Adam Dubow - Aug 15, 2025 Form 4 Insider Report for Day One Biopharmaceuticals, Inc. (DAWN)

Role
Gen Counsel & Secretary
Signature
/s/ Charles N. York II, as Attorney-in-Fact
Stock symbol
DAWN
Transactions as of
Aug 15, 2025
Transactions value $
-$29,538
Form type
4
Date filed
8/19/2025, 07:38 PM
Previous filing
May 19, 2025
Next filing
Nov 7, 2025
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Dubow Adam Gen Counsel & Secretary 1800 SIERRA POINT PARKWAY, SUITE 200, BRISBANE /s/ Charles N. York II, as Attorney-in-Fact 2025-08-19 0001744507

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction DAWN Common Stock Options Exercise +2.96K +6.29% 50.1K Aug 15, 2025 Direct F1
transaction DAWN Common Stock Options Exercise +1.75K +3.49% 51.8K Aug 15, 2025 Direct F1
transaction DAWN Common Stock Options Exercise +3.69K +7.11% 55.5K Aug 15, 2025 Direct F1
transaction DAWN Common Stock Options Exercise +3.69K +6.64% 59.2K Aug 15, 2025 Direct F1
transaction DAWN Common Stock Sale -$29.5K -4.37K -7.37% $6.77 54.9K Aug 18, 2025 Direct F2, F3

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction DAWN Restricted Stock Unit (RSU) Options Exercise $0 -2.96K -16.67% $0.00 14.8K Aug 15, 2025 Common Stock 2.96K Direct F1, F4, F5
transaction DAWN Restricted Stock Unit (RSU) Options Exercise $0 -1.75K -16.67% $0.00 8.75K Aug 15, 2025 Common Stock 1.75K Direct F1, F5, F6
transaction DAWN Restricted Stock Unit (RSU) Options Exercise $0 -3.69K -10% $0.00 33.2K Aug 15, 2025 Common Stock 3.69K Direct F1, F5, F6
transaction DAWN Restricted Stock Unit (RSU) Options Exercise $0 -3.69K -7.14% $0.00 47.9K Aug 15, 2025 Common Stock 3.69K Direct F1, F5, F6
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Each Restricted Stock Unit ("RSU") represents a contingent right to receive one share of the Issuer's Common Stock upon settlement for no consideration.
F2 The sale of shares is for the sole purpose of covering the Reporting Person's tax liability with respect to the settlement of RSUs.
F3 The price reported in Column 4 is a weighted average price. These shares were sold as part of block trades for multiple security holders of the Issuer at prices ranging from $6.65 to $6.87, inclusive. The Reporting Person undertakes to provide to the Issuer, any securityholder 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 herein with regard to the block trade.
F4 The RSUs vest as to 25% of the total award on November 15, 2023, and 1/12th of the remaining amount vest in quarterly installments thereafter on February 15, May 15, August 15 and November 15, subject to the Reporting Person's provision of service to the Issuer on each vesting date.
F5 RSUs do not expire; they either vest or are canceled prior to the vesting date.
F6 The RSUs will vest as to 1/16th of the total award in quarterly installments on February 15, May 15, August 15 and November 15, subject to the Reporting Person's provision of service to the Issuer on each vesting date.