedes Tech SPAC Partners with 1.37Mn shares, or 4.62% of shares outstanding.
The largest position increases in ATII for Q2 2026 were by K2 Principal Fund, L.P. (+438.33K shares), Citadel Advisors LLC (+239.89K shares) and DLD Asset Management, LP (+45.45K shares).
On the other side, among holders that kept a position in Archimedes Tech SPAC Partners, the largest reductions in Q2 2026 came from Glazer Capital, LLC (-699.9K shares), Toronto Dominion Bank (-567.45K shares), LMR Partners LLP (-371.02K shares), Alberta Investment Management Corp (-350K shares) and AQR Arbitrage LLC (-330.41K shares).
Business Quant data shows the 10 biggest positions in Archimedes Tech SPAC Partners as of Q2 2026 were held by Tenor Capital Management Co., L.P. (1.37Mn shares), Fort Baker Capital Management LP (1.33Mn shares), Magnetar Financial LLC (1.3Mn shares), D. E. Shaw & Co., Inc. (1.14Mn shares), Decagon Asset Management LLP (937.83K shares), Linden Advisors LP (848.27K shares), Ghisallo Capital Management LLC (800K shares), Two Sigma Investments, LP (725K shares), Hudson Bay Capital Management LP (700K shares) and Shay Capital LLC (623.69K shares).

Form 13F Holdings

51 Institutional Holders

Report period 30 Jun, 2026

Total shares held 17.61Mn

Of outstanding 59.50%

#	Institution	CIK	Shares Held	% of Outstanding	Change (QoQ)	Change (%)	Value (USD)
1	TENOR CAPITAL MANAGEMENT Co., L.P.	0001346554	1,367,830	4.62%	▼132,170	-8.81%	$14.75Mn
2	Fort Baker Capital Management LP	0001688382	1,330,746	4.50%	▲1,330,746	0.00%	$14.35Mn
3	Magnetar Financial LLC	0001352851	1,297,302	4.38%	▼2,698	-0.21%	$13.98Mn
4	D. E. Shaw & Co., Inc.	0001009207	1,138,500	3.85%	0	0.00%	$12.27Mn
5	Decagon Asset Management LLP	0001950677	937,829	3.17%	▲937,829	0.00%	$10.11Mn
6	LINDEN ADVISORS LP	0001279396	848,273	2.87%	▼151,727	-15.17%	$9.14Mn
7	Ghisallo Capital Management LLC	0001825214	800,000	2.70%	0	0.00%	$8.62Mn
8	TWO SIGMA INVESTMENTS, LP	0001179392	725,000	2.45%	0	0.00%	$7.82Mn
9	Hudson Bay Capital Management LP	0001393825	700,000	2.37%	0	0.00%	$7.55Mn
10	Shay Capital LLC	0001723643	623,687	2.11%	▲623,687	0.00%	$6.72Mn
11	Governors Lane LP	0001644187	604,857	2.04%	▼154,699	-20.37%	$6.52Mn
12	AQR Arbitrage LLC	0001167456	590,262	1.99%	▼330,410	-35.89%	$6.36Mn
13	Sculptor Capital LP	0001054587	552,619	1.87%	▼48,027	-8.00%	$5.96Mn
14	K2 PRINCIPAL FUND, L.P.	0001461790	526,227	1.78%	▲438,327	+498.67%	$5.67Mn
15	LMR Partners LLP	0001578621	478,978	1.62%	▼371,022	-43.65%	$5.16Mn
16	Radcliffe Capital Management, L.P.	0001218275	478,061	1.62%	▼183,276	-27.71%	$5.15Mn
17	MOORE CAPITAL MANAGEMENT, LP	0001448574	450,000	1.52%	0	0.00%	$4.85Mn
18	Alberta Investment Management Corp	0001463559	400,000	1.35%	▼350,000	-46.67%	$4.31Mn
19	FNY Investment Advisers, LLC	0001742998	327,200	1.11%	▲327,200	0.00%	$3.53K
20	Mint Tower Capital Management B.V.	0001666606	300,000	1.01%	0	0.00%	$3.23K

Showing 1 to 20 of 51 holders