Altimmune, Inc. Schedule 13G/A reports that Tang Capital Management, LLC and related entities and persons beneficially own 666,022 shares of common stock, representing 0.3% of the class. The filing states the percent is calculated from 194,199,358 shares outstanding as of April 24, 2026 as shown in a prospectus filed on April 24, 2026. The filing lists shared voting and dispositive power among Tang Capital Management, LLC, Tang Capital Partners International, LP, and Kevin Tang, and affirms the position falls within the "Ownership of 5 Percent or Less of a Class" category.
Positive
None.
Negative
None.
Insights
Minor passive stake filed via Schedule 13G/A; shared control noted.
The filing shows a 666,022-share holding, equal to 0.3% of common stock based on 194,199,358 shares outstanding as of April 24, 2026. Ownership is reported as shared voting and dispositive power among TCM, TCPI, and Kevin Tang.
Because the position is under 5%, it is reported on a passive/beneficial basis under the Schedule 13G/A framework. Subsequent filings would disclose any material change in stake or control.
Key Figures
Beneficially owned shares:666,022 sharesPercent of class:0.3%Shares outstanding used:194,199,358 shares
3 metrics
Beneficially owned shares666,022 sharesAmount beneficially owned reported in Schedule 13G/A
Percent of class0.3%Percent of common stock based on outstanding shares
Shares outstanding used194,199,358 sharesOutstanding shares as of April 24, 2026 (prospectus basis)
Key Terms
Schedule 13G/A, beneficially own, shared voting and dispositive power
3 terms
Schedule 13G/Aregulatory
"This Statement on (this "Statement") is filed by TCM"
A Schedule 13G/A is an amended public filing with the U.S. securities regulator that updates a previous Schedule 13G, disclosing when an individual or group holds a substantial (typically over 5%) stake in a company and is claiming a passive, non‑controlling intent. Investors monitor these updates because rising or falling holdings can signal changing confidence, potential future moves, or shifts in voting power — like watching a public ledger where large shareholders quietly adjust their positions.
Beneficially own means having the economic rights and risks of a security—such as the right to receive dividends, sell the shares, or profit from price changes—whether or not your name appears on the official share register. Think of it like renting a car: you use it and reap the benefits even if the title lists someone else. Investors care because beneficial ownership determines who truly controls value, must be disclosed under securities rules, and can signal potential influence or trading activity that affects a stock’s price.
shared voting and dispositive powerregulatory
"shares voting and dispositive power over such shares with Tang Capital Partners International, LP"
What stake does Tang Capital Management report in ALT?
Tang Capital Management and related persons report 666,022 shares, representing 0.3% of Altimmune's common stock based on 194,199,358 shares outstanding as of April 24, 2026.
Who shares voting and dispositive power over the reported ALT shares?
The filing states shared voting and dispositive power is held by Tang Capital Management, LLC, Tang Capital Partners International, LP, and Kevin Tang over the 666,022 shares.
Is the reported ALT position greater than 5%?
No. The filing classifies the holding under "Ownership of 5 Percent or Less of a Class," reporting a 0.3% ownership stake of common stock.
What outstanding-share figure does the filing use to calculate the percentage?
The percentage is calculated using 194,199,358 shares outstanding as of April 24, 2026, cited from a prospectus filed on April 24, 2026.
Which entities and addresses are listed for the filers in the Schedule 13G/A?
Addresses listed: 4747 Executive Drive, Suite 210, San Diego, CA 92121 for TCM, Kevin Tang, TCP and TCPI; 400 S. 4th Street, 3rd Floor, Las Vegas, NV 89101 for TCP III and TCP IV.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 3)
Altimmune, Inc.
(Name of Issuer)
Common stock, par value $0.0001 per share
(Title of Class of Securities)
02155H200
(CUSIP Number)
03/31/2026
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
Rule 13d-1(b)
Rule 13d-1(c)
Rule 13d-1(d)
schemaVersion:
SCHEDULE 13G
CUSIP Number(s):
02155H200
1
Names of Reporting Persons
TANG CAPITAL MANAGEMENT, LLC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
666,022.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
666,022.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
666,022.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0.3 %
12
Type of Reporting Person (See Instructions)
OO
Comment for Type of Reporting Person: Tang Capital Management, LLC ("TCM") shares voting and dispositive power over such shares with Tang Capital Partners International, LP ("TCPI") and Kevin Tang. The percentages used herein are based on 194,199,358 shares of Common Stock outstanding as of April 24, 2026, as set forth in the Prospectus filed on Form 424B5 that was filed with the Securities and Exchange Commission on April 24, 2026.
SCHEDULE 13G
CUSIP Number(s):
02155H200
1
Names of Reporting Persons
KEVIN TANG
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
UNITED STATES
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
666,022.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
666,022.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
666,022.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0.3 %
12
Type of Reporting Person (See Instructions)
IN
Comment for Type of Reporting Person: Kevin Tang shares voting and dispositive power over such shares with TCPI and TCM.
SCHEDULE 13G
CUSIP Number(s):
02155H200
1
Names of Reporting Persons
TANG CAPITAL PARTNERS, LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
0.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
0.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
0.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0 %
12
Type of Reporting Person (See Instructions)
PN
SCHEDULE 13G
CUSIP Number(s):
02155H200
1
Names of Reporting Persons
TANG CAPITAL PARTNERS INTERNATIONAL, LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
666,022.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
666,022.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
666,022.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0.3 %
12
Type of Reporting Person (See Instructions)
PN
Comment for Type of Reporting Person: TCPI shares voting and dispositive power over such shares with TCM and Kevin Tang.
SCHEDULE 13G
CUSIP Number(s):
02155H200
1
Names of Reporting Persons
TANG CAPITAL PARTNERS III, INC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
NEVADA
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
0.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
0.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
0.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0.0 %
12
Type of Reporting Person (See Instructions)
CO
SCHEDULE 13G
CUSIP Number(s):
02155H200
1
Names of Reporting Persons
TANG CAPITAL PARTNERS IV, INC
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
NEVADA
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
0.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
0.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
0.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
0.0 %
12
Type of Reporting Person (See Instructions)
CO
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Altimmune, Inc.
(b)
Address of issuer's principal executive offices:
910 Clopper Road, Suite 201S, Gaithersburg, MD, 20878
Item 2.
(a)
Name of person filing:
This Statement on Schedule 13G (this "Statement") is filed by TCM, the general partner of Tang Capital Partners, LP ("TCP") and TCPI; Kevin Tang, the manager of TCM and Chief Executive Officer of Tang Capital Partners III, Inc. ("TCP III") and Tang Capital Partners IV, Inc. ("TCP IV"); TCP; TCPI; TCP III; and TCP IV.
(b)
Address or principal business office or, if none, residence:
The address of TCM, Kevin Tang, TCP and TCPI is 4747 Executive Drive, Suite 210, San Diego, CA 92121. The address of TCP III and TCP IV is 400 S. 4th Street, 3rd Floor, Las Vegas, NV 89101.
(c)
Citizenship:
TCM is a Delaware limited liability company. Mr. Tang is a United States citizen. TCP and TCPI are Delaware limited partnerships. TCP III and TCP IV are Nevada corporations that are indirectly wholly owned by TCP.
(d)
Title of class of securities:
Common stock, par value $0.0001 per share
(e)
CUSIP No.:
02155H200
Item 3.
If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)
An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)
An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)
A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)
A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)
A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
(k)
Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.
Ownership
(a)
Amount beneficially owned:
666,022
(b)
Percent of class:
0.3 %
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
0 shares
(ii) Shared power to vote or to direct the vote:
666,022 shares
(iii) Sole power to dispose or to direct the disposition of:
0 shares
(iv) Shared power to dispose or to direct the disposition of:
666,022 shares
Item 5.
Ownership of 5 Percent or Less of a Class.
Ownership of 5 percent or less of a class
Item 6.
Ownership of more than 5 Percent on Behalf of Another Person.
Not Applicable
Item 7.
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
Not Applicable
Item 8.
Identification and Classification of Members of the Group.
Not Applicable
Item 9.
Notice of Dissolution of Group.
Not Applicable
Item 10.
Certifications:
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
TANG CAPITAL MANAGEMENT, LLC
Signature:
/s/ Kevin Tang
Name/Title:
Manager
Date:
05/15/2026
KEVIN TANG
Signature:
/s/ Kevin Tang
Name/Title:
Self
Date:
05/15/2026
TANG CAPITAL PARTNERS, LP
Signature:
/s/ Kevin Tang
Name/Title:
Manager, Tang Capital Management, LLC, General Partner
Date:
05/15/2026
TANG CAPITAL PARTNERS INTERNATIONAL, LP
Signature:
/s/ Kevin Tang
Name/Title:
Manager, Tang Capital Management, LLC, General Partner
