Several startups fill this identity-knowledge gap for law enforcement targeting criminals or investors analyzing successful investment strategies. These startups identify address owners by scraping websites and using analytics to associate addresses with multiple user attributes, like social network profiles, geolocations, mobile numbers and email addresses. They collect data from darknets, social networks and open-source forums, and purchase data from proprietary sources when possible.
Source: https://www.coindesk.com/layer2/privacyweek/2022/01/26/criminals-still-find-it-easier-to-hide-in-fiat-than-crypto/