Day One Biopharmaceuticals, Inc.
Total Trades
164
Buys
6
Sells
111
Largest Trade
N/A
Insiders
13
Institutional Funds
140
Inst. Value
$1M+
Activist Filings
30
Insider Trades
| Insider | Title | Type | Value | Shares | Price | Date |
|---|---|---|---|---|---|---|
| Bender Jeremy | CEO | SELL | $50K–$100K | 3K | $20.00 | Jul 20, 2022 |
| Grant Papanek Julie | Director | SELL | $15K–$50K | 1K | $20.00 | Jul 12, 2022 |
| York Charles N II | COO | SELL | $15K–$50K | 1K | $20.00 | Jul 12, 2022 |
| Bender Jeremy | CEO | SELL | $15K–$50K | 2K | $20.00 | Jul 12, 2022 |
| York Charles N II | COO | SELL | $15K–$50K | 2K | $20.00 | Jul 7, 2022 |
| Grant Papanek Julie | Director | SELL | $15K–$50K | 2K | $20.00 | Jul 7, 2022 |
| Blackman Samuel C. | Chief Medical Offi… | SELL | $100K–$500K | 10K | $18.72 | Jul 7, 2022 |
| Bender Jeremy | CEO | SELL | $50K–$100K | 3K | $20.00 | Jul 7, 2022 |
| Atlas Venture Opportunity Fund II, L.P. | 10% Owner | BUY | $1M+ | 767K | $15.00 | Jun 22, 2022 |
| Gladstone Michael | Director | BUY | $1M+ | 767K | $15.00 | Jun 22, 2022 |
| AI Day1 LLC | 10% Owner | BUY | $1M+ | 1.2M | $15.00 | Jun 21, 2022 |
| Blackman Samuel C. | Chief Medical Offi… | SELL | $500K+ | 50K | $16.26 | Jun 18, 2022 |
| AI Day1 LLC | 10% Owner | BUY | $1M+ | 107K | $14.52 | Jan 20, 2022 |
| Blackman Samuel C. | Chief Medical Offi… | SELL | $100K–$500K | 10K | $17.10 | Jan 6, 2022 |
Institutional Ownership
13F filings as of Dec 31, 2025 · 140 funds holding
| Fund | Shares | Value | Type |
|---|---|---|---|
| Atlas Venture Life Science Advisors, LLC | 6.4M | $1M+ | SH |
| STATE STREET CORP | 4.3M | $1M+ | SH |
| Pictet Asset Management Holding SA | 3.0M | $1M+ | SH |
| Hudson Bay Capital Management LP | 1.7M | $1M+ | SH |
| GEODE CAPITAL MANAGEMENT, LLC | 1.6M | $1M+ | SH |
| BALYASNY ASSET MANAGEMENT L.P. | 1.5M | $1M+ | SH |
| RENAISSANCE TECHNOLOGIES LLC | 1.3M | $1M+ | SH |
| Jefferies Financial Group Inc. | 1.1M | $1M+ | SH |
| DIMENSIONAL FUND ADVISORS LP | 979K | $1M+ | SH |
| MAK CAPITAL ONE LLC | 826K | $1M+ | SH |
| JACOBS LEVY EQUITY MANAGEMENT, INC | 729K | $1M+ | SH |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | 634K | $1M+ | SH |
| SCHRODER INVESTMENT MANAGEMENT GROUP | 570K | $1M+ | SH |
| Pale Fire Capital SE | 544K | $1M+ | SH |
| KENNEDY CAPITAL MANAGEMENT LLC | 543K | $1M+ | SH |
| AIGH Capital Management LLC | 540K | $1M+ | SH |
| BNP PARIBAS FINANCIAL MARKETS | 453K | $1M+ | SH |
| HRT FINANCIAL LP | 451K | $1M+ | SH |
| BlackRock, Inc. | 432K | $1M+ | SH |
| SG Americas Securities, LLC | 350K | $1M+ | SH |
Activist & 5%+ Owners
SC 13D/13G filings — investors holding 5%+ of outstanding shares
SC 13G/A · Feb 5, 2026
5.6%
5.7M shares
SC 13G/A · Nov 5, 2025
9.9%
10.1M shares
SC 13G/A · Aug 14, 2025
0.0%
0 shares
SC 13G/A · Aug 6, 2025
11.2%
11.3M shares
SC 13G · Jul 17, 2025
5.8%
5.8M shares
SC 13G/A · Apr 28, 2025
4.7%
4.8M shares
SC 13G/A · Feb 14, 2025
5.7%
5.8M shares
SC 13G/A · Feb 12, 2025
12.8%
12.9M shares
SC 13G/A · Nov 14, 2024
5.5%
4.8M shares
SC 13G/A · Nov 7, 2024
11.2%
11.3M shares
SC 13G · Nov 7, 2024
7.5%
7.4M shares
SC 13D/A · Aug 5, 2024
13.2%
12.9M shares
SC 13G/A · Feb 14, 2024
9.0%
7.8M shares
The Vanguard Group - 23-1945930
SC 13G · Feb 13, 2024
5.5%
4.8M shares
SC 13G · Jan 29, 2024
5.9%
5.1M shares
SC 13D/A · Oct 20, 2023
14.9%
12.9M shares
SC 13G/A · Aug 10, 2023
6.9%
6.0M shares
SC 13D/A · Jun 12, 2023
13.2%
11.5M shares
SC 13G/A · Feb 14, 2023
9.6%
7.0M shares
SC 13G/A · Feb 14, 2023
8.2%
6.0M shares
Takeda Pharmaceutical Company Limited
SC 13G/A · Feb 3, 2023
0.0%
0 shares
Takeda Pharmaceutical Company Limited
SC 13G/A · Feb 3, 2023
0.0%
0 shares
SC 13D/A · Nov 2, 2022
3.5%
2.5M shares
SC 13D/A · Oct 19, 2022
6.5%
4.7M shares
SC 13D/A · Sep 22, 2022
9.5%
7.0M shares
SC 13D/A · Sep 19, 2022
12.7%
9.3M shares
SC 13G · Sep 12, 2022
11.3%
8.3M shares
SC 13D/A · Jun 21, 2022
14.6%
10.7M shares
SC 13G · Feb 11, 2022
11.6%
7.2M shares
Takeda Pharmaceutical Company Limited
SC 13G · Jan 14, 2022
9.7%
6.0M shares