What is run-rate revenue and how is it different than revenue (classic)?
Run-rate is taking a recent measurement and multiplying it out so it will span a year. Basically, it assumes they keep all of their current contracts, and don't gain any new ones.
Forward-looking revenue is an estimate of what the integral will be from now to a year from now.
For a growing company, run rate is between past revenue and estimates of future revenue.
Forward-looking revenue estimates are often made up from whole cloth so are highly untrustworthy. But a run-rate is saying "we've already been making this much money, we just need to maintain where we are and that's how much we'll bring in". Backward-looking revenue for something like Anthropic is meaningless because almost all of their customer base is recently acquired - they're growing like crazy, not 20% per year.