Role
10%+ Owner
Signature
Pontifax Management 4 G.P. (2015) Ltd., By: /s/ Tomer Kariv, Chief Executive Officer
Issuer symbol
KROS
Transactions as of
15 Oct 2025
Transactions value $
-$84,975,125
Form type
4
Filing time
17 Oct 2025, 17:53:28 UTC
Previous filing
16 Sep 2025

Reporting Owners (8)

Name Relationship Address Signature Signature date CIK
Pontifax Management 4 G.P. (2015) Ltd. 10%+ Owner 14 SHENKAR STREET, BEIT OFEK, HERZLIYA PITUACH, ISRAEL Pontifax Management 4 G.P. (2015) Ltd., By: /s/ Tomer Kariv, Chief Executive Officer 17 Oct 2025 0001726334
Pontifax (Israel) IV, L.P. 10%+ Owner 14 SHENKAR STREET, BEIT OFEK, HERZLIYA PITUACH, ISRAEL Pontifax (Israel) IV L.P., By: /s/ Tomer Kariv, Chief Executive Officer 17 Oct 2025 0001726039
Pontifax (Cayman) IV L.P. 10%+ Owner 4 SHENKAR STREET, BEIT OFEK, HERZLIYA PITUACH, ISRAEL Pontifax (Cayman) IV L.P., By: /s/ Tomer Kariv, Chief Executive Officer 17 Oct 2025 0001726029
Pontifax (China) IV L.P. 10%+ Owner 14 SHENKAR STREET, BEIT OFEK, HERZLIYA PITUACH, ISRAEL Pontifax (China) IV L.P., By: /s/ Tomer Kariv, Chief Executive Officer 17 Oct 2025 0001726030
Pontifax Late Stage Fund L.P. 10%+ Owner 14 SHENKAR STREET, BEIT OFEK, HERZLIYA PITUACH, ISRAEL Pontifax Late Stage Fund, L.P., By: /s/ Asaf Shinar, Chief Financial Officer 17 Oct 2025 0001793769
Pontifax Late Stage GP Ltd. 10%+ Owner 14 SHENKAR STREET, BEIT OFEK, HERZLIYA PITUACH, ISRAEL Pontifax Late Stage GP Ltd., By: /s/ Asaf Shinar, Chief Financial Officer 17 Oct 2025 0001793770
Kariv Tomer Director, 10%+ Owner C/O PONTIFAX MANAGEMENT 4 GP (2015) LTD., 14 SHENKAR STREET, BEIT OFEK, HERZLIYA PITUACH, ISRAEL /s/ Tomer Kariv 17 Oct 2025 0001568077
Nussbaum Ran Director, 10%+ Owner C/O PONTIFAX MANAGEMENT 4 GP (2015) LTD., 14 SHENKAR STREET, BEIT OFEK, HERZLIYA PITUACH, ISRAEL /s/ Ran Nussbaum 17 Oct 2025 0001609805

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction KROS Common Stock, $0.0001 par value per share Sale -$40.6M -2.28M -100% $17.75 0 15 Oct 2025 By Pontifax (Israel) IV, L.P. F1
transaction KROS Common Stock, $0.0001 par value per share Sale -$19.9M -1.12M -100% $17.75 0 15 Oct 2025 By Pontifax (Cayman) IV, L.P. F2
transaction KROS Common Stock, $0.0001 par value per share Sale -$21.8M -1.23M -100% $17.75 0 15 Oct 2025 By Pontifax (China) IV, L.P. F3
transaction KROS Common Stock, $0.0001 par value per share Sale -$2.76M -155K -100% $17.75 0 15 Oct 2025 By Pontifax Late Stage Fund, L.P. F4
holding KROS Common Stock, $0.0001 par value per share 5.25K 15 Oct 2025 By Tomer Kariv F5
holding KROS Common Stock, $0.0001 par value per share 5.25K 15 Oct 2025 By Ran Nussbaum F5
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Pontifax Management 4 G.P. (2015) Ltd. is no longer subject to Section 16 filing requirements. Form 4 or Form 5 obligations may continue.

Explanation of Responses:

Id Content
F1 The securities are held by Pontifax (Israel) IV, L.P. ("Israel IV"). Pontifax Management 4 G.P. (2015) Ltd. ("Management 4") is the ultimate general partner of Israel IV. As a result, Management 4 may be deemed to share voting and dispositive power with respect to the shares held by Israel IV. Each of Tomer Kariv and Ran Nussbaum is a Managing Partner of Management 4 and, as a result, Messrs. Kariv and Nussbaum may be deemed to share voting and investment power with respect to the shares held by Israel IV. Management 4 and Messrs. Kariv and Nussbaum disclaim beneficial ownership of such shares, except to the extent of his or its pecuniary interest therein, and the inclusion of the shares in this report shall not be deemed to be an admission of beneficial ownership of the reported shares for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise.
F2 The securities are held by Pontifax (Cayman) IV, L.P. ("Cayman IV"). Management 4 is the ultimate general partner of Cayman IV. As a result, Management 4 may be deemed to share voting and dispositive power with respect to the shares held by Cayman IV. Each of Tomer Kariv and Ran Nussbaum is a Managing Partner of Management 4 and, as a result, Messrs. Kariv and Nussbaum may be deemed to share voting and investment power with respect to the shares held by Cayman IV. Management 4 and Messrs. Kariv and Nussbaum disclaim beneficial ownership of such shares, except to the extent of his or its pecuniary interest therein, and the inclusion of the shares in this report shall not be deemed to be an admission of beneficial ownership of the reported shares for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise.
F3 The securities are held by Pontifax (China) IV, L.P. ("China IV"). Management 4 is the ultimate general partner of China IV. As a result, Management 4 may be deemed to share voting and dispositive power with respect to the shares held by China IV. Each of Tomer Kariv and Ran Nussbaum is a Managing Partner of Management 4 and, as a result, Messrs. Kariv and Nussbaum may be deemed to share voting and investment power with respect to the shares held by China IV. Management 4 and Messrs. Kariv and Nussbaum disclaim beneficial ownership of such shares, except to the extent of his or its pecuniary interest therein, and the inclusion of the shares in this report shall not be deemed to be an admission of beneficial ownership of the reported shares for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise.
F4 The securities are held by Pontifax Late Stage Fund, L.P. ("Late Stage"). Pontifax Late Stage GP Ltd. ("Late Stage GP") is the general partner of Late Stage and the sole shareholder of Late Stage GP is Mr. Shlomo Karako. Pursuant to the Strategic Alliance Agreement, dated August 9, 2018, between Late Stage, Israel IV, Cayman IV and China IV (collectively the, "Pontifax IV Funds"), Late Stage invests side-by-side with the Pontifax IV Funds. By virtue of the strategic relationship, Management 4 and Tomer Kariv and Ran Nussbaum may be deemed to share voting and dispositive power with respect to the shares held by Late Stage in a manner similar to the voting and investment power with respect to the shares held by each of the Pontifax IV Funds. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of his or its pecuniary interest therein.
F5 In connection with the Stock Purchase Agreement, dated October 15, 2025, by and among certain of the Reporting Persons and the Issuer and the resignations of each of Tomer Kariv and Ran Nussbaum from the Issuer's board of directors, the Issuer accelerated the vesting of the restricted stock unit awards and certain options held by Messrs. Kariv and Nussbaum that were previously reported in their respective Form 4 filings.