The European Patent Office (EPO) has granted Ada Health a patent for its hybrid AI architecture — an ensembling approach that combines the strengths of large language models with clinical precision, explainability, and regulatory standing.
BERLIN — April 13 2026 — Ada Health, a leading clinical AI company that helps people understand their symptoms and navigate care safely and efficiently, today announced that the EPO has granted a patent for Ada’s hybrid clinical AI architecture. The patent recognizes the novelty of Ada’s ensembling approach: a system that combines an LLM with its proprietary probabilistic graphical model to deliver a solution that is more accurate and user-friendly than either approach alone.
AI is now a primary entry point for health questions at scale. But the clinical safety weaknesses of general-purpose LLMs are increasingly well-documented: independent research has identified under-triage of emergencies, errors, and hallucinations. Rather than choosing between the conversational flexibility of modern language models and the clinical rigour that healthcare demands, Ada’s system delivers both.
“LLM providers are discovering that scale and medical safety are not the same. Ada has spent over a decade building the clinical infrastructure that makes AI safe to deploy in healthcare — the validated knowledge base, the regulatory certification, the safeguarding protocols. This patent protects the architecture that brings all of that together with the power of modern language models. It is the clinical layer the industry has been waiting for.”
Daniel Nathrath – Founder and CEO, Ada Health
What the Patent Protects
Ada’s hybrid engine includes an LLM on the front end, which allows users to describe symptoms, medical history, medications, and preferences in their own words, capturing the clinical nuance and contextual detail crucial to pre-diagnosing complex or rare conditions. The system dynamically prompts users with medically relevant follow-up questions constrained to Ada’s validated knowledge base, preventing ungrounded outputs that arise from unconstrained LLM use in clinical settings. This is a structural safeguard built into the architecture. Finally, the patented hybrid model assesses symptoms independently, with the LLM functioning as a second opinion alongside Ada’s expert-curated medical knowledge base. The two models are ensembled: Ada’s reasoning engine acts as a guardrail, while improving relative accuracy by more than 7% and preserving the rigour that medical-grade deployments demand.
The result is a fully white-box, auditable clinical reasoning system. The data insight and explainability of Ada’s outputs, which have been running at population scale since 2016, continues to be a crucial feature for its industry-leading pharma, health systems, and payer partners around the world.
“The engineering challenge is not building a hybrid, it’s making one where clinical rigour and conversational flexibility reinforce each other rather than trade off. Ada’s architecture resolves that by design: the LLM captures what users want to say, Ada’s probabilistic model and ensemble solution determine what it means clinically, and Ada’s reasoning engine is always the decision-maker. That is what makes it safe, explainable, and deployable in regulated environments.”
Graham French – Chief Technology Officer, Ada Health
Following the EPO patent grant, Ada will extend its hybrid approach across its pharma, health systems, and payers partners, where safety and explainability are prerequisites.
About the Patent
The patent (EP4679451B1) covering Ada Health’s hybrid architecture was officially granted by the European Patent Office and went into effect on March 25, 2026, with a priority date of July 12, 2024.
About Ada Health
Ada Health combines clinical expertise and advanced AI to help people and health organizations act on insights earlier. Built by doctors, scientists, and engineers, Ada applies probabilistic reasoning technology to a medical expert-curated knowledge base that transforms real-world data into actionable guidance, empowering individuals to understand their symptoms and helping partners across healthcare and life sciences deliver more timely, personalized care. As a Class IIa medical device under the EU’s Medical Device Regulation (MDR), with over 50 million assessments and 50+ independent peer-reviewed publications, Ada’s assessment is trusted by leading health systems, insurers, and pharmaceutical companies around the world. Learn more at about.ada.com.