Under The Breach explains:
A group of sophisticated hackers team up to sell the data of computers they managed to infect.
The site began operating around the beginning of 2019 and only let users with an invitation code to join (it maintains this exclusivity until today).
To find a person who has invitation codes is not that difficult because each member that spends $20 on the site gets to generate an invitation code.
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Basically, the site has an insane amount of 230,000 infected computers you can buy the logs from. 20,000 of which are from the USA.
The site operates just like any online clothes shop would only a lot more sinister.
Read more on Medium.