Amazon has invested an additional $4 billion in Anthropic, the AI startup behind the chatbot Claude, doubling its total funding to $8 billion. The latest funding, reported by Reuters, will be disbursed in phases, beginning with $1.3 billion.

Anthropic, which remains independent despite Amazon’s backing, is leveraging Amazon’s AI chips—Trainium and Inferentia—to train its advanced AI models.

The startup is also collaborating with Amazon’s Annapurna Labs to develop new processors as part of Amazon’s efforts to compete with tech giants like Microsoft and Google in the AI sector.

Amazon Web Services (AWS) has become Anthropic’s primary cloud provider, distributing the startup’s AI models to clients. This partnership will bolster Anthropic’s revenue while advancing Amazon’s AI offerings.

Meanwhile, Anthropic is exploring additional funding opportunities amid a surge in AI investments, including OpenAI’s recent $6.6 billion round. The startup, co-founded by former OpenAI executives Dario and Daniela Amodei, has previously secured $2 billion in funding commitments from Alphabet, Google’s parent company, and uses Google Cloud for some of its operations.