Insider Sale: Third Rock Ventures Disposes 500,000 Tango Therapeutics Shares

Rhea-AI Filing Summary

Third Rock Ventures IV, L.P. reported a sale of 500,000 shares of Tango Therapeutics, Inc. (TNGX) executed on 09/25/2025 at a weighted-average price of $8.017 per share. After the sale, the reporting person holds 13,863,975 shares, which are directly held by Third Rock Ventures IV, L.P. The filing identifies Third Rock Ventures GP IV, L.P. and TRV GP IV, LLC as related entities that disclaim beneficial ownership except to the extent of any pecuniary interest. The form was signed by Kevin Gillis on 09/29/2025.

Positive

• Transparent disclosure of weighted-average sale price and offer to provide per-price details on request
• Ownership structure clarified with explicit disclaimers by general partner entities

Negative

• Insider sale of 500,000 shares, which reduces the reporting person's holdings to 13,863,975 shares
• Materiality of sale not contextualized by percentage of outstanding shares or prior holdings in the filing

Insights

Securities Analyst

TL;DR: A significant insider sale of 500,000 TNGX shares occurred at a weighted-average price of $8.017, reducing the reported stake to 13.86 million shares.

The transaction is a clear, disclosed disposition by a major holder tied to Third Rock Ventures IV, L.P. The report provides the weighted-average price range and offers to supply per-price breakdowns on request, which supports transparency. There is no additional company operational or financial information in this filing to assess broader implications.

Corporate Governance Expert

TL;DR: Routine Section 16 disclosure of a sale by an affiliated investment vehicle; related entities disclaim beneficial ownership.

The filing appropriately documents the sale and clarifies ownership structure: TRV IV directly holds the shares while its GP entities disclaim beneficial ownership except for pecuniary interest. Signatures are provided by an authorized officer. The filing contains no indication of changes to governance or management roles.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

Third Rock Ventures IV, L.P.

(Last) (First) (Middle)

C/O THIRD ROCK VENTURES, LLC

201 BROOKLINE AVE, SUITE 1401

(Street)

BOSTON MA 02215

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Tango Therapeutics, Inc. [ TNGX ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
09/25/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

	Form filed by One Reporting Person
X	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	09/25/2025		S		500,000	D	$8.017(1)	13,863,975	D(2)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person^*

Third Rock Ventures IV, L.P.

(Last) (First) (Middle)

C/O THIRD ROCK VENTURES, LLC

201 BROOKLINE AVE, SUITE 1401

(Street)

BOSTON MA 02215

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

Third Rock Ventures GP IV, L.P.

(Last) (First) (Middle)

201 BROOKLINE AVE, SUITE 1401

(Street)

BOSTON MA 02215

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

TRV GP IV, LLC

(Last) (First) (Middle)

201 BROOKLINE AVE, SUITE 1401

(Street)

BOSTON MA 02215

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

Explanation of Responses:

1. The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $8.00 to $8.165, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote (1).

2. These shares are directly held by Third Rock Ventures IV, L.P. ("TRV IV"). The general partner of TRV IV is Third Rock Ventures GP IV, L.P. ("TRV GP IV"). The general partner of TRV GP IV is TRV GP IV, LLC ("TRV GP IV LLC"). Each of TRV GP IV and TRV GP IV LLC disclaims beneficial ownership of the shares except to the extent of its pecuniary interest therein, if any, and this report shall not be deemed an admission that it is the beneficial owner of such shares.

	/s/ Kevin Gillis, Chief Operating Officer of TRV GP IV, LLC, general partner of Third Rock Ventures GP IV, L.P., general partner of Third Rock Ventures IV, L.P.	09/29/2025
	/s/ Kevin Gillis, Chief Operating Officer of TRV GP IV, LLC, general partner of Third Rock Ventures GP IV, L.P.	09/29/2025
	/s/ Kevin Gillis, Chief Operating Officer of TRV GP IV, LLC	09/29/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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FAQ

What transaction did Third Rock Ventures report for Tango Therapeutics (TNGX)?

The report discloses a sale of 500,000 common shares executed on 09/25/2025.

At what price were the TNGX shares sold in the Form 4?

The shares were sold at a weighted-average price of $8.017 per share, with individual trades ranging from $8.00 to $8.165.

How many TNGX shares does the reporting person hold after the sale?

After the reported sale, the reporting person directly holds 13,863,975 shares of TNGX.

Who signed the Form 4 for this transaction and when?

The Form 4 was signed by Kevin Gillis, Chief Operating Officer of TRV GP IV, LLC, on 09/29/2025.

Do the general partner entities claim beneficial ownership of the shares?

No. TRV GP IV and TRV GP IV LLC disclaim beneficial ownership except to the extent of any pecuniary interest, per the filing.