Werewolf Therapeutics (HOWL) entities linked to Luke Evnin sell 76,928 shares

Filing Impact

(Neutral)

Filing Sentiment

(Negative)

Form Type

Rhea-AI Filing Summary

Werewolf Therapeutics, Inc. reported an insider transaction involving entities associated with director Luke Evnin. These entities executed an open-market sale of 76,928 shares of common stock at a weighted average price of $0.37 per share, pursuant to a pre-established Rule 10b5-1 trading plan dated March 26, 2026.

The shares were sold across several MPM-affiliated investment entities and, following the transaction, those entities collectively held 300,283 shares of Werewolf Therapeutics common stock. Evnin reports these holdings indirectly and disclaims beneficial ownership except to the extent of his pecuniary interest.

Insider Trade Summary 10b5-1

Net Seller: 76,928 shares ($28,463)

Net Sell 1 txn

Insider EVNIN LUKE

Role null

Sold 76,928 shs ($28K)

Type	Security	Shares	Price	Value
Sale	Common Stock	76,928	$0.37	$28K

Holdings After Transaction: Common Stock — 300,283 shares (Indirect, See Footnotes)

Footnotes (1)

Transaction effected pursuant to a plan established pursuant to Rule 10b5-1 dated March 26, 2026. The shares were sold as follows: 8,242 by MPM Asset Management LLC ("AM LLC"), 52,039 by MPM BioVentures 2014, L.P. ("BV 2014"), 3,471 by MPM BIoVentures 2014(B), L.P. ("BV 2014(B)"), 1,791 by MPM Asset Management Investors BV2014 LLC ("AM BV2014") and 11,385 by MPM Oncology Innovations Fund, L.P. ("MPM OIF"). The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $0.3553 to $0.3851 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. 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. The shares are held as follows: 32,171 by AM LLC, 203,135 by BV 2014, 13,546 by BV 2014(B), 6,989 by AM BV2014 and 44,442 by MPM OIF.

Key Figures

Shares sold: 76,928 shares Average sale price: $0.37 per share Post-transaction holdings: 300,283 shares +5 more

8 metrics

Shares sold 76,928 shares Open-market sale on June 9, 2026

Average sale price $0.37 per share Weighted average price for reported sale

Post-transaction holdings 300,283 shares Indirectly held by associated entities after sale

Price range of trades $0.3553–$0.3851 Range of individual trade prices in sale

Shares sold by BV 2014 52,039 shares Portion of total sold by MPM BioVentures 2014, L.P.

Shares held by BV 2014 203,135 shares Indirect holdings after transaction

Shares sold by AM LLC 8,242 shares Portion of total sold by MPM Asset Management LLC

Shares held by AM LLC 32,171 shares Indirect holdings after transaction

Key Terms

Rule 10b5-1, weighted average price, beneficial ownership, pecuniary interest, +2 more

6 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.

beneficial ownership financial

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

Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.

pecuniary interest financial

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

general partner financial

"MPM BioVentures 2014 GP LLC and MPM BioVentures 2014 LLC are the direct and indirect general partners of BV 2014 and BV 2014(B)."

A general partner is the person or firm that runs an investment partnership and legally represents it — they make the day-to-day decisions, choose which assets to buy or sell, and are responsible for the partnership’s obligations. Investors care because the general partner’s judgment, risk-taking and fee and profit-sharing arrangements determine both the potential returns and the level of exposure to losses; think of the GP as the ship’s captain whose skill and honesty shape the voyage’s outcome.

indirect ownership financial

"The shares are held as follows: 32,171 by AM LLC, 203,135 by BV 2014..."

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

Add on Google

Form 4 Insider Transactions: What Each Field Means →

06/10/2026 - 05:20 PM

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).

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)
06/09/2026

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	06/09/2026		S⁽¹⁾		76,928⁽²⁾	D	$0.37⁽³⁾	300,283	I	See Footnotes⁽⁴⁾⁽⁵⁾

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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

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: 8,242 by MPM Asset Management LLC ("AM LLC"), 52,039 by MPM BioVentures 2014, L.P. ("BV 2014"), 3,471 by MPM BIoVentures 2014(B), L.P. ("BV 2014(B)"), 1,791 by MPM Asset Management Investors BV2014 LLC ("AM BV2014") and 11,385 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 $0.3553 to $0.3851 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: 32,171 by AM LLC, 203,135 by BV 2014, 13,546 by BV 2014(B), 6,989 by AM BV2014 and 44,442 by MPM OIF.

	/s/ Luke Evnin	06/10/2026
	** 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)

Source: View Original Filing on SEC EDGAR

FAQ

What insider transaction did Werewolf Therapeutics (HOWL) disclose for Luke Evnin?

Werewolf Therapeutics disclosed an insider transaction where entities associated with director Luke Evnin sold 76,928 shares of common stock. The sale was executed in the open market under a pre-established Rule 10b5-1 trading plan and reported as indirect ownership.

How many Werewolf Therapeutics (HOWL) shares were sold and at what price?

Entities linked to Luke Evnin sold 76,928 Werewolf Therapeutics common shares at a weighted average price of $0.37 per share. The sales occurred in multiple trades within a price range from $0.3553 to $0.3851, as disclosed in the filing footnotes.

Were Luke Evnin’s Werewolf Therapeutics (HOWL) sales made under a Rule 10b5-1 plan?

Yes. The filing states the transaction was effected under a Rule 10b5-1 trading plan dated March 26, 2026. Such plans are pre-arranged and designed to allow insiders to sell shares on a predetermined schedule, reducing discretion over trade timing.

How many Werewolf Therapeutics (HOWL) shares remain held by entities associated with Luke Evnin?

After the reported sale, entities associated with Luke Evnin collectively held 300,283 shares of Werewolf Therapeutics common stock. These shares are spread across several MPM-affiliated investment vehicles, and Evnin reports them as indirect holdings with a pecuniary interest disclaimer.

How are Luke Evnin’s indirect Werewolf Therapeutics (HOWL) holdings structured?

The filing explains that shares are held by multiple MPM-related entities, including AM LLC, BV 2014, BV 2014(B), AM BV2014, and MPM OIF. General partner and manager entities oversee these funds, and Evnin disclaims beneficial ownership beyond his pecuniary interest in them.