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.
100% of their portfolio is in Biotech & Life Sciences. They made 1 investments in the last 12 months. Their most common stage is series-b (67% of deals). Average disclosed round size is $127.0M (across 3 rounds with reported amounts).
Portfolio
3
Fund Size
$25B
Top Stage
Series B
Last 12 Mo
1
Portfolio Breakdown
Stage Distribution
Investment Activity
DealsAvg Round Size
Portfolio
3 investments
| Company | Round | Amount | Date |
|---|---|---|---|
| AAAVantgarde Bio | Series B | $141M | Nov 2025 |
| CCarmot Therapeutics | Series E | $150M | May 2023 |
 Disc Medicine | Series B | $90M | Sep 2021 |
Top Co-Investors
Atlas Venture2 shared
Janus Henderson Investors2 shared
Forbion1 shared
Schroders Capital1 shared
ATHOS1 shared
CDP Venture Capital1 shared
NEVA SGR1 shared
Sixty Degree Capital1 shared
OrbiMed1 shared
Arix Bioscience1 shared
Rock Springs Capital1 shared
Alexandria Venture Investments1 shared
Novo Holdings1 shared
Access Biotechnology1 shared
Deep Track Capital1 shared
Franklin Templeton1 shared
Frazier Life Sciences1 shared
RA Capital Management1 shared
Millennium Management1 shared
The Column Group1 shared
Last updated: 5 March 2026