0001415889-24-009146.txt : 20240326 0001415889-24-009146.hdr.sgml : 20240326 20240326180924 ACCESSION NUMBER: 0001415889-24-009146 CONFORMED SUBMISSION TYPE: 4 PUBLIC DOCUMENT COUNT: 1 CONFORMED PERIOD OF REPORT: 20240325 FILED AS OF DATE: 20240326 DATE AS OF CHANGE: 20240326 REPORTING-OWNER: OWNER DATA: COMPANY CONFORMED NAME: Blackman Samuel C. CENTRAL INDEX KEY: 0001863676 ORGANIZATION NAME: FILING VALUES: FORM TYPE: 4 SEC ACT: 1934 Act SEC FILE NUMBER: 001-40431 FILM NUMBER: 24785143 MAIL ADDRESS: STREET 1: 395 OYSTER POINT BLVD. STREET 2: SUITE 217 CITY: SOUTH SAN FRANCISCO STATE: CA ZIP: 94080 ISSUER: COMPANY DATA: COMPANY CONFORMED NAME: Day One Biopharmaceuticals, Inc. CENTRAL INDEX KEY: 0001845337 STANDARD INDUSTRIAL CLASSIFICATION: PHARMACEUTICAL PREPARATIONS [2834] ORGANIZATION NAME: 03 Life Sciences IRS NUMBER: 832415215 STATE OF INCORPORATION: DE FISCAL YEAR END: 1231 BUSINESS ADDRESS: STREET 1: 2000 SIERRA POINT PARKWAY, SUITE 501 CITY: BRISBANE STATE: CA ZIP: 94005 BUSINESS PHONE: 650 484-0899 MAIL ADDRESS: STREET 1: 2000 SIERRA POINT PARKWAY, SUITE 501 CITY: BRISBANE STATE: CA ZIP: 94005 FORMER COMPANY: FORMER CONFORMED NAME: Day One Biopharmaceuticals Holding Co LLC DATE OF NAME CHANGE: 20210209 4 1 form4-03262024_100315.xml X0508 4 2024-03-25 0001845337 Day One Biopharmaceuticals, Inc. DAWN 0001863676 Blackman Samuel C. 2000 SIERRA POINT PARKWAY, SUITE 501 BRISBANE CA 94005 false true false false HEAD OF R&D 1 Common Stock 2024-03-25 4 S 0 10000 16.0055 D 1184662 D Common Stock 1000000 I See footnote The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on October 10, 2023. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $16.00 to $16.04 per share, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder 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 in this footnote. The Reporting Person is the sole manager, and has shared voting and dispositive power with his wife as members. The Reporting Person continues to report beneficial ownership of all of the Issuer's Common Stock held by the 2021 Blackman Family LLC but disclaims beneficial ownership except to the extent of his and his wife's pecuniary interest therein. /s/ Charles N. York II, as Attorney-in-Fact 2024-03-26