What Limbus AI does

Limbus AI is a Regina, Canada-based medical AI company that develops Limbus Contour, an on-premise deep learning auto-segmentation platform for radiation therapy treatment planning. The software processes CT and MR images on existing clinical workstations to automatically generate contours of organs at risk (OARs) and clinical target volumes (CTVs), supporting 260+ structures across Head & Neck, Thorax/Abdomen, and Pelvis anatomical sites. A zero-click automation workflow detects the treatment site, applies the appropriate clinical template, and exports compliant DICOM RT-Structure files to any treatment planning system without cloud transfer or GPU requirements, enabling typical contouring times of under 3 minutes on CPU and under 1 minute on GPU.

The company sells software licenses primarily to hospital radiation oncology departments, cancer centers, and clinics across Canada, the United States, the United Kingdom, Germany, Switzerland, and France, with documented customer outcomes including 55-75% reductions in dosimetrist and physician contouring time and 80% time savings for Head & Neck cases specifically. Marketing is research-driven, relying on peer-reviewed publications, webinars featuring medical physicists and radiation oncologists, and conference participation at ASTRO, ESTRO, and CARO rather than paid channels. Customer logos span academic centers (Universitätsspital Basel), regional hospitals (Pius Hospital Oldenburg, Asklepios Clinic Hamburg), and national health systems (Royal Devon and Exeter NHS Foundation Trust, BC Cancer).

On April 30, 2024, Limbus AI was acquired by Radformation, Inc., a US-based leader in cancer care automation, and now operates as a privately-held subsidiary. Limbus Contour was subsequently unified with Radformation's AutoContour into AutoContour v2.7, a single AI-driven contouring platform combining zero-click automation with seamless treatment planning system integration. The company had 1-10 employees at acquisition and had received a 2019 seed investment from Cultivator; revenue figures have not been publicly disclosed.

Name

Limbus AI

Website

https://limbus.ai

Company type

Private

Founded year

2017

Operating status

Acquired

Headcount range

1–10 employees

Short description

Limbus AI develops on-premise deep learning auto-segmentation software that automatically contours anatomical structures for radiation therapy treatment planning, serving hospital radiation oncology departments and cancer centers across North America and EMEA. Acquired by Radformation in April 2024.

Ownership category

akta.pro rank

Product category

Radiation Oncology Software

NAICS

Surgical and Medical Instrument Manufacturing (339112), Electromedical and Electrotherapeutic Apparatus Manufacturing (334510), Scientific Research and Development Services (5417)

SIC

Surgical & Medical Instruments & Apparatus (3841), Services-Computer Integrated Systems Design (7373), Services-Prepackaged Software (7372)

akta.pro primary industry

Radiology AI, CAD & Advanced Visualization Software (HLAHABAJ)

akta.pro secondary industries

Medical Imaging AI (HDAAAEAH), SaMD – Imaging & Signal Analysis (AI/ML) (HLACANAG), AI Orchestration & Imaging Analytics Platforms (Model Management/Triage) (HLACALAG), Interventional Radiology & Image-Guided Therapy Systems (HLAHABAG)

Keywords

• Radiation oncology software
• Auto-contouring software
• Deep learning segmentation
• Radiotherapy planning
• Medical imaging AI

Headquarters

HQ city

Regina

HQ country

Canada

HQ region

North America

Markets served

GTM type

B2B

Offering type

Software

Cost components

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

Revenue model

1. Software Licensing: The company sells software licenses for its Limbus Contour auto-contouring product. Software is installed on existing clinical workstations. The model implies either subscription or perpetual licensing with annual support/maintenance components.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels5 records

Core offering

Limbus AI develops and sells Limbus Contour, a deep learning-based auto-segmentation software for radiation therapy treatment planning. The software processes CT and MRI images locally on clinical workstations to automatically generate organs-at-risk (OAR) and clinical target volume (CTV) contours, exporting them as DICOM RT-Structure files compatible with any treatment planning system. It runs without cloud connectivity or GPU requirements and includes 260+ clinically validated anatomical structures ready for immediate clinical use.

Product overview

Limbus AI provides a unified product portfolio for AI-driven automatic contouring in radiation therapy. The core offering is Limbus Contour, an on-premises auto-segmentation solution that processes medical images locally to generate contours for radiotherapy planning. In 2024, following acquisition by Radformation, Limbus Contour was unified with Radformation's AutoContour into AutoContour v2.7 — a single AI-driven contouring platform that delivers fast, consistent, and scalable contouring across imaging modalities. The product features an extensive library of 260+ clinically validated anatomical structures (organs at risk and clinical target volumes) and operates entirely on local workstations with no cloud data transfer required.

Differentiator

Problem solved

Functional benefit

Products and services

• Limbus Contour Automatic contouring software for radiation therapy that generates clinical-grade contours using deep learning segmentation. Processes CT and MRI images locally on clinical workstations, exports DICOM RT-Structure files, and integrates with treatment planning systems without requiring cloud connectivity or GPU hardware. Used by radiation oncologists, medical physicists, and dosimetrists in hospitals and cancer centers.
• AutoContour v2.7 Unified AI-driven contouring platform that combines AutoContour and Limbus Contour into a single product. Delivers fast, consistent, and scalable contouring across imaging modalities through zero-click automation or seamless TPS integration, reducing variability and accelerating the path from image to plan. Available to radiation oncology customers following Radformation's acquisition of Limbus AI.

Quantifiable outcome

• 5-10x faster than manual contouring
• +7 more outcomes

Named customers11 records

Segments1 record

Ideal customer profiles1 record

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

AI capability3 records

Feature6 records

Scale indicators2 records

Recent moves6 records

Expansion highlights5 records

Direct peers

• Therapanacea: France-based company providing AI auto-segmentation for radiation oncology workflows, including atlas-free deep-learning contouring across multiple anatomical sites — a close functional match to Limbus Contour.
• RaySearch Laboratories: Swedish developer of radiation therapy treatment planning software (RayStation) and increasingly AI-enabled planning tools. Competes for the same RT department budgets and increasingly bundles auto-segmentation capabilities.
• MVision AI: Finland-based AI auto-contouring vendor specifically focused on radiation therapy planning. Ships deep-learning-based OAR and target segmentation directly competing with Limbus Contour for the same radiation oncology customers.
• Mirada Medical: UK-headquartered medical imaging AI company with a strong installed base in radiation oncology, offering AI-driven auto-contouring and treatment planning integrations that directly overlap with Limbus's RT contouring niche.

Emerging players

• MIM Software: US medical imaging AI vendor with radiation oncology and contouring capabilities (MIM Assistant, MIM Symphony). Smaller than the TPS incumbents but well established in nuclear medicine and RT segmentation workflows.

Broad incumbents

• Varian (a Siemens Healthineers company): Largest radiation therapy systems vendor globally; ships AI contouring as part of Ethos adaptive RT and Eclipse TPS. Represents the most direct bundling threat to Limbus's standalone positioning.
• Siemens Healthineers (AI-Rad Companion): Through AI-Rad Companion, Siemens offers AI-driven organ and contour segmentation for CT and MR imaging; competes indirectly by extending imaging-vendor AI into radiation therapy workflows.
• Brainlab: Sells radiation oncology planning and image-guided therapy software with AI-driven auto-contouring modules; an established incumbent that competes for the same hospital procurement budgets.
• Elekta: Major radiation therapy hardware and software vendor with a growing portfolio of AI-assisted planning and contouring tools integrated into its treatment planning ecosystem.

Others

• Radformation: Acquired Limbus AI in April 2024 and now incorporates Limbus Contour into its AutoContour v2.7 platform. Included as a peer/adjoining platform given the now-overlapping product portfolio and shared radiation oncology customer base.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights7 records

Customer concentration

• Xx.com/limbusai
• LinkedInlinkedin.com/company/limbus-ai

Revenue estimate

Valuation estimate

Number of profiles

Profiles2 records

Funding overview

Funding rounds1 record

Investors1 record

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 Limbus AI