About D3
D3 is a venture capital firm founded in 2017. It is primarily based out of Tokyo, Japan. As of Apr 2026, D3 is an active investor, having invested in 5 companies, with 1 new investment in the last 12 months. It primarily invests in Series A round in Japan based startups. Its investments are spread across a wide range of sectors from Life Sciences to High Tech and HealthTech. Most recently it participated in the $***** Series A round of neumo A lot of funds co-invest with D3, with names like SBI Investment sharing a substantial percentage of its portfolio. D3 has team of 3 people including 2 partners.Key Metrics
Team Members
Portfolio Count
Portfolio Sectors
Portfolio Locations
Rounds of Entry
Series A & Series B
D3's List of All Investments
D3 has a portfolio of 5 companies. Their most notable investments are in RevolKa and RevolKa.Their portfolio spans across and Japan. They have invested in Life Sciences, High Tech, HealthTech and 1 other sectors, across stages such as Series A, Series B stages. Here is the list of all investments by D3:
1. Alpha Fusion
Developer of radiopharmaceuticals for cancer treatment. It offers a lead compound Astatine-211 that emits alpha particles that selectively target and destroy the cancer cells in the human body.
Key facts about Alpha Fusion
- Founded Year: 2021
- Location: Osaka (Japan)
- Stage: Series B
- Total Funding till date: $6.89M
- Investors: JGC Holdings Corporation, Osaka University Venture Capital and 7 Others
- Latest Funding Round: Series B, Oct 09, 2024, $*****
- Highlight: Editors' Pick

2. RevolKa
Key facts about RevolKa
- Founded Year: 2021
- Location: Chuo City (Japan)
- Stage: Series A
- Total Funding till date: $3.1M
- Employee Count: 12 as on Aug 31, 2026
- Investors: SBI Investment, Tohoku University Venture Partners and 3 Others
- Latest Funding Round: Series A, May 20, 2025, $*****

3. Thyas
Thyas is involved in developing iPSC technology to treat cancer. They have developed autologous adoptive immunotherapy with induced pluripotent stem cells (iPSC)-derived killer T cells. Their technology helps to convert the exhausted killer T immune cells to stem cells to produce new T cells which target cancer and other chronic infections.
Key facts about Thyas
- Founded Year: 2015
- Location: Kyoto (Japan)
- Stage: Series B
- Total Funding till date: $18.2M
- Employee Count: 3 as on Aug 31, 2026
- Investors: F-Prime Capital, Eight Roads Ventures and 2 Others
- Latest Funding Round: Series B, Feb 21, 2022, $*****
Wearable device for tracking muscle metabolism. The company has developed a wearable device to measure lactic acid concentration within sweat. It also offers MRI technique non-invasively measures for muscle tissue data, such as the separation of fast and slow muscles.
Key facts about Grace imaging
- Founded Year: 2018
- Location: Shinjuku City (Japan)
- Stage: Series A
- Total Funding till date: $3.53M
- Investors: QB Capital, Mitsubishi UFJ Capital and 4 Others
- Latest Funding Round: Series A, Jul 05, 2023, $*****
D3's Year-on-Year Investment Trends
D3 has invested in 5 companies over the last 4 years, with an average of 1 new investment annually in the last 3 years. In 2025, it made 1 investment, while as of Apr 2026, it has made 1 investment in this year. Its most recent first time investment was in neumo and most recent follow-on round was in RevolKa.Year | No. of Investments | ||
|---|---|---|---|
1st Round | Follow-on | Total | |
2026 (YTD) | 1 | 0 | 1 |
2025 | 0 | 1 | 1 |
2024 | 2 | 0 | 2 |
2023 | 1 | 0 | 1 |
2022 | 1 | 0 | 1 |
D3's Investments by Stage
D3 has made 3 investments in Series A stage with an average round size of $2.61M and 2 investments in Series B stage with an average round size of $12.6M.Stage of entry | No. of Investments |
|---|---|
Series A | 3 |
Series B | 2 |
Note: We have considered here, only first round of investments
D3's Investments by Sector
D3 has a diverse portfolio, with companies operating in the Healthcare, Life Sciences, HealthTech, High Tech and Internet of Things - Industry Applications. Notably, it has invested in 3 Tech companies, 2 Enterprise (B2B) companies, 1 Consumer (B2C) company and 1 company focusing on Tech hardware.Sector | No. of Investments |
|---|---|
Healthcare | 2 |
Life Sciences | 2 |
HealthTech | 1 |
High Tech | 1 |
Internet of Things - Industry Applications | 1 |
Note: We have considered here, only first round of investments
D3's Investments by Geography
D3 has made most investments in Japan (5).D3's recent investments
D3 has made 1 investments in 2026 so far - neumo.Here are the most recent investments by D3:
Date | Company | Location | Round Details | Round Amount | Co-Investors |
|---|---|---|---|---|---|
Apr 23, 2026 | Japan | Series A | 9886 | - | |
May 20, 2025 | Japan | Series A | 6702 | ||
Oct 09, 2024 | Japan | Series B | 4670 | [+5] | |
Aug 29, 2024 | Japan | Series A | 3194 | [+2] | |
Jul 05, 2023 | Japan | Series A | 7792 |
Team profile of D3
D3 has a team of 3 members including 2 Partners and 1 Venture Partner located in Japan. D3's team does not sit on the board of any company as of now.Here is a list of all team members in D3:
Name | Designation | Location | Board Memberships | Contact Details |
|---|---|---|---|---|
Partner | Japan | - | - | |
Partner | - | - | - | |
Venture Partner | Tokyo | - | - |
Co-investors of D3
Over the past 4 years, 16 investors have co-invested in D3's portfolio companies. This includes only funds.
- Invested before D3: Sumitomo Heavy Industries and JGC Mirai Innovation Fund have invested in rounds before D3. There is 1 company where Sumitomo Heavy Industries has invested before D3 and 1 company where JGC Mirai Innovation Fund has invested before D3.
- Top Co-investors of D3: 14 investors entered a company along with D3. These include investors like SBI Investment (2 companies).
Recent News related to D3
•
neumo, which develops the KIKUMORE hearing training app, raises fundsSogyo Techo•Apr 23, 2026•D3, Neumo
•
RevolKa Ltd. Secures Series A Extension FundingBusiness Wire•May 20, 2025•D3, RevolKa, Tohoku University Venture Partners, DEEPCORE
•
•
•
RevolKa secures funds for drug discovery programmesPharmaceutical Technology•Aug 30, 2024•RevolKa, D3, DEEPCORE
•
Shinobi Therapeutics Raises $51M in Series A FundingFinSMEs•Dec 12, 2023•Shinobi Therapeutics, D3, JIC Venture Growth Investments, FTI and 4 others


