Key facts
- This page summarizes Norbert W. Bischofberger's Form 4 filing for Kronos Bio, Inc. (KRON).
- 9 reported transactions and 4 derivative rows are listed below.
- Accepted by SEC: 20 Jun 2025, 16:15.
Norbert W. Bischofberger - 20 Jun 2025 Form 4 Insider Report for Kronos Bio, Inc. (KRON)
- Reporting relationship
- Director, 10%+ Owner
- Issuer ticker
- KRON
- Reported as of
- 20 Jun 2025
- Net transaction value
- -$6,758,569
- SEC form
- 4
- Accepted by SEC
- 20 Jun 2025, 16:15:37 UTC
- Prior SEC filing
- 06 Jun 2025
- Next SEC filing
- 28 May 2026
- Source filing
- View source filing
- Reporting owner signature
- /s/ Norbert Bischofberger
Source evidence
Original filing metadata and source links for verification.
5 source fields
Reporting owner
1 detail
Key filing fact
Norbert W. Bischofberger filed Form 4 for Kronos Bio, Inc. (KRON) on 20 Jun 2025.
Change
- Previous filing in this sequence was filed on 06 Jun 2025.
- Current net transaction value: -$6,758,569.
Research use
- This tells you what this filing adds before you inspect full transaction and derivative tables.
- You can trace every row back to the original SEC filing document.
Evidence
Filed on Form 4
View source filing
Ownership activity is grounded in SEC Form 4 disclosures.
Reporting Owners (1)
CIK 0001190273
Primary reporting owner
BISCHOFBERGER NORBERT W
- Relationship
- Director, 10%+ Owner
- Address
- C/O KRONOS BIO, INC., 301 BINNEY STREET, 2ND FLOOR EAST, CAMBRIDGE
- Signature
- /s/ Norbert Bischofberger
- Signature date
- 20 Jun 2025
Reported non-derivative transactions
Shares, units, or other non-derivative securities reported in this filing.
KRON
transaction
Common Stock
Disposition pursuant to a tender of shares in a change of control transaction
- Transaction value
- $6,157,219
- Shares
- -10,802,138
- Change %
- -100%
- Price
- $0.5700
- Shares after
- 0
- Date
- 20 Jun 2025
- Ownership
- See Footnote
- Footnotes
- F1, F2, F3
KRON
transaction
Common Stock
Disposition pursuant to a tender of shares in a change of control transaction
- Transaction value
- $150,338
- Shares
- -263,750
- Change %
- -100%
- Price
- $0.5700
- Shares after
- 0
- Date
- 20 Jun 2025
- Ownership
- See Footnote
- Footnotes
- F1, F2, F4
KRON
transaction
Common Stock
Disposition pursuant to a tender of shares in a change of control transaction
- Transaction value
- $150,338
- Shares
- -263,750
- Change %
- -100%
- Price
- $0.5700
- Shares after
- 0
- Date
- 20 Jun 2025
- Ownership
- See Footnote
- Footnotes
- F1, F2, F5
KRON
transaction
Common Stock
Disposition pursuant to a tender of shares in a change of control transaction
- Transaction value
- $150,338
- Shares
- -263,750
- Change %
- -100%
- Price
- $0.5700
- Shares after
- 0
- Date
- 20 Jun 2025
- Ownership
- See Footnote
- Footnotes
- F1, F2, F6
KRON
transaction
Common Stock
Disposition pursuant to a tender of shares in a change of control transaction
- Transaction value
- $150,338
- Shares
- -263,750
- Change %
- -100%
- Price
- $0.5700
- Shares after
- 0
- Date
- 20 Jun 2025
- Ownership
- See Footnote
- Footnotes
- F1, F2, F7
Reported derivative securities
Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.
KRON
transaction
Derivative
Employee Stock Option (Right to Buy)
Disposed to Issuer
- Transaction value
- $0
- Shares
- -297,186
- Change %
- -100%
- Price
- $0.000000
- Shares after
- 0
- Date
- 20 Jun 2025
- Ownership
- Direct
- Underlying class
- Common Stock
- Underlying amount
- 297,186
- Exercise price
- $30.78
- Footnotes
- F8
KRON
transaction
Derivative
Employee Stock Option (Right to Buy)
Disposed to Issuer
- Transaction value
- $0
- Shares
- -400,000
- Change %
- -100%
- Price
- $0.000000
- Shares after
- 0
- Date
- 20 Jun 2025
- Ownership
- Direct
- Underlying class
- Common Stock
- Underlying amount
- 400,000
- Exercise price
- $7.30
- Footnotes
- F8
KRON
transaction
Derivative
Employee Stock Option (Right to Buy)
Disposed to Issuer
- Transaction value
- $0
- Shares
- -570,868
- Change %
- -100%
- Price
- $0.000000
- Shares after
- 0
- Date
- 20 Jun 2025
- Ownership
- Direct
- Underlying class
- Common Stock
- Underlying amount
- 570,868
- Exercise price
- $2.09
- Footnotes
- F8
KRON
transaction
Derivative
Employee Stock Option (Right to Buy)
Disposed to Issuer
- Transaction value
- $0
- Shares
- -699,800
- Change %
- -100%
- Price
- $0.000000
- Shares after
- 0
- Date
- 20 Jun 2025
- Ownership
- Direct
- Underlying class
- Common Stock
- Underlying amount
- 699,800
- Exercise price
- $1.08
- Footnotes
- F8
* marks a reported price that did not pass the local price check.
Additional SEC filing notes
Filing notes and footnotes
Section 16 status
Norbert W. Bischofberger is no longer subject to Section 16 filing requirements. Form 4 or Form 5 obligations may still apply in specific circumstances.
Explanation of responses 8 footnotes
Footnote F1
Disposed of pursuant to the Agreement and Plan of Merger (the "Merger Agreement"), dated as of May 1, 2025, by and among Kronos Bio, Inc. (the "Issuer"), Concentra Biosciences, LLC ("Parent") and Concentra Merger Sub IV, Inc., a wholly owned subsidiary of Parent ("Merger Sub"). On June 18, 2025, Parent and Merger Sub completed a tender offer pursuant to the terms of the Merger Agreement for all outstanding shares of common stock of the Issuer (each, a "Share") for an offer price of (i) $0.57 per Share in cash (the "Cash Amount"), and (ii) one non-transferable contractual contingent value right (each, a "CVR"), subject to and in accordance with the terms of the Contingent Value Rights Agreement (the "CVR Agreement"), in each case, without interest, and subject to any applicable withholding taxes (the Cash Amount plus one CVR, collectively, the "Offer Price").[continues to Footnote 2]
Footnote F2
[continues from Footnote 1] Merger Sub thereafter merged with and into the Issuer, with the Issuer continuing as the surviving corporation and a wholly owned subsidiary of Parent (the "Merger"). At the effective time of the Merger, each issued and outstanding Share (other than any Excluded Shares (as such term is defined in the Merger Agreement)) was cancelled in exchange for the right to receive the Offer Price.
Footnote F3
By the Norbert W. & Inger A. Bischofberger Revocable Inter Vivos Trust, dtd August 29, 1994,
Footnote F4
By the Norbert W. Bischofberger and Inger A. Bischofberger, Trustees of The David Michael Anthony Dynasty GST Exempt Trust dated April 29, 2020.
Footnote F5
By Norbert W. Bischofberger and Inger A. Bischofberger, Trustees of The David Michael Anthony Dynasty GST Non-Exempt Trust dated April 29, 2020.
Footnote F6
By Norbert W. Bischofberger and Inger A. Bischofberger, Trustees of The Irene Alisha Bischofberger Dynasty GST Exempt Trust dated April 29, 2020.
Footnote F7
By Norbert W. Bischofberger and Inger A. Bischofberger, Trustees of The Irene Alisha Bischofberger Dynasty GST Non-Exempt Trust dated April 29, 2020.
Footnote F8
As of immediately prior to and conditioned upon the effective time of the effective time of the Merger, pursuant to the Merger Agreement, each outstanding option to purchase Shares (each, an "Option") became fully vested and exercisable, and to the extent not exercised prior to the effective time of the Merger, was cancelled and converted into the right to receive (a) an amount in cash (without interest and subject to deduction for any required withholding tax) equal to the product of (1) the excess, if any, of the Cash Amount over the exercise price per share of each such Option and (2) the number of Shares underlying such Option immediately prior to the effective time of the Merger and (b) one CVR in respect of each Share underlying such Option; provided, however, that if the exercise price per Share of any Option was equal to or greater than the Cash Amount that was then outstanding it was cancelled for no consideration.