Karyopharm Therapeutics Inc. is the issuer named in an amended Schedule 13G reporting beneficial ownership of its common stock by Acorn Bioventures, L.P., Acorn Bioventures 2, L.P. and Anders Hove. Acorn Bioventures, L.P. reported 539,373 shares (2.4%), and Acorn Bioventures 2, L.P. reported 744,848 shares (3.3%). Each partnership’s general partner reported the same corresponding amount.
Anders Hove, manager of both general partners, reported shared voting and dispositive power over 1,284,221 shares (5.7%). The reported ownership percentages are based on 22,681,460 shares outstanding as of June 30, 2026.
Acorn Bioventures, L.P. beneficial ownership539,373 shares (2.4%)Reported with shared voting and dispositive power
Acorn Bioventures 2, L.P. beneficial ownership744,848 shares (3.3%)Reported with shared voting and dispositive power
Anders Hove beneficial ownership1,284,221 shares (5.7%)Reported with shared voting and dispositive power
Common shares outstanding22,681,460 sharesAs of June 30, 2026; basis for the reported percentages
Key Terms
beneficially own, Shared Voting Power, Shared Dispositive Power
3 terms
beneficially ownfinancial
"may be deemed to beneficially own the shares"
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 Powerfinancial
"Shared Voting Power 539,373.00"
Shared voting power occurs when two or more parties jointly have the right to vote or decide how a block of company shares is cast, like co-owners who must agree before moving a piece of furniture. Investors care because who controls voting rights affects board elections, major corporate decisions and takeover outcomes, and shared control can alter regulatory disclosures and the practical influence any holder has over a company’s direction and value.
Shared Dispositive Powerfinancial
"Shared Dispositive Power 539,373.00"
FAQ
AI-generated questions and answers. How Rhea-AI works. Not financial advice.
How many KPTI shares did Anders Hove report beneficially owning?
Anders Hove reported beneficial ownership of 1,284,221 Karyopharm common shares, or 5.7%, with shared voting and shared dispositive power. The filing identifies him as manager of each of Acorn Capital Advisors GP, LLC and Acorn Capital Advisors GP 2, LLC.
What share count underlies KPTI's reported ownership percentages?
The reported percentages are based on 22,681,460 shares outstanding as of June 30, 2026.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 1)
Karyopharm Therapeutics Inc.
(Name of Issuer)
Common Stock, $0.0001 Par Value
(Title of Class of Securities)
48576U205
(CUSIP Number)
09/22/2026
(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):
48576U205
1
Names of Reporting Persons
ACORN BIOVENTURES, L.P.
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
539,373.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
539,373.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
539,373.00
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)
2.4 %
12
Type of Reporting Person (See Instructions)
PN
SCHEDULE 13G
CUSIP Number(s):
48576U205
1
Names of Reporting Persons
ACORN CAPITAL ADVISORS GP, 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
539,373.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
539,373.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
539,373.00
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)
2.4 %
12
Type of Reporting Person (See Instructions)
OO
SCHEDULE 13G
CUSIP Number(s):
48576U205
1
Names of Reporting Persons
ACORN BIOVENTURES 2, L.P.
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
744,848.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
744,848.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
744,848.00
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)
3.3 %
12
Type of Reporting Person (See Instructions)
PN
SCHEDULE 13G
CUSIP Number(s):
48576U205
1
Names of Reporting Persons
Acorn Capital Advisors GP 2, 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
744,848.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
744,848.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
744,848.00
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)
3.3 %
12
Type of Reporting Person (See Instructions)
OO
SCHEDULE 13G
CUSIP Number(s):
48576U205
1
Names of Reporting Persons
Anders Hove
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
1,284,221.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
1,284,221.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
1,284,221.00
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)
5.7 %
12
Type of Reporting Person (See Instructions)
IN
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Karyopharm Therapeutics Inc.
(b)
Address of issuer's principal executive offices:
85 WELLS AVENUE, NEWTON, MASSACHUSETTS, 02459.
Item 2.
(a)
Name of person filing:
Acorn Bioventures, L.P.
Acorn Capital Advisors GP, LLC
Acorn Bioventures 2, L.P.
Acorn Capital Advisors GP2, LLC
Anders Hove
(b)
Address or principal business office or, if none, residence:
420 Lexington Avenue, Suite 2626, New York, New York 10170
(c)
Citizenship:
Acorn Bioventures, L.P. and Acorn Bioventures 2 L.P. are both Delaware limited partnerships. Acorn Capital Advisors GP, LLC and Acorn Capital Advisors GP 2, LLC are both Delaware limited liability companies. Anders Hove is a citizen of the United States of America.
(d)
Title of class of securities:
Common Stock, $0.0001 Par Value
(e)
CUSIP No.:
48576U205
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:
The information required by Items 4(a) - (c) is set forth in Rows (5) - (11) of the cover page for each Reporting Person hereto and is incorporated herein by reference for each Reporting Person.
(b)
Percent of class:
The percentages set forth herein are calculated based upon 22,681,460 shares of Common Stock outstanding as of June 30, 2026 as reported in the Issuer's Quarterly Report on Form 10-Q for the quarterly period ended June 30, 2026 filed with the Securities and Exchange Commission on August 13, 2026.
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
Acorn Capital Advisors GP, LLC is the General Partner of Acorn Bioventures, L.P. and may be deemed to beneficially own the shares of Common Stock beneficially owned by Acorn Bioventures, L.P. Acorn Capital Advisors GP 2, LLC is the General Partner of Acorn Bioventures 2, L.P. and may be deemed to beneficially own the shares of Common Stock beneficially owned by Acorn Bioventures 2, L.P.
(ii) Shared power to vote or to direct the vote:
Anders Hove, in his capacity as Manager of each of Acorn Capital Advisors GP, LLC and Acorn Capital Advisors GP 2, LLC, may be deemed to beneficially own the shares beneficially owned by each of Acorn Capital Advisors GP, LLC and Acorn Capital Advisors GP 2, LLC.
(iii) Sole power to dispose or to direct the disposition of:
NA
(iv) Shared power to dispose or to direct the disposition of:
NA
Item 5.
Ownership of 5 Percent or Less of a Class.
Not Applicable
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.