Comment by x0x0

Another way these companies get data is they have credits. It costs a credit for a salesperson to enrich the data of someone they're trying to contact. There are 2 ways to gain credits: 1 - cash; 2 - the salesperson installs a plugin in their inbox and it scrapes all contact info in the inbox.

ZoomInfo is the most aggressive about this.

re apollo: inbox scraping is what they're describing here [1]

> Apollo does leverage its large network of over 2 million contributors to improve the scope and accuracy of its database of business contact information and run verification checks that result in a better user experience for its entire customer base. Most of the data we collect from our Apollo users simply forms part of our verification system to check and confirm existing information in the Apollo database.

[1] https://knowledge.apollo.io/hc/en-us/articles/20727684184589...