Is that even legal? What happens if my landlord accidentally charges me 10x rent this month and refuse to correct it even after I ask? That's just straight up stealing. I feel like at a minimum I'm getting my money back one way or another, and they are likely to face consequences for theft.

But, no need to set a precedent: I'm quite confident that a US court would refund a person or company that overpaid due to a bug in Antropic's billing.

This is not just one bug, though; it’s a bug that takes money that ain’t theirs to take.