Theriva Biologics (TOVX) reported a new Schedule 13G indicating that the Jeffrey Matthew Gryga Irrevocable Trust beneficially owns 739,211 shares of common stock, representing 7.7% of the class as of the event date 10/24/2025.
The trust has sole voting and dispositive power over these 739,211 shares. Jeffrey Matthew Gryga, as sole trustee, reports shared voting and dispositive power over the same shares through the trust. The filing includes a certification that the securities were not acquired for the purpose of changing or influencing control of the issuer.
Positive
None.
Negative
None.
FAQ
What did the Schedule 13G disclose for TOVX?
The Jeffrey Matthew Gryga Irrevocable Trust reported beneficial ownership of 739,211 TOVX common shares, equal to 7.7% of the class.
Who filed the Schedule 13G related to TOVX?
Jeffrey Matthew Gryga Irrevocable Trust and Jeffrey Matthew Gryga (sole trustee) filed jointly.
What voting and dispositive powers were reported?
The trust has sole voting and dispositive power over 739,211 shares; Jeffrey Matthew Gryga reports shared power over the same shares as trustee.
What is the reported percentage ownership of TOVX?
The filing states a 7.7% beneficial ownership of the common stock class.
What is the event date for this ownership report?
The date of the event requiring the filing is 10/24/2025.
Did the filer indicate an intent to influence control of TOVX?
No. The certification states the securities were not acquired for the purpose of changing or influencing control.
Is this filing made as part of a group?
The filing does not identify a group and is presented by the trust and trustee together under a joint filing agreement.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
Theriva Biologics, Inc.
(Name of Issuer)
Common stock
(Title of Class of Securities)
87164U508
(CUSIP Number)
10/24/2025
(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)
SCHEDULE 13G
CUSIP No.
87164U508
1
Names of Reporting Persons
Jeffrey Matthew Gryga Irrevocable Trust
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
739,211.00
6
Shared Voting Power
0.00
7
Sole Dispositive Power
739,211.00
8
Shared Dispositive Power
0.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
739,211.00
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)
7.7 %
12
Type of Reporting Person (See Instructions)
OO
SCHEDULE 13G
CUSIP No.
87164U508
1
Names of Reporting Persons
Gryga Jeffrey Matthew
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
739,211.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
739,211.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
739,211.00
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)
7.7 %
12
Type of Reporting Person (See Instructions)
IN
Comment for Type of Reporting Person: Jeffrey Matthew Gryga is the sole Trustee of the Jeffrey Matthew Gryga Irrevocable Trust.
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Theriva Biologics, Inc.
(b)
Address of issuer's principal executive offices:
9605 MEDICAL CENTER DRIVE, SUITE 270, ROCKVILLE, MARYLAND, 20850
Item 2.
(a)
Name of person filing:
1) Jeffrey Matthew Gryga Irrevocable Trust
2) Jeffrey Matthew Gryga. Jeffrey Matthew Gryga is the sole Trustee of the Jeffrey Matthew Gryga Irrevocable Trust.
(b)
Address or principal business office or, if none, residence:
1) Jeffrey Matthew Gryga Irrevocable Trust:
528 W. 4th Ave
North Pole, AK 99705
2) Jeffrey Matthew Gryga:
528 W. 4th Ave
North Pole, AK 99705
(c)
Citizenship:
1) Jeffrey Matthew Gryga Irrevocable Trust:
United States
2) Jeffrey Matthew Gryga:
United States
(d)
Title of class of securities:
Common stock
(e)
CUSIP No.:
87164U508
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:
1) Jeffrey Matthew Gryga Irrevocable Trust owns 739,211 shares and has sole power to vote and/or dispose of the shares.
2) Jeffrey Matthew Gryga is the sole Trustee of the Jeffrey Matthew Gryga Irrevocable Trust and has shared power to vote and/or dispose of the 739,211 shares owned by the Jeffrey Matthew Gryga Irrevocable Trust.
(b)
Percent of class:
7.7%
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
1) Jeffrey Matthew Gryga Irrevocable Trust owns 739,211 shares and has sole power to vote and/or dispose of the shares.
2) Jeffrey Matthew Gryga is the sole Trustee of the Jeffrey Matthew Gryga Irrevocable Trust and has shared power to vote and/or dispose of the 739,211 shares owned by the Jeffrey Matthew Gryga Irrevocable Trust.
(ii) Shared power to vote or to direct the vote:
1) Jeffrey Matthew Gryga Irrevocable Trust owns 739,211 shares and has no shared power to vote and/or dispose of the shares.
2) Jeffrey Matthew Gryga is the sole Trustee of the Jeffrey Matthew Gryga Irrevocable Trust and has shared power to vote and/or dispose of the 739,211 shares owned by the Jeffrey Matthew Gryga Irrevocable Trust.
(iii) Sole power to dispose or to direct the disposition of:
1) Jeffrey Matthew Gryga Irrevocable Trust owns 739,211 shares and has sole power to vote and/or dispose of the shares.
2) Jeffrey Matthew Gryga is the sole Trustee of the Jeffrey Matthew Gryga Irrevocable Trust and has shared power to vote and/or dispose of the 739,211 shares owned by the Jeffrey Matthew Gryga Irrevocable Trust.
(iv) Shared power to dispose or to direct the disposition of:
1) Jeffrey Matthew Gryga Irrevocable Trust owns 739,211 shares and has no shared power to vote and/or dispose of the shares.
2) Jeffrey Matthew Gryga is the sole Trustee of the Jeffrey Matthew Gryga Irrevocable Trust and has shared power to vote and/or dispose of the 739,211 shares owned by the Jeffrey Matthew Gryga Irrevocable Trust.
Item 5.
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.
Jeffrey Matthew Gryga Irrevocable Trust
Signature:
Jeffrey Matthew Gryga
Name/Title:
Jeffrey Matthew Gryga, Trustee of Jeffrey Matthew Gryga Irrevocable Trust
