| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| EVNIN LUKE | Director | C/O MPM BIOIMPACT LLC, 399 BOYLSTON STREET, SUITE 1100, BOSTON | /s/ Luke Evnin | 03 Nov 2025 | 0001134657 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | HOWL | Common Stock | Sale | -$79.8K | -55.8K | -1.35% | $1.43 | 4.08M | 30 Oct 2025 | See Footnote | F1, F2, F3, F4 |
| transaction | HOWL | Common Stock | Sale | -$93.7K | -73.2K | -1.8% | $1.28 | 4M | 31 Oct 2025 | See Footnote | F1, F5, F6, F7 |
| transaction | HOWL | Common Stock | Sale | -$77.9K | -60.4K | -1.51% | $1.29 | 3.94M | 03 Nov 2025 | See Footnote | F1, F8, F9, F10 |
Buy Plan / Sale Plan: These are also open market purchases/sales of shares, but in this case the transaction is part of a trading plan. Rule 10b5-1 allows insiders to setup a trading plan to buy/sell stocks over a certain period of time. Since the purchases/sales are predetermined, this protects the insiders from violating insider trading law.
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).
| Id | Content |
|---|---|
| F1 | Transaction effected pursuant to a plan established pursuant to Rule 10b5-1 dated September 24, 2025. |
| F2 | The shares were sold as follows: 5,969 by MPM Asset Management LLC ("AM LLC"), 37,709 by MPM BioVentures 2014, L.P. ("BV 2014"), 2,515 by MPM BioVentures 2014(B), L.P. (BV 2014(B), 1,298 MPM Asset Management Investors BV2014 LLC ("AM BV2014") and 8,304 by MPM Oncology Innovations Fund, L.P. ("MPM OIF"). 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. |
| F3 | The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $1.365 to $1.55 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. |
| F4 | The shares are held as follows: 436,489 by AM LLC, 2,756,691 by BV 2014, 183,866 by BV 2014(B), 94,885 by AM BV2014 and 604,989 by MPM OIF. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. |
| F5 | The were sold as follows: 7,830 by AM LLC, 49,467 by BV 2014, 3,299 by BV 2014(B), 1,702 by AM BV2014 and 10,894 by MPM OIF. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. |
| F6 | The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $1.205 to $1.415 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. |
| F7 | The shares are held as follows: 428,659 by AM LLC, 2,707,224 by BV 2014, 180,567 by BV 2014(B), 93,183 by AM BV2014 and 594,095 by MPM OIF. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. |
| F8 | The shares were sold as follows: 6,458 by AM LLC, 40,800 by BV 2014, 2,721 by BV 2014(B), 1,405 by AM BV2014 and 8,985 by MPM OIF. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. |
| F9 | The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $1.245 to $1.33 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. |
| F10 | . The shares are held as follows: 422,201 by AM LLC, 2,666,424 by BV 2014, 177,846 by BV 2014(B), 91,778 by AM BV2014 and 585,110 by MPM OIF. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. |