Amazon has invested an additional $2.75 billion in AI startup Anthropic.

The deal marks the second round of funding provided by the cloud and eCommerce giant under a previously agreed plan to invest up to $4bn in the startup.

In September 2023, Amazon made an initial investment of $1.25bn for a minority stake in the company. Amazon is also Anthropic’s primary cloud provider for mission-critical workloads, including safety research and future foundation model development.

Anthropic was founded in 2021 by OpenAI's former vice president of research, Dario Amodei, and a number of former OpenAI staffers. Its AI model Claude has been trained on constitutional AI, a system that uses a “set of principles to make judgments about outputs,” which helps Claude to “avoid toxic or discriminatory outputs,” such as helping a human engage in illegal or unethical activities.

To date, Anthropic has raised a total of $7.6bn in funding over 10 rounds, and in December 2023 it was reported that the startup was in talks to embark on another funding round to raise $750 million and seek a valuation of $18.4bn.

In a statement, Amazon said Anthropic will use AWS Trainium and Inferentia chips to build, train, and deploy its future models, with the startup also making a “long-term commitment” to provide AWS customers with access to future generations of its foundation models on Amazon Bedrock.

“We have a notable history with Anthropic, together helping organizations of all sizes around the world to deploy advanced generative artificial intelligence applications across their organizations,” said Dr. Swami Sivasubramanian, vice president of data and AI at AWS.

He added: “Generative AI is poised to be the most transformational technology of our time, and we believe our strategic collaboration with Anthropic will further improve our customers’ experiences, and look forward to what’s next.”

Amazon is not the only cloud company to have made a significant investment in Anthropic. In late 2022, Google acquired a 10 percent stake in Anthropic for $300 million, investing an additional $500 million in October 2023 and pledging to provide another $1.5bn over an unknown timeline.

Earlier this week it was reported that bankrupt cryptocurrency exchange FTX had struck a deal to sell $800 million worth of shares in Anthropic to a consortium of buyers, including ATIC Third International Investment Company and Jane Street Global Trading.