Willett Advisors is a single-family office that manages the personal and philanthropic assets of Michael R. Bloomberg, including Bloomberg Philanthropies. Its investment strategy focuses on achieving long-term capital appreciation through a diversified portfolio across public markets, private equity, real assets, hedge funds, and direct investments, often with an emphasis on impact-oriented strategies.
86% of their portfolio is in Biotech & Life Sciences. They made 2 investments in the last 12 months. Their most common stage is series-b (43% of deals). Average disclosed round size is $127.4M (across 7 rounds with reported amounts).
Portfolio
7
Fund Size
$25B
Top Stage
Series B
Last 12 Mo
2
Portfolio Breakdown
Stage Distribution
Sector Distribution
Investment Activity
DealsAvg Round Size
Portfolio
7 investments
| Company | Round | Amount | Date |
|---|---|---|---|
 Kinaset Therapeutics | Series B | $103M | Jan 2026 |
| AAAVantgarde Bio | Series B | $141M | Nov 2025 |
 Remix Therapeutics | Series C | $60M | Jan 2024 |
 Cellares | Series C | $255M | Aug 2023 |
 Carmot Therapeutics | Series E | $150M | May 2023 |
 Disc Medicine | Series B | $90M | Sep 2021 |
 TraceLink Inc. | Series D | $93M | Aug 2018 |
Top Co-Investors
Atlas Venture4 shared
Schroders Capital2 shared
Sixty Degree Capital2 shared
Janus Henderson Investors2 shared
Alexandria Venture Investments2 shared
RA Capital Management2 shared
The Column Group2 shared
Forbion1 shared
ATHOS1 shared
CDP Venture Capital1 shared
NEVA SGR1 shared
OrbiMed1 shared
Arix Bioscience1 shared
Rock Springs Capital1 shared
Novo Holdings1 shared
Access Biotechnology1 shared
Deep Track Capital1 shared
Franklin Templeton1 shared
Frazier Life Sciences1 shared
Millennium Management1 shared
Last updated: 16 April 2026