EcoR1, Nodelman detail Aktis Oncology (AKTS) Form 3 insider holdings

Rhea-AI Filing Summary

Aktis Oncology, Inc. (AKTS) filed a Form 3 for EcoR1 Capital, LLC and Oleg Nodelman, identifying them as a director and 10% owners. The filing reports indirect beneficial ownership of Series A and Series B redeemable convertible preferred stock held through EcoR1 Capital Fund Qualified, L.P., EcoR1 Capital Fund, L.P., and EcoR1 Venture Opportunity Fund, L.P. These preferred shares are immediately exercisable, have no expiration date, and will automatically convert into common stock on a 3.8044-for-1 basis immediately before the closing of the company’s initial public offering, with amounts reflecting a 1-for-3.8044 reverse stock split effective January 2, 2026.

The Form 3 also discloses a director stock option for 37,866 shares of common stock at an exercise price of $18, beneficially owned solely by Mr. Nodelman. One‑thirty‑sixth of the option vests in monthly installments from January 8, 2026, subject to his continuous service. The reporting persons are filing jointly, but state they are not a group and disclaim beneficial ownership of the securities except to the extent of their pecuniary interests.

SEC Form 3

FORM 3

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

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

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:			3235-0104
Estimated average burden
hours per response:			0.5

1. Name and Address of Reporting Person^*

EcoR1 Capital, LLC

(Last) (First) (Middle)

357 TEHAMA STREET #3

(Street)

SAN FRANCISCO CA 94103

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
01/08/2026

3. Issuer Name and Ticker or Trading Symbol
Aktis Oncology, Inc. [ AKTS ]

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

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

5. 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 Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Series A Redeemable Convertible Preferred Stock	(1)	(1)	Common Stock	2,605,878(2)	(1)	I	See note(3)
Series A Redeemable Convertible Preferred Stock	(1)	(1)	Common Stock	262,142(2)	(1)	I	See note(4)
Series A Redeemable Convertible Preferred Stock	(1)	(1)	Common Stock	128,506(2)	(1)	I	See note(5)
Series B Redeemable Convertible Preferred Stock	(1)	(1)	Common Stock	630,191(2)	(1)	I	See note(3)
Series B Redeemable Convertible Preferred Stock	(1)	(1)	Common Stock	26,942(2)	(1)	I	See note(4)
Director Stock Option (Right to Acquire)	(6)	01/07/2036	Common Stock	37,866	$18	D(7)

1. Name and Address of Reporting Person^*

EcoR1 Capital, LLC

(Last) (First) (Middle)

357 TEHAMA STREET #3

(Street)

SAN FRANCISCO CA 94103

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

NODELMAN OLEG

(Last) (First) (Middle)

357 TEHAMA STREET #3

(Street)

SAN FRANCISCO CA 94103

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

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

Explanation of Responses:

1. Shares of Series A Redeemable Convertible Preferred Stock and Series B Redeemable Convertible Preferred Stock are convertible into shares of Common Stock at the election of the holder. Each share is immediately exercisable and has no expiration date, but will be automatically converted on a 3.8044-for-1 basis into shares of Common Stock immediately prior to the closing of the initial public offering of the Issuer's Common Stock.

2. Reflects the number of shares of Common Stock issuable after the 1-for-3.8044 reverse stock split which became effective on January 2, 2026.

3. These securities are held by EcoR1 Capital Fund Qualified, L.P. ("Qualified Fund"). EcoR1 Capital, LLC ("EcoR1") may be deemed to indirectly beneficially own them as the investment adviser to and general partner of the fund. Mr. Nodelman may be deemed to indirectly beneficially own them as the control person of EcoR1.

4. These securities are held by EcoR1 Capital Fund, L.P. ("Capital Fund"). EcoR1 may be deemed to indirectly beneficially own them as the investment adviser to and general partner of the fund. Mr. Nodelman may be deemed to indirectly beneficially own them as the control person of EcoR1.

5. These securities are held by EcoR1 Venture Opportunity Fund, L.P. ("Venture Fund"). EcoR1 may be deemed to indirectly beneficially own them as the investment adviser to and general partner of the fund. Mr. Nodelman may be deemed to indirectly beneficially own them as the control person of EcoR1.

6. 1/36th of the original number of shares subject to the option shall vest in monthly installments from January 8, 2026, subject to Mr. Nodelman's continuous service through each vesting date, inclusive.

7. These securities are beneficially owned solely by Mr. Nodelman.

Remarks:

EcoR1 is the general partner and investment adviser of private funds, including Qualified Fund, Capital Fund and Venture Fund. Mr. Nodelman is a director of the issuer and is the manager and controlling owner of EcoR1. The reporting persons are filing this Form 3 jointly, but not as a group, and each expressly disclaims membership in a group within the meaning of Rule 13d-5(b) under the Securities Exchange Act of 1934. The reporting persons disclaim beneficial ownership of the securities reported herein, except to the extent of their respective pecuniary interests therein.

	/s/ Oleg Nodelman, Manager of EcoR1 Capital, LLC	01/08/2026
	** 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 5 (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 does the Aktis Oncology (AKTS) Form 3 filing by EcoR1 Capital and Oleg Nodelman report?

The Form 3 reports that EcoR1 Capital, LLC and Oleg Nodelman are directors and 10% owners of Aktis Oncology and disclose their beneficial interests in convertible preferred stock held through EcoR1-managed funds, plus a director stock option held by Mr. Nodelman.

How are EcoR1 Capital’s holdings in Aktis Oncology (AKTS) structured in this Form 3?

The filing states that Series A and Series B redeemable convertible preferred stock are held by three funds: EcoR1 Capital Fund Qualified, L.P., EcoR1 Capital Fund, L.P., and EcoR1 Venture Opportunity Fund, L.P., with EcoR1 as investment adviser and general partner and Mr. Nodelman as EcoR1’s control person.

What conversion terms apply to the preferred stock reported for Aktis Oncology (AKTS)?

The Series A and Series B redeemable convertible preferred stock are immediately exercisable, have no expiration date, and will automatically convert into common stock on a 3.8044-for-1 basis immediately prior to the closing of Aktis Oncology’s initial public offering, after a 1-for-3.8044 reverse stock split effective January 2, 2026.

What stock option does Oleg Nodelman hold in Aktis Oncology (AKTS) according to the Form 3?

Mr. Nodelman holds a director stock option for 37,866 shares of common stock at an exercise price of $18 per share. One‑thirty‑sixth of the original option amount vests monthly starting January 8, 2026, subject to his continuous service.

Do EcoR1 Capital and Oleg Nodelman claim full beneficial ownership of the Aktis Oncology (AKTS) securities?

No. The filing states that the reporting persons are filing jointly but not as a group and that they disclaim beneficial ownership of the securities reported, except to the extent of their respective pecuniary interests in the EcoR1-managed funds.

Why are EcoR1 Capital and Oleg Nodelman considered 10% owners of Aktis Oncology (AKTS)?

They are identified in the Form 3 as directors and 10% owners, reflecting their deemed beneficial interests in Aktis Oncology securities held through EcoR1-managed funds and Mr. Nodelman’s direct option position.