Earlier quoted context omitted.
I read this often, and I guess it could be true, but those kinds of transaction would presumably go through DNM / forums like BF and the like. Which means crypto, and full anonymity. So either the buyer trusts the seller to deliver, or the seller trusts the buyer to pay. And once you reveal the particulars of a flaw, nothing prevents the buyer from running away (this actually also occurs regularly on legal, genuine b…
I don't think you know anything about how these industries work and should probably read some of the published books about them, like "This Is How They Tell Me The World Ends", instead of speculating in a way that will mislead people. Most purchasers of browser exploits are nation-state groups ("gray market") who are heavily incentivized not to screw the seller and would just wire some money directly, not black marke…
Say you're in the US. I'm sure there are some CIA teams or whatever making use of Chromium exploits "off the record", but for any official business the government would just put pressure on Google directly to get what they want. So any project making use of your zero-day would be so secret that it'd be virtually impossible for you to even get in contact with anybody interested to buy it. Sure they might not try to "screw you", but it's sort of like going to the CIA and saying, "Hey would you be interested in buying this cache of illegal guns? Perhaps you could use it to arm Cuban rebels". What do you think they would respond to that?