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Mutex raises ¥281.6M in Series A funding to expand its AI-powered medical billing SaaS, Reze, with participation from MTI Co., Ltd., MEDIPAL Innovation Investment Limited Partnership, and Nippon Management Co., Ltd.

PRIVATEOct 05, 2026

Amount Raised

¥282 Million

Round Type

Series A

BunkyoInformation TechnologySoftwareHealth CareArtificial IntelligenceSaasMachine Learning

Investors

Nippon Management Co., Ltd.MEDIPAL Innovation Investment Limited PartnershipMti Co., Ltd.

Description

Mutex, a Tokyo-based health-tech startup specializing in medical claims processing automation, has raised 281.6 million yen in a Series A funding round. This latest investment will be used to expand the adoption of its AI-powered medical billing SaaS, Reze, among medical institutions. Funds will also support product development for the complete automation of medical claims processing workflows. Mutex's innovative solutions aim to reduce administrative burdens and improve operational efficiency in healthcare facilities.

Company Information

Company

Mutex

Location

Bunkyo, Tokyo, Japan

About

Mutex is a software development company focused on AI-powered solutions for medical institutions. Its flagship product, Reze, is a SaaS platform designed to help medical institutions automate claim processing and improve operational management. By leveraging generative AI and machine learning, Reze simplifies administrative tasks and optimizes revenue for medical departments. Founded in 2022 and headquartered in Tokyo, Japan, Mutex aims to drive digital transformation in the healthcare sector.

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Funding Insights

What this usually means
Typical timeline to Series B
Series A companies typically raise their next round in 10-18 months

Mutex raised. Fundz records a round at a median of 3.6 minutes from the SEC filing, with the decision-maker attached.

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