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June 1 (Reuters) - AI giant Anthropic said on Monday it has confidentially filed for a U.S. initial public offering, teeing up what could become the watershed moment for Wall Street's AI frenzy.

The move sets up a high-stakes test of whether investor appetite for the AI revolution that has reshaped white-collar work around the world can match the sky-high expectations surrounding the booming sector.

Anthropic did not disclose the size or terms of the offering. It last raised $65 billion at a post-money valuation of $965 billion in late May, putting it ahead of rival OpenAI.