# EDGAR Filing Document

**Accession Number:** 0001473930
**File Stem:** 0001473930-26-000005
**Filing Date:** 2026-1
**Character Count:** 8636
**Document Hash:** 456ccb68551767e01e37b045414cf266
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001473930-26-000005.hdr.sgml**: 20260114

**ACCESSION NUMBER**: 0001473930-26-000005

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20260112

**FILED AS OF DATE**: 20260114

**DATE AS OF CHANGE**: 20260114

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Foley Todd
- **CENTRAL INDEX KEY:** 0001473930

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-43047
- **FILM NUMBER:** 26534235

**MAIL ADDRESS:**
- **STREET 1:** 399 BOYLSTON STREET
- **STREET 2:** SUITE 1100
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02116
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Aktis Oncology, Inc.
- **CENTRAL INDEX KEY:** 0002035832
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 852584233
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 17 DRYDOCK AVENUE
- **STREET 2:** SUITE #17-401
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02210
- **BUSINESS PHONE:** 978-237-4380

**MAIL ADDRESS:**
- **STREET 1:** 17 DRYDOCK AVENUE
- **STREET 2:** SUITE #17-401
- **CITY:** BOSTON
- **STATE:** MA
- **ZIP:** 02210

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

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] 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**<sup>*</sup><br>Foley Todd<br><sub>(Last) (First) (Middle)</sub><br>C/O MPM BIOIMPACT LLC<br>399 BOYLSTON STREET, SUITE 1100<br><sub>(Street)</sub><br>BOSTON, MA 02116<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-01-12 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director [X] 10% Owner<br>[ ] Officer (give title below) [ ] Other (specify below)<br>_ _ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>Aktis Oncology, Inc. [ AKTS ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| Common Stock | 2026-01-12 |  | C |  | 597391<sup>(1)</sup> | A | <sup>(2)</sup> | 597391 | I | See Footnote<sup>(3)(4)</sup> |
| Common Stock | 2026-01-12 |  | C |  | 2688270<sup>(5)</sup> | A | <sup>(2)</sup> | 3285661 | I | See Footnote<sup>(3)(6)</sup> |
| Common Stock | 2026-01-12 |  | C |  | 716872<sup>(7)</sup> | A | <sup>(2)</sup> | 4002533 | I | See Footnote<sup>(3)(8)</sup> |
| Common Stock | 2026-01-12 |  | P |  | 232870<sup>(9)</sup> | A | $18 | 4235403 | I | See Footnote<sup>(3)(10)</sup> |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| Series Seed Redeemable Convertible Preferred Stock | <sup>(2)</sup> | 2026-01-12 |  | C |  |  | 2272727 | <sup>(2)</sup> | <sup>(2)</sup> | Common Stock | 597391 | 0<sup>(2)</sup> | 0 | I | See Footnote<sup>(1)(3)</sup> |
| Series A Redeemable Convertible Preferred Stock | <sup>(2)</sup> | 2026-01-12 |  | C |  |  | 10227273 | <sup>(2)</sup> | <sup>(2)</sup> | Common Stock | 2688270 | 0<sup>(2)</sup> | 0 | I | See Footnote<sup>(3)(5)</sup> |
| Series B Redeemable Convertible Preferred Stock | <sup>(2)</sup> | 2026-01-12 |  | C |  |  | 2727273 | <sup>(2)</sup> | <sup>(2)</sup> | Common Stock | 716872 | 0<sup>(2)</sup> | 0 | I | See Footnote<sup>(3)(7)</sup> |

---

### Footnotes:

(1) The shares of common stock were issued upon conversion as follows: 556,810 by MPM BioVentures 2018, L.P. ("BV 2018"), 29,593 by MPM BioVentures 2018 (B), L.P. ("BV 2018(B)") and 10,988 by MPM Asset Management Investors BV2018 LLC ("AM BV2018"). MPM BioVentures 2018 GP LLC and MPM BioVentures 2018 LLC ("BV2018 LLC") are the direct and indirect general partners of BV 2018 and
BV 2018(B). BV 2018 LLC is the manager of AM BV2018. The Reporting Person is a managing director of BV 2018 LLC.

(2) Each share of Series Seed Redeemable Convertible Preferred Stock, Series A Redeemable Convertible Preferred Stock and Series B Redeemable Convertible Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 3.8044-for-1 basis into the number of shares of Common Stock shown in Column 7 without payment of further consideration upon the closing of the initial public offering of the Issuer's Common Stock. The Series Seed Redeemable Convertible Preferred Stock, Series A Redeemable Convertible Preferred Stock and Series B Redeemable Convertible Preferred Stock had no expiration date.

(3) The Reporting Persons disclaim beneficial ownership of the securities except to the extent of his or its pecuniary interest therein.

(4) The shares are held as follows:  556,810 by BV 2018, 29,593 by BV 2018(B) and 10,988 by AM BV2018.

(5) The shares of common stock were issued upon conversion as follows:  2,505,648 by BV 2018, 133,170 by BV 2018(B) and 49,452 by AM BV2018.

(6) The shares are held as follows: 3,062,458 by BV 2018, 162,763 by BV 2018(B) and 60,440 by AM BV2018.

(7) The shares of common stock were issued upon conversion as follows:  668,173 by BV 2018, 35,512 by BV 2018(B) and 13,187 by AM BV2018.

(8) The shares are held as follows: 3,730,631 by BV 2018, 198,275 by BV 2018(B) and 73,627 by AM BV2018.

(9) The shares were purchased as follows: 219,897 by BV 2018, 8,689 by BV 2018(B) and 4,284 by AM BV2018.

(10) The shares are held as follows: 3,950,528 by BV 2018, 206,964 by BV 2018(B) and 77,911 by AM BV2018.

**Signature:** /sTodd Foley  
**Date:** 2026-01-14

### Remarks:

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.**