Foundation model vs General-purpose AI model (GPAI)

Why they differ

A foundation model is the research name for the idea; a general-purpose AI model is the legal category in the EU AI Act, with its own tests and duties.

Foundation model

Model architectures

A large model built once on huge amounts of broad data and then reused as the starting point for many different tasks.

Formal

A deep learning model given pretraining on broad data at scale, usually by self-supervised learning, so that it can be adapted - by fine-tuning, prompts or tools - to a wide range of tasks it was not built for.

In plain English

Like a general education that takes years to get, after which a person can learn to be a nurse, a lawyer or a cook in far less time.

In practice

An insurance company's AI lead does not train a model from scratch; she takes a foundation model from a provider and adapts it both to answer customers about their policies and to sum up claim files.

Why it matters

Many products rest on the same few foundation models, so a flaw, bias or weakness in one of them spreads to every system built on top of it.

General-purpose AI model (GPAI)

AI risk & governance

The EU AI Act's name for a broad model that can handle many different tasks and be built into many other AI products.

Formal

Under Art. 3(63) of the EU AI Act, a model of significant generality that can competently perform a wide range of distinct tasks and be built into many other systems; providers owe documentation, a copyright policy and a training-data summary (Art. 53), and more if the model poses risks to society as a whole (Art. 55).

In plain English

Like a company whose engine ends up in cars, boats and generators - the law asks the engine's maker for proper paperwork so every builder further down the line knows what they are fitting.

In practice

A Danish research centre releases a Danish-language model under an open licence; its project lead checks that this spares it the technical documentation, but it must still publish a summary of the training data and a copyright policy.

Why it matters

One model can sit under thousands of products, so since August 2025 the EU has placed duties directly on its maker instead of leaving every product builder to guess at the model's risks.

Shared connections

Open-weight model