SEC ownership of Altimmune, Inc.

Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001326190.

Comparable stake leader

Deep Track Capital, LP

Disclosed value leader

TCG Crossover GP II, LLC

Comparable rows

50/50

Latest evidence

24 Apr 2026

Top shareholders Insider holders Latest transactions

Public ticker: ALT on Nasdaq
Parsed ownership sources: 13D/G and 13F
Source: Parsed SEC ownership filingsUse: Compare filing families carefully
Largest SEC-reported holder: Deep Track Capital, LP
Ranking: Comparable ownership first, then disclosed value
Comparable ownership rows: 50 of 50
Meaning: Rows with safely comparable ownership %
Latest 13D/G holder: Deep Track Capital, LP
Source: Latest parsed Schedule 13D/G stake
Latest parsed ownership date: 24 Apr 2026
Freshness: Most recent filing date in this holder set
Issuer CIK: 0001326190
Issuer location: Gaithersburg, MD

Ownership snapshot

Top shareholders of Altimmune, Inc. (13F + 13D/G + 3/4/5)

Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.

Comparable stake leader

Deep Track Capital, LP

Disclosed value leader

TCG Crossover GP II, LLC

Comparable rows

50/50

Latest evidence

24 Apr 2026

13D/G 13F Lead comparable stake: 10% 13D/G row: Deep Track Capital, LP Showing 1-8 of 50 holder rows.

Quick read

Deep Track Capital, LP leads the comparable SEC ownership view at 10%.

50 of 50 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.

Open SEC evidence Opens Deep Track Capital, LP's linked filing trail.

Comparable ownership Top 5

Deep Track Capital, LP 10%

TCG Crossover GP II, LLC 9.8%

BlackRock, Inc. 7.6%

VIKING GLOBAL INVESTORS LP 6.7%

RA CAPITAL MANAGEMENT, L.P. 6.5%

Ownership % is shown only when SEC disclosures are safely comparable across share classes.

Detailed SEC evidence table Showing 1-8 of 50 holder rows

Holder	Evidence	Ownership %	Position	12M Net Δ	As of
Deep Track Capital, LP	13D/G 13D/G	10%	$59,805,041 19,417,221 shares	$0	23 Apr 2026
TCG Crossover GP II, LLC	13D/G Chen Yu 13D/G	9.8%	$67,600,000 20,000,000 shares	$0	24 Apr 2026
BlackRock, Inc.	13F 13D/G Company 13F 13D/G	7.6% from 13D/G	$39,409,453 12,795,277 shares	—	31 Mar 2026
VIKING GLOBAL INVESTORS LP	13D/G 13D/G	6.7%	$45,292,000 13,400,000 shares	$0	24 Apr 2026
RA CAPITAL MANAGEMENT, L.P.	13D/G 13D/G	6.5%	$43,940,000 13,000,000 shares	$0	24 Apr 2026
STATE STREET CORP	13D/G 13F STATE STREET CORPORATION · Company 13D/G 13F	5.5%	$24,151,959 7,145,550 shares	$0	31 Mar 2026
AMERIPRISE FINANCIAL INC	13D/G 13F Company 13D/G 13F	1.9%	$7,306,296 1,443,932 shares	-$19,283,488	31 Mar 2025
TANG CAPITAL MANAGEMENT LLC	13D/G 13F Company 13D/G 13F	0.3%	$2,251,154 666,022 shares	$0	31 Mar 2026

How to read this table

Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.

Forms 3/4/5 flow

Insider trading overview

Net insider flow leans to buying over the last 12 months. Net value: +$325,788.

Buys

$325,788

Insiders: 6

Sells

Insiders: 0

Net

+$325,788

Shares: +90,227

Window

Last 12 months

4 rolling buckets

Buy value Sell value

Shares: 90,227 Shares: 0

Window (months)	Buy shares	Buy value	Sell value	Net value
0-3	0	$0	$0	$0
3-6	59,200	$198,439	$0	+$198,439
6-9	31,027	$127,349	$0	+$127,349
9-12	0	$0	$0	$0

Reporting owners

Insider holders from Forms 3/4/5

Showing 1-20 of 20 reporting-owner rows connected to Altimmune, Inc.. Open a relationship link for the CIK-to-CIK filing trail.

Rows

Largest Forms 3/4/5 holder

Vipin K. Garg

Net 12M change

+$325,789

Latest report

01 May 2026

Name	Relationship	Holdings Value	Past Year Net Change	Change %	Valuation	Report Date
Vipin K. Garg	Director	$2,487,141			Mixed	30 Jan 2026
M. Scot Roberts	Chief Scientific Officer	$589,541			Mixed	26 Feb 2026
Richard I. Eisenstadt	Chief Financial Officer	$441,118			Mixed	30 Jan 2024
Raymond M. Jordt	Chief Business Officer	$405,012			Mixed	31 Jan 2026
David Drutz	Director	$382,005			Filing P/S	19 Aug 2024
Matthew Scott Harris	Chief Medical Officer	$331,151			Mixed	31 Jul 2025
William Michael Brown	Chief Financial Officer	$199,361			Mixed	31 Jul 2021
Jerome Benedict Durso	President and CEO, Director	$149,150	+$169,459	+114%	Filing P/S	01 Apr 2026
Gregory L. Weaver	Chief Financial Officer	$119,941	+$49,199	+70%	Filing P/S	01 Apr 2026
John Gill	Director	$73,944	+$82,600	+112%	Filing P/S	01 May 2026
Andrew Shutterly	Acting Chief Financial Officer	$61,523			Mixed	31 Jul 2024
Wayne Pisano	Director	$55,098	+$20,410	+59%	Filing P/S	01 May 2026
Catherine A. Sohn	Director	$6,352	+$2,118	+50%	Filing P/S	01 May 2026
Diane Jorkasky	Director	$2,002	+$2,003	+100%	Filing P/S	01 May 2026
Klaus Schafer	Director				Mixed	01 May 2026
Linda M. Richardson	Chief Commercial Officer				Mixed	16 Sep 2025
Christophe Arbet-Engels	Chief Medical Officer				Mixed	01 Oct 2025
Mitchel Sayare	Director				Mixed	01 May 2026
Philip Hodges	Director				Mixed	01 May 2026
Teri L. Lawver	Director				Mixed	01 May 2026

Recent insider transactions for Altimmune, Inc.

Showing up to 300 recent insider transactions from the last 12 months.

Insider	Symbol	Class	Transaction	%	SEC-reported value	SEC-reported price	Shares	Shares owned	Date	Ownership
Teri L. Lawver	ALT	Stock Options (option to buy)	Award				48,800	48,800	01 May 2026	Direct
Catherine A. Sohn	ALT	Stock Options (option to buy)	Award				48,800	48,800	01 May 2026	Direct
Diane Jorkasky	ALT	Stock Options (option to buy)	Award				48,800	48,800	01 May 2026	Direct
Klaus Schafer	ALT	Stock Options (option to buy)	Award				48,800	48,800	01 May 2026	Direct
Wayne Pisano	ALT	Stock Options (option to buy)	Award				48,800	48,800	01 May 2026	Direct
Philip Hodges	ALT	Stock Options (option to buy)	Award				48,800	48,800	01 May 2026	Direct
John Gill	ALT	Stock Options (option to buy)	Award				48,800	48,800	01 May 2026	Direct
Mitchel Sayare	ALT	Stock Options (option to buy)	Award				48,800	48,800	01 May 2026	Direct
John Gill	ALT	Common Stock, par value $0.0001	Purchase	73.6%	$31,350	$3.41	9,200	21,700	06 Apr 2026	Direct
Gregory L. Weaver	ALT	Common Stock, par value $0.0001	Purchase	35.6%	$31,499	$3.15	10,000	38,078	01 Apr 2026	Direct
Jerome Benedict Durso	ALT	Common Stock, par value $0.0001	Purchase	46.2%	$47,100	$3.14	15,000	47,500	01 Apr 2026	Direct
Gregory L. Weaver	ALT	Common Stock, par value $0.0001	Purchase	21.7%	$17,700	$3.54	5,000	28,078	06 Mar 2026	Direct
Jerome Benedict Durso	ALT	Common Stock, par value $0.0001	Purchase	160%	$70,790	$3.54	20,000	32,500	06 Mar 2026	Direct
M. Scot Roberts	ALT	Restricted Stock Units	Award				95,430	95,430	26 Feb 2026	Direct
M. Scot Roberts	ALT	Stock Options (option to buy)	Award				222,670	222,670	26 Feb 2026	Direct
Gregory L. Weaver	ALT	Restricted Stock Units	Award				111,000	111,000	26 Feb 2026	Direct
Gregory L. Weaver	ALT	Stock Options (option to buy)	Award				259,000	259,000	26 Feb 2026	Direct
M. Scot Roberts	ALT	Common Stock, par value $0.0001	Tax liability	-2.02%			-2,329	112,824	02 Feb 2026	Direct
M. Scot Roberts	ALT	Common Stock, par value $0.0001	Options Exercise	7.24%			7,775	115,153	02 Feb 2026	Direct
M. Scot Roberts	ALT	Restricted Stock Units	Options Exercise	-100%			-7,775	0	02 Feb 2026	Direct
M. Scot Roberts	ALT	Common Stock, par value $0.0001	Award	5.47%			5,567	107,378	31 Jan 2026	Direct
Raymond M. Jordt	ALT	Common Stock, par value $0.0001	Award	6.97%			4,571	70,107	31 Jan 2026	Direct
Vipin K. Garg	ALT	Common Stock, par value $0.0001	Award	1.66%			6,926	424,519	31 Jan 2026	Direct
M. Scot Roberts	ALT	Common Stock, par value $0.0001	Tax liability	-2.73%			-2,859	101,811	30 Jan 2026	Direct
M. Scot Roberts	ALT	Common Stock, par value $0.0001	Options Exercise	9.72%			9,275	104,670	30 Jan 2026	Direct
M. Scot Roberts	ALT	Restricted Stock Units	Options Exercise	-50%			-9,275	9,275	30 Jan 2026	Direct
Vipin K. Garg	ALT	Common Stock, par value $0.0001	Tax liability	-2.71%			-11,632	417,593	30 Jan 2026	Direct
Vipin K. Garg	ALT	Common Stock, par value $0.0001	Options Exercise	6.65%			26,775	429,225	30 Jan 2026	Direct
Vipin K. Garg	ALT	Restricted Stock Units	Options Exercise	-50%			-26,775	26,775	30 Jan 2026	Direct
Raymond M. Jordt	ALT	Common Stock, par value $0.0001	Tax liability	-6.06%			-4,229	65,536	27 Jan 2026	Direct
Raymond M. Jordt	ALT	Common Stock, par value $0.0001	Options Exercise	29.4%			15,850	69,765	27 Jan 2026	Direct
Raymond M. Jordt	ALT	Restricted Stock Units	Options Exercise	-25%			-15,850	47,550	27 Jan 2026	Direct
M. Scot Roberts	ALT	Common Stock, par value $0.0001	Tax liability	-4.74%			-4,748	95,395	27 Jan 2026	Direct
M. Scot Roberts	ALT	Common Stock, par value $0.0001	Options Exercise	18.8%			15,850	100,143	27 Jan 2026	Direct
M. Scot Roberts	ALT	Restricted Stock Units	Options Exercise	-25%			-15,850	47,550	27 Jan 2026	Direct
Vipin K. Garg	ALT	Common Stock, par value $0.0001	Tax liability	-4.26%			-17,898	402,450	27 Jan 2026	Direct
Vipin K. Garg	ALT	Common Stock, par value $0.0001	Options Exercise	10.9%			41,200	420,348	27 Jan 2026	Direct
Vipin K. Garg	ALT	Restricted Stock Units	Options Exercise	-25%			-41,200	123,600	27 Jan 2026	Direct
Raymond M. Jordt	ALT	Common Stock, par value $0.0001	Tax liability	-6.67%			-3,855	53,915	25 Jan 2026	Direct
Raymond M. Jordt	ALT	Common Stock, par value $0.0001	Options Exercise	33.8%			14,600	57,770	25 Jan 2026	Direct
Raymond M. Jordt	ALT	Restricted Stock Units	Options Exercise	-33.3%			-14,600	29,200	25 Jan 2026	Direct
M. Scot Roberts	ALT	Common Stock, par value $0.0001	Tax liability	-4.93%			-4,373	84,293	25 Jan 2026	Direct
M. Scot Roberts	ALT	Common Stock, par value $0.0001	Options Exercise	19.7%			14,600	88,666	25 Jan 2026	Direct
M. Scot Roberts	ALT	Restricted Stock Units	Options Exercise	-33.3%			-14,600	29,200	25 Jan 2026	Direct
Vipin K. Garg	ALT	Common Stock, par value $0.0001	Tax liability	-4.53%			-17,984	379,148	25 Jan 2026	Direct
Vipin K. Garg	ALT	Common Stock, par value $0.0001	Options Exercise	11.8%			42,050	397,132	25 Jan 2026	Direct
Vipin K. Garg	ALT	Restricted Stock Units	Options Exercise	-33.3%			-42,050	84,100	25 Jan 2026	Direct
Wayne Pisano	ALT	Common Stock, par value $0.0001	Purchase	58.8%	$20,410	$4.08	5,000	13,498	08 Jan 2026	Direct
Catherine A. Sohn	ALT	Common Stock, par value $0.0001	Purchase	50%	$2,118	$4.24	500	1,500	05 Jan 2026	Direct
Raymond M. Jordt	ALT	Common Stock, par value $0.0001	Tax liability	-5.42%			-2,475	43,170	01 Jan 2026	Direct

^* marks a reported price that did not pass the local price check.