How does Clearbit Reveal figure out my company?

Question

Clearbit Reveal (https://clearbit.com/reveal) uncovers the companies behind anonymous website visits. They even correctly identify my company when I visit them from my home desktop. How do they get this information?They say their algorithm works to identify and validate matches, based on Clearbit's processing and application of machine learning to hundreds of millions of new data points each month, along with multiple signals from traffic patterns, geolocation, manual QA and more. (https://clearbit.com/blog/ip-intelligence-for-remote-work). I really struggle to come up with what these data points are.Anyone else have any ideas?

soheil · Accepted Answer

Most likely they get IP addresses from vendors that partner with popular tools like Saleforce and the like. I wouldn't be surprised if Google or Facebook log and sell/give away/leak the IP address linked to a logged in user's email to a third party vendor or ad network. There are also numeric Chrome extensions or other tools that once integrated with a client's browser could track their email and IP address. Once you have a known email/IP address pair it's simple to associate it with a company.