HOWL director-linked funds sell 139,803 shares

Werewolf Therapeutics director-affiliated funds reported open-market sales of 139,803 shares of Common Stock over three days.

Rhea-AI Filing Summary

Werewolf Therapeutics director-affiliated funds reported open-market sales of 139,803 shares of Common Stock over three days. Entities associated with Luke Evnin sold 80,459 shares on June 1 at a weighted average price of $0.47, 29,595 shares on June 2 at $0.45, and 29,749 shares on June 3 at $0.42 per share.

The transactions were executed pursuant to a Rule 10b5-1 trading plan dated March 26, 2026, and are reported as indirect ownership. After the June 3 transactions, the affiliated entities collectively held 482,776 shares, and Evnin disclaims beneficial ownership except to the extent of his pecuniary interest.

Insider Trade Summary 10b5-1

Net Seller: 139,803 shares

Net Sell 3 txns

Insider EVNIN LUKE

Role Director

Sold 139,803 shs ($64K)

Type	Security	Shares	Price	Value
Sale	Common Stock	29,749	$0.42	$12K
Sale	Common Stock	29,595	$0.45	$13K
Sale	Common Stock	80,459	$0.47	$38K

Holdings After Transaction: Common Stock — 482,776 shares (Indirect, See Footnotes)

Footnotes (11)

1. F1. Transaction effected pursuant to a plan established pursuant to Rule 10b5-1 dated March 26, 2026.
2. F2. The shares were sold as follows: 8,620 by MPM Asset Management LLC ("AM LLC"), 54,428 by MPM BioVentures 2014, L.P. ("BV 2014"), 3,630 by MPM BIoVentures 2014(B), L.P. ("BV 2014(B)"), 1,873 by MPM Asset Management Investors BV2014 LLC ("AM BV2014") and 11,908 by MPM Oncology Innovations Fund, L.P. ("MPM OIF").
3. F3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.45 to $0.495 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 range set forth in this footnote.
4. F4. MPM BioVentures 2014 GP LLC and MPM BioVentures 2014 LLC ("BV LLC") are the direct and indirect general partners of BV 2014 and BV 2014(B). BV LLC is the manager of AM BV2014. MPM Oncology Innovations Fund GP LLC ("MPM OIF GP") is the general partner of MPM OIF. Luke Evnin is a member of AM LLC, a Managing Director of BV LLC and a manager of MPM OIF GP. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein.
5. F5. The shares are held as follows: 58,081 by AM LLC, 366,727 by BV 2014, 24,458 by BV 2014(B), 12,620 by AM BV2014 and 80,234 by MPM OIF.
6. F6. The shares were sold as follows: 3,171 by AM LLC, 20,020 by BV 2014, 1,335 by BV 2014(B), 689 by AM BV2014 and 4,380 by MPM OIF.
7. F7. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.4304 to $0.46 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 range set forth in this footnote.
8. F8. The shares are held as follows: 54,910 by AM LLC, 346,707 by BV 2014, 23,123 by BV 2014(B), 11,931 by AM BV2014 and 75,854 by MPM OIF.
9. F9. The shares were sold as follows: 3,187 by AM LLC, 20,124 by BV 2014, 1,342 by BV 2014(B), 693 by AM BV2014 and 4,403 by MPM OIF.
10. F10. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.42 to $0.4367 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 range set forth in this footnote.
11. F11. The shares are held as follows: 51,723 by AM LLC, 326,583 by BV 2014, 21,781 by BV 2014(B), 11,238 by AM BV2014 and 71,451 by MPM OIF.

Key Figures

Total shares sold: 139,803 shares June 1 shares sold: 80,459 shares June 2 shares sold: 29,595 shares +2 more

5 metrics

Total shares sold 139,803 shares Aggregate open-market sales June 1–3, 2026

June 1 shares sold 80,459 shares Common Stock sold at weighted avg price $0.47

June 2 shares sold 29,595 shares Common Stock sold at weighted avg price $0.45

June 3 shares sold 29,749 shares Common Stock sold at weighted avg price $0.42

Holdings after sales 482,776 shares Indirectly held by affiliated entities after June 3, 2026

Key Terms

Rule 10b5-1, weighted average price, pecuniary interest, indirect ownership, +1 more

5 terms

Rule 10b5-1 regulatory

"Transaction effected pursuant to a plan established pursuant to Rule 10b5-1 dated March 26, 2026."

Rule 10b5-1 is a regulation that allows company insiders to buy or sell their shares at predetermined times, even if they have access to non-public information. It acts like setting a schedule in advance for transactions, helping prevent accusations of unfair trading. This rule provides a way for insiders to plan trades transparently, giving investors confidence that these transactions are not based on hidden information.

weighted average price financial

"The price reported in Column 4 is a weighted average price."

Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.

pecuniary interest financial

"The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein."

indirect ownership financial

"The shares are held as follows: 58,081 by AM LLC, 366,727 by BV 2014..."

open-market sale financial

"transaction_action: "open-market sale" with transaction code "S" for Common Stock."

An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.

FAQ

AI-generated questions and answers. How Rhea-AI works. Not financial advice.

What insider transactions did HOWL report for Luke Evnin-linked entities?

Entities associated with director Luke Evnin reported selling 139,803 shares of Werewolf Therapeutics Common Stock. The sales occurred over three days at weighted average prices between $0.42 and $0.47 per share, reflecting routine open-market activity by investment vehicles he is associated with.

Over what dates did the HOWL insider sales by affiliated funds occur?

The affiliated funds sold Werewolf Therapeutics shares on June 1, June 2, and June 3, 2026. Each day’s transactions involved open-market sales reported at weighted average prices, with detailed price ranges disclosed in the accompanying footnotes to the Form 4 filing.

How many HOWL shares were sold on each transaction date?

The affiliated entities sold 80,459 Werewolf Therapeutics shares on June 1, 29,595 shares on June 2, and 29,749 shares on June 3, 2026. These sales together total 139,803 shares of Common Stock reported as indirect holdings linked to Luke Evnin.

What prices were received in the recent HOWL insider share sales?

The reported weighted average sale prices were $0.47 per share on June 1, $0.45 on June 2, and $0.42 on June 3, 2026. Footnotes note that actual trade prices fell within specified ranges around each weighted average value for the day.

How many HOWL shares remain held by the Evnin-affiliated entities after these sales?

After the June 3, 2026 transactions, the affiliated investment entities collectively held 482,776 Werewolf Therapeutics shares. Footnotes break this down among several MPM-related vehicles, and Luke Evnin disclaims beneficial ownership beyond his pecuniary interest in those holdings.

Were the HOWL insider sales executed under a Rule 10b5-1 trading plan?

Yes. One footnote states the transactions were effected pursuant to a Rule 10b5-1 plan dated March 26, 2026. Such pre-arranged trading plans allow insiders or associated entities to sell shares on a predetermined schedule, helping separate trading decisions from day-to-day company information.

AI-generated analysis. How Rhea-AI works. Not financial advice.

Form 4 Insider Transactions: What Each Field Means →

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Accepted by SEC EDGAR 06/03/2026 - 06:42 PM EDT Learn about SEC filing dates

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).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

EVNIN LUKE

(Last) (First) (Middle)

C/O MPM BIOIMPACT LLC

399 BOYLSTON STREET, SUITE 1100

(Street)

BOSTON MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Werewolf Therapeutics, Inc. [ HOWL ]

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
06/01/2026

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

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

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

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	06/01/2026		S(1)		80,459(2)	D	$0.47(3)	542,120	I	See Footnotes(4)(5)
Common Stock	06/02/2026		S(1)		29,595(6)	D	$0.45(7)	512,525	I	See Footnotes(4)(8)
Common Stock	06/03/2026		S(1)		29,749(9)	D	$0.42(10)	482,776	I	See Footnotes(4)(11)

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

Explanation of Responses:

1. Transaction effected pursuant to a plan established pursuant to Rule 10b5-1 dated March 26, 2026.

2. The shares were sold as follows: 8,620 by MPM Asset Management LLC ("AM LLC"), 54,428 by MPM BioVentures 2014, L.P. ("BV 2014"), 3,630 by MPM BIoVentures 2014(B), L.P. ("BV 2014(B)"), 1,873 by MPM Asset Management Investors BV2014 LLC ("AM BV2014") and 11,908 by MPM Oncology Innovations Fund, L.P. ("MPM OIF").

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.45 to $0.495 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 range set forth in this footnote.

4. MPM BioVentures 2014 GP LLC and MPM BioVentures 2014 LLC ("BV LLC") are the direct and indirect general partners of BV 2014 and BV 2014(B). BV LLC is the manager of AM BV2014. MPM Oncology Innovations Fund GP LLC ("MPM OIF GP") is the general partner of MPM OIF. Luke Evnin is a member of AM LLC, a Managing Director of BV LLC and a manager of MPM OIF GP. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein.

5. The shares are held as follows: 58,081 by AM LLC, 366,727 by BV 2014, 24,458 by BV 2014(B), 12,620 by AM BV2014 and 80,234 by MPM OIF.

6. The shares were sold as follows: 3,171 by AM LLC, 20,020 by BV 2014, 1,335 by BV 2014(B), 689 by AM BV2014 and 4,380 by MPM OIF.

7. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.4304 to $0.46 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 range set forth in this footnote.

8. The shares are held as follows: 54,910 by AM LLC, 346,707 by BV 2014, 23,123 by BV 2014(B), 11,931 by AM BV2014 and 75,854 by MPM OIF.

9. The shares were sold as follows: 3,187 by AM LLC, 20,124 by BV 2014, 1,342 by BV 2014(B), 693 by AM BV2014 and 4,403 by MPM OIF.

10. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.42 to $0.4367 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 range set forth in this footnote.

11. The shares are held as follows: 51,723 by AM LLC, 326,583 by BV 2014, 21,781 by BV 2014(B), 11,238 by AM BV2014 and 71,451 by MPM OIF.

	/s/ Luke Evnin	06/03/2026
	** 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.
* Form 4: SEC 1474 (03-26)