With Anthropic announcing its US IPO, attention is turning to the tech giants that have poured billions of dollars into the AI company behind Claude.The startup has filed to list its shares on the Nasdaq under the ticker symbol ANT, with Goldman Sachs and Morgan Stanley leading the offering.According to Reuters, Amazon and Google are among Anthropic’s major financial backers, investing billions of dollars in the startup while also providing the cloud computing infrastructure needed to develop and run its AI models.The company’s IPO filing highlights how closely Anthropic’s growth is tied to these technology giants, which are also competitors in the AI market.Amazon has invested $8 billion in Anthropic previously and announced another $5 billion investment, with the option to invest up to an additional $20 billion in the future, according to Anthropic’s April 2026 announcement.If the full additional amount is invested, Amazon’s total investment would reach $33 billion. The companies are also expanding their infrastructure partnership, with Anthropic committing to spend more than $100 billion on AWS technologies over the next decade and securing up to five gigawatts of computing capacity.Google is another major investor and computing partner. Reuters reported that Anthropic plans to spend at least $111.1 billion with Google on infrastructure over the next seven to 10 years.Anthropic has also partnered with Google and chip designer Broadcom to expand access to Google’s tensor processing units (TPUs), which are used to train and run AI models.Nvidia’s involvement includes both a potential IPO investment and an earlier strategic partnership. Reuters reported in September that Nvidia was considering investing up to $10 billion in Anthropic’s IPO, although the discussions could change.Separately, Nvidia announced plans to invest up to $10 billion in Anthropic in November 2025 as part of a partnership linked to Anthropic’s commitment to purchase $30 billion of Microsoft Azure computing capacity powered by Nvidia chips.Microsoft is another key infrastructure partner, with Anthropic committing to spend $31.4 billion on Microsoft infrastructure between November 2026 and May 2033, according to Reuters.Chip designer Broadcom, meanwhile, is linked to around $161.2 billion in equipment lease obligations and has agreed to lend Anthropic up to $42 billion for infrastructure spending.Anthropic’s May 2026 Series H funding round raised $65 billion at a post-money valuation of $965 billion, with investors including Sequoia Capital, GIC, Coatue, Blackstone, Fidelity and Temasek.Reuters reported that Anthropic expects to spend at least $518 billion over a decade with six partners to build AI infrastructure, with about 80 per cent of the commitments non-cancellable or payable regardless of usage.The company says its funding will support more capable AI systems, safety research and products such as Claude Code and Cowork.