ATII · Archimedes Tech SPAC Partners II Co. · Holdings

$9.70 +2.53 (+35.29%)

Market Cap

$276.07M

29.59M

Volume · Oct 21 201.2K Avg daily vol (3M) 258.12K

Institutional ownership from SEC Form 13F filings. Investment managers with more than $100 million in U.S. equities must disclose their positions every quarter, within 45 days of quarter-end, so the holdings shown can lag the market by up to a quarter.

Use institutional holdings through the 13F API or MCP → See every holder of ATII: 13F, 13D and 13G, insiders and funds →

Institutional holdings are being reconciled with SEC filings. Holder totals and changes may be incomplete until reconciliation finishes.

Quarter:

Holders: 61

Total Value: $191,125,255

Total Shares: 26,253,670

Institutional Ownership Trend

6 quarters

Holder Concentration

Across 61 13F filers · Δ vs Mar 31, 2026

Top Holder

7.7%

+1.0 pts

Top 5

34.2%

+7.8 pts

Top 10

55.1%

+10.4 pts

HHI

417

Broadly held+97

Who Holds ATII

Last 6 quarters through Jun 30, 2026

Each kind of 13F filer's share of the common shares 13F filers report. Holder type comes from regulatory records, never the filer's name; style, turnover and horizon are measured from each filer's own 13F book. The quarter selector does not change this card.

Jun 30, 2026: 61 filers, like-for-like change -19.8%; actively managed books -19.7%; index-like books -34.2%.

Holder type	Share	Filers	Change	New	Exited
Registered adviser	64.6%	31	-20.0%	5	4
Exempt adviser	5.0%	2	-28.4%	0	0
Adviser	0.0%	0	-100.0%	0	2
Bank	0.5%	3	-89.3%	0	0
Insurer	0.0%	0	-100.0%	0	1
Non-US	5.6%	3	-40.4%	0	1
Holding company	0.8%	2	-37.4%	0	0
Broker-dealer	0.0%	0	—	0	0
Unknown	23.5%	20	+24.9%	9	4

Style	Share	Filers	Change	New	Exited
Index-like	0.9%	4	-34.2%	0	0
Systematic-like	19.5%	11	-7.2%	2	0
Concentrated	17.8%	6	+89.6%	4	2
Diversified active	61.8%	40	-33.5%	8	10
Not measured	0.0%	0	—	0	0
Unknown	0.0%	0	—	0	0

Turnover	Share	Filers	Change	New	Exited
Low turnover	1.4%	7	-58.1%	1	1
Medium turnover	51.0%	21	-22.5%	4	3
High turnover	46.2%	30	-8.6%	9	6
Unknown	1.3%	3	-73.7%	0	2
Not measured	0.0%	0	—	0	0

Holding horizon	Share	Filers	Change	New	Exited
Short horizon	49.9%	22	-19.8%	4	6
Medium horizon	19.2%	10	+14.1%	4	1
Long horizon	11.9%	16	-36.5%	2	1
Unknown	19.0%	13	-29.6%	4	4
Not measured	0.0%	0	—	0	0

13F book size	Share	Filers	Change	New	Exited
Under $1B	33.2%	19	+13.8%	8	4
$1B to $10B	45.0%	20	-28.1%	3	6
$10B to $100B	10.2%	10	-51.4%	2	2
$100B or more	11.6%	12	-2.9%	1	0
Not measured	0.0%	0	—	0	0

Client base	Share	Filers	Change	New	Exited
Individuals and high net worth	0.0%	1	new	1	0
Pooled investment vehicles	63.6%	28	-13.3%	4	2
Registered funds and BDCs	0.9%	2	-86.7%	0	1
Charitable organizations	0.0%	0	-100.0%	0	1
Diversified	0.0%	0	—	0	0
Other investment advisers	0.0%	0	—	0	0
Unknown	35.4%	30	-19.5%	9	8

Private funds	Share	Filers	Change	New	Exited
Hedge funds	65.3%	30	-16.8%	4	3
Real estate funds	0.0%	1	new	1	0
Private funds, type not stated	4.2%	1	-14.3%	0	0
No private funds	0.0%	1	-99.0%	0	1
Private equity funds	0.0%	0	—	0	0
Unknown	30.4%	28	-17.8%	9	8

Location	Share	Filers	Change	New	Exited
United States	78.7%	49	-21.3%	12	11
Outside the US	21.3%	12	-13.8%	2	1

How the mix is measured

Shares are 13F common shares restated to today's split basis; options and principal amounts are left out. The change compares only filers with a 13F in both quarters and keeps each filer in its bucket of the later quarter on both sides; a filer that continues under a new CIK is compared through its successor. Holder type comes from each filer's current regulatory profile; client base and private funds come from the Form ADV roster current at each quarter end (rosters from December 2019, so an earlier quarter reads Unknown). Style, turnover, horizon and book size are measured from each filer's 13F book in the newest measured quarter, and Not measured means none was. Actively managed books are those measured systematic-like, concentrated or diversified active.

Conviction and Crowding

51 13F filers, quarter ended Jun 30, 2026

Measured across every 13F filer's common-share book once the quarter's filing window closed. Crowding counts filers with high turnover or that advise private funds on Form ADV.

Conviction holders

3.92% of filers hold it in their top 10

Mar 31, 2026: 1

Holders above 5%

median weight 0.040%

Mar 31, 2026: 0

Crowding

54.0%

of shares outstanding, 98th percentile

Mar 31, 2026: 58.2%

Private-fund advisers

41.4%

of shares outstanding

Institutional ownership

59.5%

156.1% of the estimated free float above 100%: filers can report lent or client shares more than once

Top 10 holders

55.5%

of 13F shares, Herfindahl 0.042

Active holders

-20.4%

like-for-like share change of active filers

5% stakes on record

0 13D, 0 13G

How long holders have held it value-weighted 4.0 quarters

Under 1 year 25.5% 1 to 3 years 74.5% 3 years or more 0.000% Since coverage start 0.000%

Managers in the top fifth by current three-year FundScore alpha were net buyers of $0 (0 buying, 0 selling).

Estimated Holder Cost Basis

Quarter ended Jun 30, 2026, on that quarter's share basis

Estimated, never filed: each 13F buy is costed at its quarter's average traded price and each sale keeps the average cost, so this is what holders paid on average if they traded evenly through each quarter.

Estimated avg cost

$10.30

estimated per share

Mar 31, 2026: $10.12

Quarter-end price

$10.78

implied by 13F values

Estimated gain or loss

+4.7%

price against the estimated cost

Estimated at a loss

24.0%

of costed 13F value

Estimated cost covers 98.6% of the 13F shares; positions already held when a filer's 13F history starts, or bought in a quarter without a trusted average price, have no estimate.

Shared Holders

Companies ATII's active holders also own, quarter ended Jun 30, 2026

#	Company	Shared holders	Similarity
1	NHIC NewHold Investment Corp. III	3	0.387
2	VLOS Velos Acquisition I Corp.	3	0.387
3	ALDF Aldel Financial II Inc.	3	0.387
4	NTWO Newbury Street II Acquisition Corp	4	0.348
5	TVA Texas Ventures Acquisition III Corp	3	0.340
6	CLBR Colombier Acquisition Corp. III	4	0.303
7	POLE Andretti Acquisition Corp. II	3	0.297
8	CCII Cohen Circle Acquisition Corp. II	4	0.272
9	CEPV Cantor Equity Partners V, Inc.	4	0.261
10	NWAX New America Acquisition I Corp.	3	0.245

Shareholder Targets

13F filers that own its peers but not ATII, quarter ended Jun 30, 2026

Found through its holder-overlap peers: NHIC, VLOS, ALDF, NTWO, TVA, CLBR, POLE, CCII, CEPV, NWAX, BBCQ, RTAC, RNGT, EVAC, CEPF, RVMD, GEV, META, NVDA, AMZN. 6,798 filers in all.

#	Filer	In peers	Of book	Largest peers
1	BlackRock, Inc. Holding company, Index-like	$692,740,308,982 5 held	10.6%	NVDA, AMZN, META
2	VANGUARD CAPITAL MANAGEMENT LLC Registered adviser, Index-like	$562,952,114,168 5 held	12.0%	NVDA, AMZN, META
3	FMR LLC Holding company, Diversified active	$367,730,729,303 5 held	16.3%	NVDA, AMZN, META
4	STATE STREET CORP Bank, Index-like	$363,294,665,559 5 held	10.7%	NVDA, AMZN, META
5	VANGUARD PORTFOLIO MANAGEMENT LLC Registered adviser, Diversified active	$161,324,908,318 5 held	7.25%	NVDA, AMZN, META
6	Invesco Ltd. Adviser, Diversified active	$125,016,419,143 5 held	9.91%	NVDA, AMZN, META
7	NORGES BANK Non-US, Index-like	$121,578,016,535 5 held	12.1%	NVDA, AMZN, META
8	PRICE T ROWE ASSOCIATES INC /MD/ Registered adviser, Diversified active	$120,940,320,874 5 held	12.2%	NVDA, AMZN, META
9	Capital Research Global Investors Adviser, Diversified active	$91,646,444,910 4 held	12.7%	NVDA, AMZN, META
10	NORTHERN TRUST CORP Bank, Index-like	$88,610,954,452 5 held	10.7%	NVDA, AMZN, META

Fund Ownership of ATII by Fund Type

Registered funds' Form N-PORT reports for the quarter ended Jun 30, 2026

Index funds and index ETFs hold 0.00% of shares outstanding.

Fund type	Of shares outstanding	Change	Shares	Funds
Index funds	0.00%	0.00 pp	0	0
Index ETFs	0.00%	0.00 pp	0	0
Active ETFs	0.00%	0.00 pp	0	0
Active funds	0.00%	-1.71 pp	820	1
Unclassified	0.00%	0.00 pp	0	0
All registered funds	0.00%	-1.71 pp	820	1

How fund types are measured

Each fund series counts once, with its latest Form N-PORT report dated inside the quarter; only long share positions count, restated to today's split basis. The fund type is the series' latest Form N-CEN answer on or before the quarter end (the index-fund box and the exchange-traded flag), never its name. Unclassified funds have no usable N-CEN; unit investment trusts are among them, so index ownership is a floor. Funds sit inside their advisers' 13F reports, so these shares overlap the 13F figures and are never added to them.

Quarterly Activity

vs Mar 31, 2026

New

Increased

Decreased

Sold Out

Unchanged

New and Sold Out count only filers that reported a 13F for both quarters: a first-time filer's book is not a buy, and a fund that has not filed, or withheld its positions under confidential treatment, has not sold.

Holder count: +1

Institutional value: -17.2%

Shares held: -19.9%

Top Buyers

vs Mar 31, 2026

Institution	Added	Now Holds
Mid ARISTEIA CAPITAL, L.L.C.	+613,491	988,491
Small K2 PRINCIPAL FUND, L.P.	+479,150	806,945
Mega CITADEL ADVISORS LLC	+239,889	250,266
Mid Sculptor Capital LP	+102,173	702,819
Small DLD Asset Management, LP	+14,853	264,853

Top Sellers

vs Mar 31, 2026

Institution	Sold	Now Holds
Large TORONTO DOMINION BANK	−1,122,124	82,550
Mid GLAZER CAPITAL, LLC	−724,751	50,100
Small Shaolin Capital Management LLC	−512,972	257,811
Mid Linden Advisors LP	−508,551	1,352,411
Mid RIVERNORTH CAPITAL MANAGEMENT, LLC	−427,500	224,942

Top New Positions

vs Mar 31, 2026

Institution	Acquired	Value (USD)
Mid Fort Baker Capital Management LP	1,371,923	$14,345,441
Small Decagon Asset Management LLP	1,269,131	$10,109,796
Mid Shay Capital LLC	623,687	$6,723,345
Small FNY Investment Advisers, LLC	327,200	$3,527,216
Small SkyView Investment Advisors, LLC	182,495	$1,967,296

Top Sold-Out Positions

vs Mar 31, 2026

Institution	Previously Held	Last Value (USD)
Mid Westchester Capital Management, LLC	1,107,143	$9,443,367
Large PICTON MAHONEY ASSET MANAGEMENT	625,000	$5,205,000
Small RLH Capital LLC	448,289	$4,173,441
Large COMMONWEALTH OF PENNSYLVANIA PUBLIC SCHOOL EMPLS RETRMT SYS	400,000	$4,164,000
Mid J. Goldman & Co LP	369,778	$3,849,388

Filter: New 13 Increased 6 Reduced 30 Sold out 12 Unchanged 12

Holder type: Registered adviser 31 Exempt adviser 2 Bank 3 Non-US 3 Holding company 2 Unknown 20

Showing 89 of 89

All Common Calls Puts

Compact Export CSV

Holder

Value (USD)

% of 13F

TENOR CAPITAL MANAGEMENT Co., L.P.

$14,745,207

7.71%

1,367,830

Fort Baker Capital Management LP

$14,345,441

7.51%

1,330,746

Magnetar Financial LLC

$13,984,915

7.32%

1,297,302

D. E. Shaw & Co., Inc.

$12,273,030

6.42%

1,138,500

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
D. E. SHAW & CO, L.P.	1,138,500	$12,273,030	100.0%	Defined

Decagon Asset Management LLP

$10,109,796

5.29%

937,829

Linden Advisors LP

$9,144,382

4.78%

848,273

Ghisallo Capital Management LLC

$8,624,000

4.51%

800,000

TWO SIGMA INVESTMENTS, LP

$7,815,500

4.09%

725,000

Hudson Bay Capital Management LP

$7,546,000

3.95%

700,000

Shay Capital LLC

$6,723,345

3.52%

623,687

Governors Lane LP

$6,520,358

3.41%

604,857

AQR Arbitrage LLC

$6,363,024

3.33%

590,262

Sculptor Capital LP

$5,957,232

3.12%

552,619

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Sculptor Capital II LP joint	552,619	$5,957,232	100.0%	Sole

K2 PRINCIPAL FUND, L.P.

$5,672,727

2.97%

526,227

LMR Partners LLP

$5,163,382

2.70%

478,978

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
LMR PARTNERS (DIFC) Ltd	478,978	$5,163,382	100.0%	Sole

Radcliffe Capital Management, L.P.

$5,153,497

2.70%

478,061

MOORE CAPITAL MANAGEMENT, LP

$4,851,000

2.54%

450,000

Alberta Investment Management Corp

$4,312,000

2.26%

400,000

FNY Investment Advisers, LLC

$3,527,216

1.85%

327,200

Mint Tower Capital Management B.V.

$3,234,000

1.69%

300,000

CITADEL ADVISORS LLC

$2,697,867

1.41%

250,266

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Citadel Securities GP LLC	250,266	$2,697,867	100.0%	Defined

WHITEBOX ADVISORS LLC

$2,695,000

1.41%

250,000

Harraden Circle Investments, LLC

$2,529,645

1.32%

234,661

GOLDMAN SACHS GROUP INC

$2,210,870

1.16%

205,090

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
GOLDMAN SACHS & CO. LLC	205,090	$2,210,870	100.0%	Defined

L1 Global Manager Pty Ltd

$2,156,000

1.13%

200,000

ARISTEIA CAPITAL, L.L.C.

$2,156,000

1.13%

200,000

DLD Asset Management, LP

$2,106,983

1.10%

195,453

Jain Global LLC

$1,995,464

1.04%

185,108

SkyView Investment Advisors, LLC

$1,967,296

1.03%

182,495

Periscope Capital Inc.

$1,886,500

0.99%

175,000

Verition Fund Management LLC

$1,517,791

0.79%

140,797

MMCAP International Inc. SPC

$1,347,500

0.71%

125,000

TUDOR INVESTMENT CORP ET AL

$1,335,016

0.70%

123,842

CANTOR FITZGERALD, L. P.

$951,690

0.50%

88,283

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Cantor Fitzgerald & Co.	88,283	$951,690	100.0%	Defined

TORONTO DOMINION BANK

$889,889

0.47%

82,550

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
TD SECURITIES (USA) LLC	82,550	$889,889	100.0%	Defined

Baird Financial Group, Inc.

$846,230

0.44%

78,500

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
BAIRD TRUST Co	78,500	$846,230	100.0%	Defined

Shaolin Capital Management LLC

$821,123

0.43%

76,171

MILLENNIUM MANAGEMENT LLC

$747,959

0.39%

69,384

JPMORGAN CHASE & CO ATIIU

$587,510

0.31%

49,000

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
J.P. Morgan Securities LLC	49,000	$587,510	100.0%	Defined

JANE STREET GROUP, LLC ATIIU

$540,136

0.28%

45,049

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Jane Street Capital, LLC	45,030	$539,909	100.0%	Defined
Jane Street Global Trading, LLC	19	$227	0.0%	Defined

GLAZER CAPITAL, LLC

$540,078

0.28%

50,100

Schonfeld Strategic Advisors LLC

$539,000

0.28%

50,000

HRT FINANCIAL LP

$508,708

0.27%

47,190

Clear Street Group Inc.

$269,500

0.14%

25,000

BNP PARIBAS ARBITRAGE, SA

$256,456

0.13%

23,790

MIZUHO SECURITIES USA LLC

$209,875

0.11%

19,469

HIGHBRIDGE CAPITAL MANAGEMENT LLC

$188,617

0.10%

17,497

Clear Street Group Inc. ATIIU

$169,826

0.09%

14,164

READYSTATE ASSET MANAGEMENT LP

$135,051

0.07%

12,528

GEODE CAPITAL MANAGEMENT, LLC

$119,679

0.06%

11,102

EverSource Wealth Advisors, LLC

$91,630

0.05%

8,500

UBS Group AG ATIIU

$25,802

0.01%

2,152

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
UBS Securities LLC	2,152	$25,802	100.0%	Defined

UBS Group AG

$17,873

0.01%

1,658

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
UBS AG	49	$528	3.0%	Defined
UBS Securities LLC	1,609	$17,345	97.0%	Defined

MORGAN STANLEY

$377

0.00%

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
MORGAN STANLEY CAPITAL SERVICES, LLC	35	$377	100.0%	Defined

HIGHBRIDGE CAPITAL MANAGEMENT LLC ATIIW

$219

0.00%

109

Caitong International Asset Management Co., Ltd

$43

0.00%

TENOR CAPITAL MANAGEMENT Co., L.P. ATIIW

—

750,000

Periscope Capital Inc. ATIIW

—

40,000

HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND ATIIW

—

500,000

AQR Arbitrage LLC ATIIW

—

481,366

MOORE CAPITAL MANAGEMENT, LP ATIIW

—

225,000

D. E. Shaw & Co., Inc. ATIIW

—

287,500

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
D. E. SHAW & CO, L.P.	287,500	$0	—	Defined

K2 PRINCIPAL FUND, L.P. ATIIW

—

280,718

Lineage Point Capital LP ATIIW

—

35,771

RIVERNORTH CAPITAL MANAGEMENT, LLC ATIIW

—

224,942

Centiva Capital, LP ATIIW

—

31,450

SUSQUEHANNA INTERNATIONAL GROUP, LLP ATIIW

—

48,825

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
G1 EXECUTION SERVICES, LLC	48,825	$0	—	Other

Thomas J. Herzfeld Advisors, Inc. ATIIW

—

5,000

Decagon Asset Management LLP ATIIW

—

331,302

Alberta Investment Management Corp ATIIW

—

375,000

CSS LLC/IL ATIIW

—

151,718

Mint Tower Capital Management B.V. ATIIW

—

130,000

Alpine Global Management, LLC ATIIW

—

71,039

Fort Baker Capital Management LP ATIIW

—

41,177

Harraden Circle Investments, LLC ATIIW

—

1,131,600

MMCAP International Inc. SPC ATIIW

—

62,500

Hudson Bay Capital Management LP ATIIW

—

39,994

Magnetar Financial LLC ATIIW

—

437,600

WHITEBOX ADVISORS LLC ATIIW

—

125,000

DLD Asset Management, LP ATIIW

—

69,400

LMR Partners LLP ATIIW

—

613,701

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
LMR PARTNERS (DIFC) Ltd	613,701	$0	—	Sole

Schonfeld Strategic Advisors LLC ATIIW

—

30,000

Sculptor Capital LP ATIIW

—

150,200

This filing is a combination report: the position is filed across the managers below.

Manager	Shares	Value (USD)	% of position	Discretion
Sculptor Capital II LP joint	150,200	$0	—	Sole

Clear Street Group Inc. ATIIW

—

60,000

Shaolin Capital Management LLC ATIIW

—

181,640

ARISTEIA CAPITAL, L.L.C. ATIIW

—

788,491

MILLENNIUM MANAGEMENT LLC ATIIW

—

169,353

BNP PARIBAS ARBITRAGE, SA ATIIW

—

161,927

Linden Advisors LP ATIIW

—

504,138

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