There are several possible ways you may end up being on a telemarketing list including:
- Having a listed telephone number
- ICANN Domain Registration Info that includes your number
- Listing your number on personal checks
- Updating account information at a company you use for some sort of service that re-sells your information.
- 800 number that records incoming calls by Automatic Number Identification (ANI)
- Credit card information services, Equifax, TransUnion, etc.
- Ordering products from any company, by mail, catalogue, etc.
Lists of numbers are often sold or shared between companies. All it takes is one company to sell your number, for it to spread to hundreds of different telemarketing lists. It is nearly impossible to read privacy policies for every company you do business with, and as a result is a good idea to register on the state and federal do not call lists.