Provide inaccurate information regarding home
telephone numbers (e.g., fax machine, the business' own number,
etc.)
This includes businesses you trust because they may be
including the phone number on someone else's form.
It appears that they are getting their data from four sources:
"war dialing" (dialing every number
in an exchange), or dialing every number listed as valid
dialing from telephone subscriber lists (listed
phone numbers)
dialing from information obtained from businesses and credit
agencies. This is where giving the wrong information helps!
"spam lists" of Known Good Numbers (obtained from previous successful connections)
The callers using information obtained from businesses are the
most persistent because they paid for ostensively valid
information, from targeted lists.
Inaccurate information is better than no information because the
information gatherers will sometimes attempt to fill in blanks in
their lists. If you have a properly listed phone number, your
home number will be inserted. If the information is simply
wrong, the people who collect these numbers generally never find
out, and so it gets sold that way.
If you are concerned about someone at the business getting in
touch with you, provide your work phone in addition to the number
you gave as your home phone, or provide your home number as your
"work" phone. (Add a bogus
"extension number" when you list your home number as a
"work number", e.g., 202-456-1414 x12.)
Look for original sources of your personal data.
Typically these are insurance companies, utilities and
creditors. If you find some original source has your number in
their database, update their information with inaccurate
information. "Inaccurate information" is
the most efficient way to make your number "disappear"
from their lists. Typically you'll get a request to confirm your
phone number. If you get what they refer to as a "courtesy
call", call back later and "update" their
information.
Give bad information on surveys.
Don't answer "hello" more than once.
(when convenient) Keep them on the line as long as possible.
Don't list your full address in your telephone listing.
Check your listing with directory assistance before
the book publishes.
Try to avoid calling 800 numbers from home phone numbers,
especially during evening hours. (caller ID
blocking doesn't work with 800 numbers.)
If you like what they're offering, buy it from someone else.
The FRCA (US) provides for an "opt out"
procedure for the purpose of blocking credit reporting agencies
from releasing marketing data.
1-888-567-8688 . This
"opt out" procedure must be renewed every
two years, so it makes sense to call about once a year.