THERAPEUTICS, INC. reports that Nantahala Capital Management, LLC and two affiliated reporting persons together beneficially own 3,050,040 shares of Common Stock.
As of March 31, 2026 the filing states those shares represent 4.58% of the class. The filing lists shared voting and dispositive power over the 3,050,040 shares and notes Messrs. Wilmot B. Harkey and Daniel Mack are filing as control persons in respect of shares held by Nantahala. Signatures are dated May 15, 2026.
Positive
None.
Negative
None.
Insights
Minor passive stake disclosed: 3,050,040 shares, 4.58% as of March 31, 2026.
The filing documents an aggregate 4.58% beneficial position held by Nantahala-managed accounts and attributes shared voting and dispositive power to Nantahala and its managing members. This is a passive disclosure under Schedule 13G/A rather than an active Schedule 13D acquisition narrative.
Future filings may show changes; any material increase above 5% or a switch to Schedule 13D would be a notable shift in intent. Timing for such changes is not included in the provided excerpt.
Key Figures
Shares beneficially owned:3,050,040 sharesPercent of class:4.58%CUSIP:359616109+2 more
5 metrics
Shares beneficially owned3,050,040 sharesAs of March 31, 2026
Percent of class4.58%As of March 31, 2026
CUSIP359616109Common stock, par value $0.001 per share
Shared voting power3,050,040 sharesReported shared voting power for Nantahala, Harkey, Mack
Shared dispositive power3,050,040 sharesReported shared dispositive power for Nantahala, Harkey, Mack
Key Terms
Schedule 13G/A, Beneficial owner, Shared dispositive power, Control person
4 terms
Schedule 13G/Aregulatory
"As of March 31, 2026, Nantahala may be deemed to be the beneficial owner"
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.
Beneficial ownerregulatory
"Nantahala may be deemed to be the beneficial owner of 3,050,040 Shares"
A beneficial owner is the person who ultimately owns or controls a financial asset or property, even if their name isn't directly on official documents. Think of it like someone who secretly holds the keys to a safe deposit box—others may appear to have access, but the true owner is the one who benefits from what's inside. Identifying beneficial owners helps ensure transparency and prevent illegal activities like money laundering or fraud.
Shared dispositive powerregulatory
"Shared Dispositive Power 3,050,040.00"
Control personregulatory
"each of Messrs. Harkey and Mack is filing this as a control person"
A control person is an individual or entity that can significantly influence a company’s decisions and direction through ownership, voting power, or contractual rights—think of them as the captain who can steer the ship. Investors care because a control person’s choices affect corporate strategy, board appointments, and transactions that can raise or lower a stock’s value, and they often carry additional legal responsibilities and disclosure requirements to protect other shareholders.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 1)
FULCRUM THERAPEUTICS, INC.
(Name of Issuer)
Common stock, par value $0.001 per share
(Title of Class of Securities)
359616109
(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):
359616109
1
Names of Reporting Persons
Nantahala 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
MASSACHUSETTS
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
3,050,040.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
3,050,040.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
3,050,040.00
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)
4.58 %
12
Type of Reporting Person (See Instructions)
IA
SCHEDULE 13G
CUSIP Number(s):
359616109
1
Names of Reporting Persons
Wilmot B. Harkey
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
3,050,040.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
3,050,040.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
3,050,040.00
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)
4.58 %
12
Type of Reporting Person (See Instructions)
HC
SCHEDULE 13G
CUSIP Number(s):
359616109
1
Names of Reporting Persons
Daniel Mack
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
3,050,040.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
3,050,040.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
3,050,040.00
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)
4.58 %
12
Type of Reporting Person (See Instructions)
HC
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
FULCRUM THERAPEUTICS, INC.
(b)
Address of issuer's principal executive offices:
26 LANDSDOWNE STREET CAMBRIDGE, MASSACHUSETTS, 02139
Item 2.
(a)
Name of person filing:
(1) Nantahala Capital Management, LLC ("Nantahala")
(2) Wilmot B. Harkey
(3) Daniel Mack (together the "Reporting Persons")
(b)
Address or principal business office or, if none, residence:
130 Main St. 2nd Floor, New Canaan, Connecticut 06840
(c)
Citizenship:
(1) Nantahala is a Massachusetts limited liability company.
(2) Each of Messrs. Harkey and Mack is a citizen of the United States of America.
(d)
Title of class of securities:
Common stock, par value $0.001 per share
(e)
CUSIP No.:
359616109
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:
As of March 31, 2026, Nantahala may be deemed to be the beneficial owner of 3,050,040 Shares held by funds and separately managed accounts under its control, and as the managing members of Nantahala, each of Messrs. Harkey and Mack may be deemed to be a beneficial owner of those Shares.
(b)
Percent of class:
As of March 31, 2026, each of the Reporting Persons may be deemed to be the beneficial owner of the following percentage of the total number of Shares outstanding:
(1) Nantahala Capital Management, LLC ("Nantahala") : 4.58%
(2) Wilmot B. Harkey: 4.58%
(3) Daniel Mack: 4.58%
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
(1) Nantahala Capital Management, LLC ("Nantahala") : 0 Shares.
(2) Wilmot B. Harkey: 0 Shares.
(3) Daniel Mack: 0 Shares.
(ii) Shared power to vote or to direct the vote:
(1) Nantahala Capital Management, LLC ("Nantahala") : 3,050,040 Shares.
(2) Wilmot B. Harkey: 3,050,040 Shares.
(3) Daniel Mack: 3,050,040 Shares.
(iii) Sole power to dispose or to direct the disposition of:
(1) Nantahala Capital Management, LLC ("Nantahala") : 0 Shares.
(2) Wilmot B. Harkey: 0 Shares.
(3) Daniel Mack: 0 Shares.
(iv) Shared power to dispose or to direct the disposition of:
(1) Nantahala Capital Management, LLC ("Nantahala") : 3,050,040 Shares.
(2) Wilmot B. Harkey: 3,050,040 Shares.
(3) Daniel Mack: 3,050,040 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.
If a parent holding company has filed this schedule, pursuant to Rule 13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary.
Each of Messrs. Harkey and Mack is filing this Schedule 13G as a control person in respect of shares beneficially owned by Nantahala, an investment adviser as described in ss. 240.13d-1(b)(1)(ii)(E). See Item 4(a).
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 acquired and are held in the ordinary course of business and 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.
