Altimmune Ownership

Who are the major shareholders and have insiders been buying or selling?

Recent Insider Transactions

NasdaqGM:ALT Recent Insider Transactions by Companies or Individuals
Date	Value	Name	Entity	Shares	Max Price
13 Aug 26	BuyUS$44,250	Jerome Durso	Individual	15,000	US$2.95
06 Apr 26	BuyUS$31,350	John Gill	Individual	9,200	US$3.41
01 Apr 26	BuyUS$47,100	Jerome Durso	Individual	15,000	US$3.14
01 Apr 26	BuyUS$31,499	Gregory Weaver	Individual	10,000	US$3.15
06 Mar 26	BuyUS$70,790	Jerome Durso	Individual	20,000	US$3.54
06 Mar 26	BuyUS$17,700	Gregory Weaver	Individual	5,000	US$3.54
08 Jan 26	BuyUS$20,410	Wayne Pisano	Individual	5,000	US$4.08
05 Jan 26	BuyUS$2,118	Catherine Sohn	Individual	500	US$4.24
29 Dec 25	BuyUS$2,003	Diane Jorkasky	Individual	527	US$3.80
23 Dec 25	BuyUS$51,250	John Gill	Individual	12,500	US$4.10
22 Dec 25	BuyUS$51,569	Jerome Durso	Individual	12,500	US$4.13

Insider Trading Volume

Insider Buying: ALT insiders have bought more shares than they have sold in the past 3 months.

Ownership Breakdown

What is the ownership structure of ALT?
Owner Type	Number of Shares	Ownership Percentage
Individual Insiders	876,028	0.45%
VC/PE Firms	29,417,221	15.1%
General Public	57,594,598	29.6%
Institutions	106,629,854	54.8%

Dilution of Shares: Shareholders have been substantially diluted in the past year, with total shares outstanding growing by 120.4%.

Top Shareholders

Top 25 shareholders own 63.86% of the company

Ownership	Name	Shares	Current Value	Change %	Portfolio %
10.5%	BlackRock, Inc.	20,385,284	US$59.9m	59.3%	no data
9.98%	Deep Track Capital, LP	19,417,221	US$57.1m	0%	0.82%
6.22%	State Street Investment Management	12,098,540	US$35.6m	69.3%	no data
5.14%	TCG Crossover Management, LLC	10,000,000	US$29.4m	0%	0.65%
4.87%	Vanguard Capital Management, LLC	9,470,753	US$27.8m	45.1%	no data
3.77%	Vanguard Portfolio Management, LLC	7,330,265	US$21.6m	36.2%	no data
3.52%	Marshall Wace LLP	6,841,055	US$20.1m	70.3%	0.02%
3.44%	Viking Global Investors LP	6,700,000	US$19.7m	0%	0.05%
3.34%	RA Capital Management, L.P.	6,500,000	US$19.1m	0%	0.19%
2.58%	Geode Capital Management, LLC	5,011,314	US$14.7m	61.3%	no data
1.68%	Millennium Management LLC	3,258,191	US$9.6m	1,470%	0.01%
1.36%	Alyeska Investment Group, L.P.	2,644,600	US$7.8m	0%	0.02%
1.27%	Two Sigma Investments, LP	2,478,900	US$7.3m	95.8%	0.01%
1.23%	Teachers Insurance and Annuity Association-College Retirement Equities Fund	2,397,668	US$7.0m	3.07%	no data
0.82%	Northern Trust Global Investments	1,599,226	US$4.7m	60.5%	no data
0.68%	Susquehanna International Group, LLP	1,325,956	US$3.9m	-11.9%	no data
0.61%	The Goldman Sachs Group, Inc.	1,185,705	US$3.5m	0%	no data
0.45%	UBS Asset Management AG	870,539	US$2.6m	-4.22%	no data
0.38%	FMR LLC	748,782	US$2.2m	11.1%	no data
0.37%	D. E. Shaw & Co., L.P.	727,001	US$2.1m	-45.9%	no data
0.35%	BNY Asset Management	689,713	US$2.0m	66.8%	no data
0.34%	Tang Capital Management, LLC	666,022	US$2.0m	-68.8%	0.08%
0.34%	Point72 Asset Management, L.P.	665,289	US$2.0m	0%	no data
0.33%	Dimensional Fund Advisors LP	639,436	US$1.9m	-38.9%	no data
0.29%	Bank of America Corporation	570,203	US$1.7m	49.6%	no data

Company Analysis and Financial Data Status

Data	Last Updated (UTC time)
Company Analysis	2026/08/16 01:53
End of Day Share Price	2026/08/14 00:00
Earnings	2026/06/30
Annual Earnings	2025/12/31

Data Sources

The data used in our company analysis is from S&P Global Market Intelligence LLC. The following data is used in our analysis model to generate this report. Data is normalised which can introduce a delay from the source being available.

Package	Data	Timeframe	Example US Source ^*
Company Financials	10 years	Income statement Cash flow statement Balance sheet	SEC Form 10-K SEC Form 10-Q
Analyst Consensus Estimates	+3 years	Forecast financials Analyst price targets	Analyst Research Reports Blue Matrix
Market Prices	30 years	Stock prices Dividends, Splits and Actions	ICE Market Data SEC Form S-1
Ownership	10 years	Top shareholders Insider trading	SEC Form 4 SEC Form 13D
Management	10 years	Leadership team Board of directors	SEC Form 10-K SEC Form DEF 14A
Key Developments	10 years	Company announcements	SEC Form 8-K

^* Example for US securities, for non-US equivalent regulatory forms and sources are used.

Unless specified all financial data is based on a yearly period but updated quarterly. This is known as Trailing Twelve Month (TTM) or Last Twelve Month (LTM) Data. Learn more.

Analysis Model and Snowflake

Details of the analysis model used to generate this report is available on our Github page, we also have guides on how to use our reports and tutorials on Youtube.

Learn about the world class team who designed and built the Simply Wall St analysis model.

Industry and Sector Metrics

Our industry and section metrics are calculated every 6 hours by Simply Wall St, details of our process are available on Github.

Analyst Sources

Altimmune, Inc. is covered by 18 analysts. 9 of those analysts submitted the estimates of revenue or earnings used as inputs to our report. Analysts submissions are updated throughout the day.

Analyst	Institution
Eliana Merle	Barclays
Mayank Mamtani	B. Riley Securities, Inc.
William Wood	B. Riley Securities, Inc.