[Form 4] Tango Therapeutics, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Third Rock Ventures entities reported an insider sale of Tango Therapeutics (TNGX) common stock. On 09/16/2025 the reporting persons sold 363,541 shares at a weighted-average price of $7.04 per share (sales ranged $7.00–$7.19). After the sale, Third Rock Ventures IV, L.P. directly held 14,363,975 shares. The filing identifies the reporting parties as a director and a greater-than-10% owner and includes standard GP disclaimers that the GP entities disclaim beneficial ownership except to the extent of pecuniary interest. The Form 4 was signed by Kevin Gillis on 09/17/2025.

Positive

• Reporting parties retain a substantial position of 14,363,975 shares after the sale, indicating continued material ownership.
• Transaction fully disclosed with weighted-average price and price range, plus signature and GP disclaimers, reflecting compliance with Section 16 reporting requirements.

Negative

• Insider sale of 363,541 shares on 09/16/2025 could be interpreted as a reduction in insider holdings in the near term.

Insights

Securities Analyst

TL;DR: A major holder and director reduced stock by 363,541 shares at ~$7.04, but retains a large 14.36M-share position.

The sale is clearly disclosed and executed across multiple transactions at prices between $7.00 and $7.19, producing a weighted-average of $7.04. The reporting entities remain a substantial holder with 14,363,975 shares following the transactions, which preserves significant economic exposure to Tango Therapeutics. The GP-level disclaimers are standard and limit attribution of beneficial ownership to pecuniary interest. For investors, this is a routine Section 16 disclosure of insider sales rather than an operational or financial disclosure by the issuer.

Corporate Governance Expert

TL;DR: Insider sale properly reported under Section 16; governance disclosures and GP disclaimers are in order.

The Form 4 includes required signatures and the explanatory footnotes describing weighted-average pricing and ownership structure. The multiple related reporting entities and GP disclaimers are common in venture-backed settings; they clarify that the limited partner vehicle directly holds the shares while GP entities disclaim beneficial ownership except as to pecuniary interest. The filing shows compliance with reporting obligations and transparent presentation of the transaction details.

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
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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)
09/16/2025

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	09/16/2025		S		363,541	D	$7.04(1)	14,363,975	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 $7.00 to $7.19, 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.	09/17/2025
	/s/ Kevin Gillis, Chief Operating Officer of TRV GP IV, LLC, general partner of Third Rock Ventures GP IV, L.P.	09/17/2025
	/s/ Kevin Gillis, Chief Operating Officer of TRV GP IV, LLC	09/17/2025
	** 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.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

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

The filer sold 363,541 shares of Tango Therapeutics common stock on 09/16/2025 at a weighted-average price of $7.04 per share (sales ranged $7.00–$7.19).

How many Tango Therapeutics shares does Third Rock Ventures still hold after the sale?

After the reported transactions, Third Rock Ventures IV, L.P. directly held 14,363,975 shares.

Who signed the Form 4 and when was it filed?

The Form 4 was signed by Kevin Gillis and the signature date shown is 09/17/2025.

Are the general partner entities claiming beneficial ownership of the shares?

The filing states that TRV GP IV and TRV GP IV LLC disclaim beneficial ownership of the shares except to the extent of any pecuniary interest, and the shares are directly held by Third Rock Ventures IV, L.P.

Does the Form 4 indicate any derivative transactions or options?

No. Table II (derivatives) contains no reported transactions; only the non-derivative sale of common stock is reported.