Third Rock sells Tango shares, cutting stake to 4.74% (TNGX)

Rhea-AI Filing Summary

Tango Therapeutics, Inc. filed an Amendment No. 4 to Schedule 13D/A reporting updated ownership by Third Rock Ventures entities. As of February 6, 2026, Third Rock Ventures IV, L.P. and its affiliated general partners reported shared voting and dispositive power over 6,374,574 shares of Tango common stock, representing approximately 4.74% of outstanding shares, based on 134,593,998 shares outstanding as of October 28, 2025. The amendment states that transactions described in Item 5(c) caused a decrease of over one percentage point in the aggregate ownership previously reported. These changes follow several open-market sales of Tango shares in January and February 2026.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 4)

Tango Therapeutics, Inc.

(Name of Issuer)

Common Stock

(Title of Class of Securities)

87583X109

(CUSIP Number)

Third Rock Ventures, LLC
201 Brookline Avenue, Suite 1401
Boston, MA, 02215
617-585-2000

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

02/06/2026

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

CUSIP No. 87583X109

1

Name of reporting person

Third Rock Ventures IV, L.P.

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

WC

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 6,374,574.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 6,374,574.00

11

Aggregate amount beneficially owned by each reporting person

6,374,574.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

4.74 %

14

Type of Reporting Person (See Instructions)

PN

Comment for Type of Reporting Person:

The percent of class was calculated based on 134,593,998 shares of common stock issued and outstanding as of October 28, 2025, as disclosed in the Issuer's 10-Q filed with the Securities and Exchange Commission on November 4, 2025.

SCHEDULE 13D

CUSIP No. 87583X109

1

Name of reporting person

Third Rock Ventures GP IV, L.P.

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

AF

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 6,374,574.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 6,374,574.00

11

Aggregate amount beneficially owned by each reporting person

6,374,574.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

4.74 %

14

Type of Reporting Person (See Instructions)

PN

Comment for Type of Reporting Person:

The percent of class was calculated based on 134,593,998 shares of common stock issued and outstanding as of October 28, 2025, as disclosed in the Issuer's 10-Q filed with the Securities and Exchange Commission on November 4, 2025.

SCHEDULE 13D

CUSIP No. 87583X109

1

Name of reporting person

TRV GP IV, LLC

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

AF

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 6,374,574.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 6,374,574.00

11

Aggregate amount beneficially owned by each reporting person

6,374,574.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

4.74 %

14

Type of Reporting Person (See Instructions)

OO

Comment for Type of Reporting Person:

The percent of class was calculated based on 134,593,998 shares of common stock issued and outstanding as of October 28, 2025, as disclosed in the Issuer's 10-Q filed with the Securities and Exchange Commission on November 4, 2025.

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: Common Stock
(b)	Name of Issuer: Tango Therapeutics, Inc.
(c)	Address of Issuer's Principal Executive Offices: 201 Brookline Avenue, Suite 1401, Boston, MASSACHUSETTS , 02215.
Item 1 Comment: This Amendment No. 4 (this "Amendment") amends and supplements the Schedule 13D (as amended, the "Schedule 13D") filed by the Reporting Persons with respect to the shares of common stock, $0.001 par value per share ("Common Stock"), of Tango Therapeutics, Inc. (the "Company" or the "Issuer"). The transactions described in Item 5(c) resulted in a decrease of over one percent (1%) in the aggregate percentage ownership reported by the Reporting Persons in the Schedule 13D. Except as specifically provided herein, this Amendment does not modify any of the information previously reported in the Schedule 13D.
Item 5.	Interest in Securities of the Issuer
(a)	As of February 6, 2026, TRV IV had shared voting and dispositive power with respect to 6,374,574 shares of the Issuer's Common Stock, constituting approximately 4.74% of the Issuer's outstanding Common Stock. As of February 6, 2026, Third Rock Ventures GP IV, L.P. ("TRV GP IV"), as the general partner of TRV IV may be deemed to have shared voting and dispositive power with respect to all 6,374,574 shares of the Issuer's Common Stock owned by TRV IV, constituting approximately 4.74% of the Issuer's outstanding Common Stock. As of February 6, 2026, TRV GP IV, LLC ("TRV GP IV LLC," and collectively with TRV IV and TRV GP IV, the "Reporting Persons"), as the general partner of TRV GP IV may be deemed to have shared voting and dispositive power with respect to all 6,374,574 shares of the Issuer's Common Stock owned by TRV IV, constituting approximately 4.74% of the Issuer's outstanding Common Stock. The percent of class was calculated based on 134,593,998 shares of common stock issued and outstanding as of October 28, 2025, as disclosed in the Issuer's 10-Q filed with the Securities and Exchange Commission on Novemebr 4, 2025. Except as set forth in the table below, no transactions in the Common Stock were effected by the Reporting Persons during the 60-day period ended February 6, 2026. Date Amount of Securities Price per Share Where and How Effected TRV IV 1/21/2026 350,000 $12.52* Disposed in the Open Market TRV IV 1/22/2026 253,383 $12.56* Disposed in the Open Market TRV IV 2/3/2026 500,000 $12.59* Disposed in the Open Market TRV IV 2/6/2026 396,617 $12.57* Disposed in the Open Market * The price reported is a weighted average price. These shares were sold in multiple transactions.
(b)	Regarding the number of shares as to which such person has: (i) sole power to vote or to direct the vote: See line 7 of cover sheets (ii) shared power to vote or to direct the vote: See line 8 of cover sheets (iii) sole power to dispose or to direct the disposition: See line 9 of cover sheets. (iv) shared power to dispose or to direct the disposition: See line 10 of cover sheets
(c)	Except as set forth in the table below, no transactions in the Common Stock were effected by the Reporting Persons during the 60-day period ended February 6, 2026.
(e)	2/6/2026

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.

Third Rock Ventures IV, L.P.

Signature:	/s/ Kevin Gillis
Name/Title:	Kevin Gillis, COO of TRV GP IV, LLC, the general partner of Third Rock Ventures GP IV, L.P., the general partner of Third Rock Ventures IV, L.P.
Date:	02/10/2026

Third Rock Ventures GP IV, L.P.

Signature:	/s/ Kevin Gillis
Name/Title:	Kevin Gillis, COO of TRV GP IV, LLC, the general partner of Third Rock Ventures GP IV, L.P.
Date:	02/10/2026

TRV GP IV, LLC

Signature:	/s/ Kevin Gillis
Name/Title:	Kevin Gillis, COO
Date:	02/10/2026

FAQ

What ownership stake in Tango Therapeutics (TNGX) does Third Rock now report?

Third Rock Ventures IV, L.P. and affiliates report beneficial ownership of 6,374,574 Tango Therapeutics common shares, constituting approximately 4.74% of the outstanding stock. That percentage is calculated using 134,593,998 shares outstanding as of October 28, 2025, from Tango’s Form 10-Q.

Why did Third Rock Ventures file Amendment No. 4 to its Schedule 13D for TNGX?

The amendment reflects a change in Third Rock’s percentage ownership of Tango Therapeutics common stock. Transactions described in Item 5(c) resulted in a decrease of over one percentage point in the aggregate ownership percentage previously reported by the reporting persons.

What recent Tango Therapeutics (TNGX) share sales did Third Rock report?

Third Rock Ventures IV, L.P. reported open market sales of Tango shares on January 21, January 22, February 3, and February 6, 2026. Individual trades included blocks such as 350,000 and 500,000 shares at weighted average prices around $12.52–$12.59.

How is the 4.74% ownership in Tango Therapeutics (TNGX) calculated?

The 4.74% figure uses 134,593,998 Tango common shares outstanding as of October 28, 2025. That share count comes from Tango’s Form 10-Q filed on November 4, 2025, and serves as the denominator for the Schedule 13D/A ownership calculation.

Which entities are the reporting persons in this Tango Therapeutics (TNGX) Schedule 13D/A?

The reporting persons are Third Rock Ventures IV, L.P., Third Rock Ventures GP IV, L.P., and TRV GP IV, LLC. Each entity is organized in Delaware and may be deemed to share voting and dispositive power over the same 6,374,574 Tango common shares held by Third Rock Ventures IV, L.P.

What voting and dispositive powers do Third Rock entities report over Tango Therapeutics (TNGX) shares?

The reporting persons disclose zero sole voting or dispositive power and shared voting and dispositive power over 6,374,574 shares. Third Rock Ventures IV, L.P. holds the shares, while its affiliated general partners may be deemed to share authority over voting and disposition.