"Tens of millions" for controlling stake in NSO is like an order of magnitude less than what I'd imagine in todays environment. Comes off as cheap. Have their capabilities been overplayed? Is selling done under pressure? Are they not actually sitting on big bank and procurement network of valuable 0days?
They only cost a few million dollars to find or just buy and last I checked, a few years ago, there are multiple brokers each with tens in stock.
With that much prevailing stock, you do not run the risk of suddenly not having a supply, so you do not even need to keep a material hoard for yourself. They probably just had like 3-5 at any one time with a in-house team only requiring a few million a year in funding to keep up with the expected churn. If they got more churn than expected, then they buy them retail to keep their product working.
So even if we go with 9 M$ per 0-day (which is a multiple of actual cost), we would only expect them to have like 50 M$ in “assets” and a “procurement network/exploit factory” capable of keeping up with “depreciation” on-average.
Seems pretty reasonable to be under 100 M$. If we went with more reasonable numbers, it would not even be that weird if it was less than 20 M$ for over 50% even at their peak.