Tango Therapeutics, Inc. (TNGX) received an amended Schedule 13G/A showing that EcoR1 Capital, LLC, EcoR1 Capital Fund Qualified, L.P., and Oleg Nodelman now report zero beneficial ownership of the company’s common stock. As of December 31, 2025, each reporting person lists 0 shares beneficially owned and a 0% stake, with no sole or shared voting or dispositive power. The filing confirms they own 5 percent or less of the class. The parties also state they are filing jointly but expressly disclaim being part of a group and disclaim beneficial ownership beyond any pecuniary interest.
Positive
None.
Negative
None.
Insights
EcoR1 and affiliates report 0% ownership in Tango Therapeutics common stock as of December 31, 2025.
The filing shows EcoR1 Capital, LLC, EcoR1 Capital Fund Qualified, L.P., and Oleg Nodelman each reporting 0 shares of Tango Therapeutics common stock beneficially owned, corresponding to 0% of the class. They also report no sole or shared voting or dispositive power.
The statement notes ownership of 5 percent or less of the class, indicating they no longer meet the threshold for significant holder reporting. The parties file jointly but expressly disclaim group status and beneficial ownership beyond any pecuniary interest. Subsequent filings may clarify any future changes in ownership.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 3)
Tango Therapeutics, Inc.
(Name of Issuer)
Common Stock
(Title of Class of Securities)
87583X109
(CUSIP Number)
12/31/2025
(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.
87583X109
1
Names of Reporting Persons
EcoR1 Capital, 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
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)
IA, OO
SCHEDULE 13G
CUSIP No.
87583X109
1
Names of Reporting Persons
Oleg Nodelman
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
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)
HC, IN
SCHEDULE 13G
CUSIP No.
87583X109
1
Names of Reporting Persons
EcoR1 Capital Fund Qualified, 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
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
Item 1.
(a)
Name of issuer:
Tango Therapeutics, Inc.
(b)
Address of issuer's principal executive offices:
201 Brookline Ave., Suite 901, Boston, MA 02215
Item 2.
(a)
Name of person filing:
EcoR1 Capital, LLC, a Delaware limited liability company ("EcoR1")
EcoR1 Capital Fund Qualified, L.P., a Delaware limited partnership ("Qualified Fund")
Oleg Nodelman
Qualified Fund is filing this statement jointly with the other reporting persons, but not as a member of a group, and it expressly disclaims membership in a group. In addition, the filing of this Schedule 13G on behalf of Qualified Fund should not be construed as an admission that it is, and it disclaims that it is, a beneficial owner, as defined in Rule 13d-3 under the Act, of any securities covered by this Schedule 13G. Each reporting person also disclaims beneficial ownership of the securities reported herein except to the extent of that person's pecuniary interest therein.
(b)
Address or principal business office or, if none, residence:
357 Tehama Street #3
San Francisco, CA 94103
(c)
Citizenship:
See Item 4 of the cover sheet for each reporting person.
(d)
Title of class of securities:
Common Stock
(e)
CUSIP No.:
87583X109
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:
EcoR1: 0
Qualified Fund: 0
Oleg Nodelman: 0
(b)
Percent of class:
EcoR1: 0%
Qualified Fund: 0%
Oleg Nodelman: 0%
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
EcoR1: 0
Qualified Fund: 0
Oleg Nodelman: 0
(ii) Shared power to vote or to direct the vote:
EcoR1: 0
Qualified Fund: 0
Oleg Nodelman: 0
(iii) Sole power to dispose or to direct the disposition of:
EcoR1: 0
Qualified Fund: 0
Oleg Nodelman: 0
(iv) Shared power to dispose or to direct the disposition of:
EcoR1: 0
Qualified Fund: 0
Oleg Nodelman: 0
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.
If a group has filed this schedule pursuant to §240.13d-1(b)(1)(ii)(J), so indicate under Item 3(j) and attach an exhibit stating the identity and Item 3 classification of each member of the group. If a group has filed this schedule pursuant to §240.13d-1(c) or §240.13d-1(d), attach an exhibit stating the identity of each member of the group.
EcoR1 is the general partner and investment adviser of investment funds, including Qualified Fund. Mr. Nodelman is the control person of EcoR1.
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.
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.
EcoR1 Capital, LLC
Signature:
/s/ Oleg Nodelman
Name/Title:
Manager
Date:
02/13/2026
Oleg Nodelman
Signature:
/s/ Oleg Nodelman
Name/Title:
Reporting person
Date:
02/13/2026
EcoR1 Capital Fund Qualified, L.P.
Signature:
/s/ Oleg Nodelman
Name/Title:
Manager of the General Partner, EcoR1 Capital, LLC
Date:
02/13/2026
Exhibit Information
Exhibit 99.1 - Agreement Regarding Joint Filing of Statement on Schedule 13D or 13G
What does EcoR1 Capital report owning in Tango Therapeutics (TNGX)?
EcoR1 Capital, LLC reports zero shares of Tango Therapeutics common stock beneficially owned, corresponding to 0% of the class. The filing also shows no sole or shared voting power and no dispositive power over Tango shares as of December 31, 2025.
Which investors are listed as reporting persons in this Tango Therapeutics (TNGX) Schedule 13G/A?
The reporting persons are EcoR1 Capital, LLC, EcoR1 Capital Fund Qualified, L.P., and Oleg Nodelman. Each reports zero beneficial ownership in Tango Therapeutics common stock and a 0% stake in the issuer’s outstanding common shares as of December 31, 2025.
What percentage of Tango Therapeutics (TNGX) does EcoR1 Capital now own?
EcoR1 Capital, LLC reports owning 0% of Tango Therapeutics’ common stock. The amended Schedule 13G/A states zero shares beneficially owned and confirms ownership of 5 percent or less of the class, removing EcoR1 from significant shareholder status thresholds.
Are EcoR1 Capital and Oleg Nodelman filing as a group for Tango Therapeutics (TNGX)?
The filing says EcoR1 Capital Fund Qualified, L.P. is filing jointly with the other reporting persons but expressly disclaims membership in a group. Each reporting person also disclaims beneficial ownership of the securities except to the extent of any pecuniary interest.
What is the event date for EcoR1’s amended ownership report in Tango Therapeutics (TNGX)?
The event requiring the amended statement is dated December 31, 2025. As of that date, EcoR1 Capital, LLC, EcoR1 Capital Fund Qualified, L.P., and Oleg Nodelman each report 0 shares beneficially owned and 0% of Tango’s common stock outstanding.
How does this Schedule 13G/A affect EcoR1’s status in Tango Therapeutics (TNGX)?
The Schedule 13G/A shows EcoR1 and related reporting persons now own 5 percent or less of Tango Therapeutics’ common stock, with each reporting 0 shares. This means they no longer appear as significant beneficial owners under the 5% reporting threshold.
