Weights
The specific values stored inside an AI model after training — essentially what it has 'learned.' When a company releases model weights openly, it means anyone can download and run that model on their own hardware, without going through an API. Open-weight models like Meta's LLaMA work this way. Claude's weights are private — Anthropic keeps them on their own servers, which is why you access Claude through Claude.ai or the API rather than running it yourself.
In practice
Claude's weights are the billions of numerical values learned during training that encode everything it knows. When Anthropic releases a new Claude version, they've updated the weights. You can't inspect or change them — they're the proprietary core of the model. Open-weight models like LLaMA release these publicly; Claude's are private.
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