ATOS Institutional Ownership & Shareholders
ATOSSA THERAPEUTICS INC (ATOS) is currently held by 31 institutional investors tracked by InsiderSet, with a combined reported market value of approximately $2.60M based on the latest available SEC Form 13F filings for the quarter ended June 30, 2026.
Vanguard Capital Management Llc is currently the largest disclosed institutional shareholder of ATOS tracked by InsiderSet, reporting ownership valued at approximately $698,172 in its June 30, 2026 SEC Form 13F filing. Based on current market prices and the latest disclosed share count, the position is now estimated to be worth approximately $832,018.1, representing an estimated gain of +19.17% since the filing period.
The top 10 institutional shareholders tracked on this page collectively account for approximately 96% of the total disclosed ATOS value among the investors covered in this analysis. Major shareholders include Vanguard Capital Management Llc, Ameriprise Financial Inc, Blackrock, Inc., and several other long-term asset managers with concentrated positions in ATOSSA THERAPEUTICS INC (ATOS).
This page ranks the largest institutional ATOS shareholders using publicly disclosed SEC Form 13F data, including reported values, estimated current holding values, portfolio allocation percentages, ownership concentration metrics, and historical holding changes across major hedge funds and investment firms.
Institutional Holders
31
Total Reported Value
$2.60M
Largest Holder
Vanguard Capital Management Llc
Largest Position
$698,172
Insider Transactions (90d)
0
Latest Filing Quarter
Q2 2026
New Institutional Positions
79
Funds Exiting Positions
1
| Name | Investor/Manager | Portfolio % | Quantity | Reported Balance | Current Estimated Value | Gain/loss Since Filing | Estimated Portfolio Performance |
|---|---|---|---|---|---|---|---|
| Vanguard Capital Management Llc | 0.00% | 361,747 | $698,172 | $832,018 | +$133,846 | +19.17% | |
| Ameriprise Financial Inc | 0.00% | 258,234 | $498,392 | $593,938 | +$95,546 | +19.17% | |
| Blackrock, Inc. | 0.00% | 164,358 | $317,211 | $378,023 | +$60,812 | +19.17% | |
| Renaissance Technologies LLC | Jim Simons | 0.00% | 132,043 | $254,843 | $303,699 | +$48,856 | +19.17% |
| Geode Capital Management, Llc | 0.00% | 92,382 | $178,343 | $212,479 | +$34,136 | +19.14% | |
| Ubs Group Ag | 0.00% | 82,620 | $159,456 | $190,026 | +$30,570 | +19.17% | |
| Jane Street Group, Llc | 0.00% | 56,602 | $109,242 | $130,185 | +$20,943 | +19.17% | |
| Vanguard Fiduciary Trust Co | 0.00% | 52,583 | $101,485 | $120,941 | +$19,456 | +19.17% | |
| Millennium Management Llc | 0.00% | 46,508 | $89,760 | $106,968 | +$17,208 | +19.17% | |
| State Street Corp | 0.00% | 39,761 | $76,739 | $91,450 | +$14,711 | +19.17% | |
| Northern Trust Corp | 0.00% | 20,249 | $39,081 | $46,573 | +$7,492 | +19.17% | |
| Susquehanna International Group, Llp | 0.00% | 15,574 | $30,058 | $35,820 | +$5,762 | +19.17% | |
| Morgan Stanley | 0.00% | 12,345 | $23,825 | $28,393 | +$4,568 | +19.18% | |
| Vanguard Global Advisers, Llc | 0.00% | 3,089 | $5,962 | $7,105 | +$1,143 | +19.17% | |
| Royal Bank Of Canada | 0.00% | 1,994 | $4,000 | $4,586 | +$586 | +14.65% | |
| Jones Financial Companies Lllp | 0.00% | 2,061 | $3,875 | $4,740 | +$865 | +22.33% | |
| Osaic Holdings, Inc. | 0.00% | 587 | $1,131 | $1,350 | +$219 | +19.37% | |
| Rydar Equities, Inc. | 0.00% | 333 | $819 | $766 | -$53 | -6.48% | |
| Jpmorgan Chase & Co | 0.00% | 390 | $772 | $897 | +$125 | +16.19% | |
| Rockefeller Capital Management L.P. | 0.00% | 333 | $643 | $766 | +$123 | +19.11% | |
| Wells Fargo & Company/Mn | 0.00% | 228 | $440 | $524 | +$84 | +19.18% | |
| Sbi Securities Co., Ltd. | 0.00% | 148 | $289 | $340 | +$51 | +17.79% | |
| Td Waterhouse Canada Inc. | 0.00% | 103 | $230 | $237 | +$7 | +3.00% | |
| Harbour Investments, Inc. | 0.00% | 110 | $212 | $253 | +$41 | +19.34% | |
| Bnp Paribas Financial Markets | 0.00% | 87 | $168 | $200 | +$32 | +19.11% | |
| Group One Trading Llc | 0.00% | 54 | $104 | $124 | +$20 | +19.42% | |
| Ifp Advisors, Inc | 0.00% | 29 | $57 | $67 | +$10 | +17.02% | |
| Caitong International Asset Management Co., Ltd | 0.00% | 8 | $16 | $18 | +$2 | +15.00% | |
| Napier Financial, Llc | 0.00% | 6 | $12 | $14 | +$2 | +15.00% | |
| Bogart Wealth, Llc | 0.00% | 5 | $10 | $12 | +$2 | +15.00% | |
| Clearstead Advisors, Llc | 0.00% | 4 | $8 | $9 | +$1 | +15.00% |
Frequently asked questions about ATOS
Who are the largest institutional holders of ATOS?
The largest institutional holders of ATOS reported in the latest SEC Form 13F filings include Vanguard Capital Management Llc, Ameriprise Financial Inc, Blackrock, Inc., Renaissance Technologies LLC, and Geode Capital Management, Llc. InsiderSet ranks institutional holders by their latest reported ATOS position.
What is ATOS institutional ownership?
This page tracks ATOS positions reported by institutional investment managers through SEC Form 13F. ATOSSA THERAPEUTICS INC (ATOS) institutional ownership on InsiderSet reflects disclosed 13F holdings among the managers we analyze, not every shareholder of the stock.
How many institutions own ATOS?
InsiderSet currently tracks 31 institutional managers reporting ATOS holdings in the latest available 13F data. This count reflects institutions included in the SEC Form 13F filings analyzed by InsiderSet and should not be interpreted as the total number of ATOS shareholders.
How much ATOS stock do institutions own?
Institutional investment managers disclosed approximately $2.60M in ATOS holdings for Q2 2026. This figure is reported 13F value as of the filing period, not necessarily today's market value.
When was ATOS institutional ownership last updated?
The latest ATOS institutional ownership data on InsiderSet is based on SEC Form 13F filings for the quarter ended June 30, 2026. Form 13F filings are generally reported after the quarter ends, so the holdings shown represent the latest publicly disclosed positions rather than real-time institutional holdings.
Are institutional ATOS holdings real-time?
No. Form 13F data is not real-time. It represents positions reported by institutional investment managers as of the end of the reporting quarter. An institution may have changed its ATOS position after the reporting date.
Are institutions buying or selling ATOS?
Institutional buying and selling can be analyzed by comparing ATOS positions across consecutive 13F reporting periods. InsiderSet's ATOS Ownership Changes page shows institutions that increased, reduced, initiated, or exited positions based on reported 13F holdings. View ATOS ownership changes.
How has ATOS institutional ownership changed over time?
InsiderSet tracks ATOS institutional holdings across multiple 13F reporting periods, allowing investors to compare institutional holder counts, reported value, and reported shares over time.