Callisto

What Callisto does

Callisto Inc. is a Tokyo-based medical imaging data platform company founded in 2022 that sources de-identified radiology, pathology, clinical, and molecular datasets from Japanese medical institutions and distributes them to AI developers, pharmaceutical companies, medical device manufacturers, and academic researchers. Its core product, the Callisto DataHub, launched in March 2024 and operates alongside a data processing pipeline covering anonymization, standardization, selection, and expert annotation, producing datasets that include radiology reports and verified ground-truth labels suitable for AI training, regulatory submissions, clinical research, and drug evidence generation.

The company monetizes through one-time dataset licensing on the self-service DataHub platform, contract AI development and consulting services for drug discovery and medical imaging, and a revenue-sharing arrangement with its partner medical institutions that aligns supply-side incentives. Go-to-market combines direct enterprise sales for custom curation and consulting with self-service dataset purchases via medical-datahub.ai, supported by exhibition activity at major industry events including RSNA and ITEM/JRC. Callisto reports 20+ customers across the US, Europe, South Korea, and Japan, has been named a finalist in two 2025 healthcare venture contests, and has begun deploying capital externally as a co-investor in adjacent health-tech ventures.

Name

Callisto

Legal name

Callisto Inc.

Website

https://callisto-ai.com

Company type

Private

Founded year

2022

Operating status

Operating

Headcount range

11–50 employees

Short description

Callisto is a Tokyo-based medical imaging data platform that sources de-identified radiology, pathology, clinical, and molecular datasets from Japanese medical institutions and licenses them, with expert annotations, to medical AI companies, pharmaceutical firms, medical device manufacturers, and academic researchers worldwide.

Ownership category

akta.pro rank

Product category

Medical Imaging Data Platform

NAICS

Research and Development in Biotechnology (except Nanobiotechnology) (541714)

SIC

Services-Commercial Physical & Biological Research (8731)

akta.pro primary industry

Cellomics & High-Content Screening (HCS) Services (HLAGANAD)

akta.pro secondary industry

Diagnostic/Lab & Imaging Referral Marketplaces (HLALALAG)

Keywords

• Medical imaging datasets
• Clinical research data
• AI training datasets
• Radiology data platform
• Drug discovery AI

Headquarters

HQ city

Nishi

HQ country

Japan

HQ region

Asia

Offices1 record

Markets served

GTM type

B2B

Offering type

Software

Cost components

Personnel, Technology or R&D, Operations, Marketing or Sales, Others

Revenue model

1. Medical Image Dataset Sales: Sale of de-identified medical imaging datasets (radiology, pathology, clinical, molecular) to AI companies, pharmaceutical companies, medical device manufacturers, and academic institutions. Datasets include expert annotations and are available for commercial use with accompanying radiology reports.
2. Contract AI Development and Consulting: Custom AI development services for drug discovery and healthcare applications, including consulting engagements with pharmaceutical partners.
3. Institutional Revenue Sharing: Revenue sharing model with partner medical institutions to build a sustainable data ecosystem. Datasets are derived from Japanese medical facilities and revenue is shared with partner institutions.

Pricing tiers

Go-to-market motion1 record

Distribution channels2 records

Marketing channels3 records

Core offering

Callisto operates a medical imaging data platform (Callisto DataHub) that distributes de-identified radiology, pathology, clinical, and molecular datasets sourced from Japanese medical institutions. The datasets are processed through anonymization, standardization, and expert annotation, and are licensed to AI companies, pharmaceutical companies, medical device manufacturers, and academic institutions for AI training, evaluation, regulatory submissions, clinical research, and drug evidence generation. The company also offers contract AI development and consulting services for drug discovery and medical AI.

Product overview

Callisto operates as a medical imaging data platform company offering a unified portfolio anchored by the Callisto DataHub platform. The platform distributes de-identified medical image datasets (including chest X-rays, MRI, pathology slides, and molecular data) sourced from Japanese medical institutions. The portfolio includes two specific annotated dataset products—the lung cancer chest X-ray dataset and prostate cancer MRI dataset—both featuring expert lesion annotations and radiology reports. Additional offerings include contract development and consulting services for AI-driven drug discovery and medical AI. All products support uses ranging from AI model training and evaluation to regulatory submissions, clinical research, and marketing.

Differentiator

Problem solved

Functional benefit

Brands

• Callisto DataHub: Medical imaging data platform for AI and clinical research, offering de-identified radiology, pathology, clinical, and molecular datasets sourced from Japanese medical institutions.

Products and services

• Callisto DataHub A medical imaging data distribution platform that provides de-identified radiology, pathology, clinical, and molecular datasets from Japanese medical institutions. The platform supports medical AI training, evaluation, regulatory submissions, clinical research, drug evidence generation, and marketing applications, with datasets available for commercial use.
• Lung Cancer Chest X-ray Dataset A collection of 50 annotated chest X-ray cases with lung cancer suspected findings, including lesion bounding boxes and accompanying radiology reports. Sourced from Japanese medical institutions and available for commercial use.
• Prostate Cancer MRI Dataset A collection of 50 annotated MRI cases with prostate cancer findings, including lesion segmentations and accompanying radiology reports. Sourced from Japanese medical institutions and available for commercial use.
• AI-Driven Drug Discovery and Medical AI Development Services Contract development and consulting services for AI-driven drug discovery and medical AI development, leveraging the company's processed medical imaging datasets to support pharmaceutical R&D, drug evidence generation, and custom medical AI builds.

Quantifiable outcome

• 15+ medical AI companies, pharmaceutical companies, medical device manufacturers, and academic institutions using the platform across 4 regions

Named customers4 records

Segments4 records

Ideal customer profiles4 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

AI capability2 records

Feature3 records

Scale indicators4 records

Recent moves6 records

Expansion highlights5 records

Direct peers

• Segmed: Segmed operates a medical imaging data marketplace that aggregates de-identified radiology datasets from healthcare institutions for AI development—the closest direct peer to Callisto in business model and customer base.
• Centaur Labs: Centaur Labs labels medical images at scale using expert annotators for AI training, addressing the same medical imaging data preparation need for AI developers and med-device companies.
• V7 Labs: V7 Labs builds a data labeling and dataset management platform with strong medical imaging support; it competes for both the annotation tooling and curated dataset portion of Callisto's offering.
• MD.ai: MD.ai provides a medical imaging collaboration and annotation platform used by hospitals and AI developers; directly comparable as a data infrastructure layer for imaging-based AI training.
• Encord: Encord offers data curation, annotation, and quality assurance tooling for AI teams including a dedicated medical imaging workflow; it competes for the same AI/medical imaging data buyer.

Broad incumbents

• Scale AI: Scale AI operates a broad data labeling platform with a dedicated Scale Medical offering; a much larger, broad-based incumbent in medical imaging annotation compared to Callisto's niche focus.
• Tempus Labs: Tempus is a large precision-medicine data and AI platform serving pharma and providers with proprietary datasets; it represents the vertically integrated incumbent that could either partner with or compete against Callisto in pharma R&D data.
• Labelbox: Labelbox is a broad data platform for cataloging, annotation, and model evaluation with healthcare as a key vertical; a cross-vertical incumbent that overlaps with Callisto's data tooling and curation layer.
• Sama: Sama delivers high-quality data annotation services with an explicit healthcare/medical imaging practice, serving many of the same enterprise medical AI and med-device buyers as Callisto.
• Appen: Appen provides large-scale data annotation and dataset services including healthcare-relevant data, representing a well-funded broad incumbent competing for enterprise medical data procurement budgets.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat3 records

Key risks6 records

Key highlights6 records

Customer concentration

Revenue estimate

Valuation estimate

Number of profiles

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Callisto