Glean is definitely not the first company to do this, but it's worth pointing out that the company's $300 million milestone cannot be fully described as traditional ARR, because a consumption model by definition doesn't have a strictly recurring component.
This disclosure is important and rare: the journalist explicitly flags that Glean's '$300M' headline is annualized run rate, not ARR. Consumption-based revenue is inherently more volatile than subscription ARR — usage can contract sharply in downturns. At a $7.2B valuation, the quality of the revenue stream matters as much as its size.