Amazon's stake in Anthropic is proving to be a massive boon to the world's largest online retailer.In its latest quarterly earnings report, Amazon reported non-operating pre-tax other income of $53.4 billion, "primarily from our investment in Anthropic."According to previous financial filings, Amazon has invested $13 billion in Anthropic with the potential for up to $20 billion more. In June, Anthropic announced that it confidentially filed for an initial public offering, taking the first step toward a high ...