Blockchain Analysis Firms Use Honeypots, including logging IPs on blockchain explorer sites https://darknetlive.com/post/ciphertrace-uses-honeypots-to-investigate-crypto-wallets/
Correction: Monopoly Market was not one of the largest, I misinterpreted my research data. It was however the longest standing western cryptomarket.
My source insisted upon remaining anonymous but provided irrefutable proof and confirmed their identity using PGP.
We monitor the darknet (Tor hidden services) for interesting news.