Private Equity

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Femto Partners

Femto Partners is a private equity based in Tokyo, founded 2017; the Altss profile covers its classification, headquarters, registration, AUM band, and key...

Femto Partners logo

Femto Partners

Femto Partners is a Tokyo-based independent firm that focuses on growth equity and venture capital strategies across Japan.

General information

Firm type

Private Equity

Year founded

2017

Location

Region

Asia

Country

Japan

City

Tokyo

Corporate office

東京都港区南青山一丁目1番1号 新青山ビル東館19階, Tokyo, Japan

Principals

磯崎 哲也

Founder & General Partner

曽我 悠平

General Partner

大久保 克彦

Managing Partner

Sector focus

Enterprise Software

Frequently asked questions

What is Femto's track record in Japanese VC performance benchmarks?

In December 2025, Femto ranked first in the 7th Domestic VC Performance Benchmark survey for the 2024 vintage year. The firm self-reported the ranking on its website. No independent verification of the underlying methodology or peer set is publicly available.

Who runs investment decisions at Femto Partners?

Founder and General Partner Tetsuya Isozaki leads the firm alongside General Partner Yuhei Soga and Managing Partner Katsuhiko Okubo. The eight-person team operates without a separate investment committee disclosed publicly; principals Isozaki and Soga appear as the primary decision-makers based on firm materials.

Profile maintained by using OSINT (open-source intelligence), regulatory filings, licensed data partners, and verified direct submissions. Read the methodology. Last updated: . Continuous refresh with full update cycles at least every 30 days.

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