Here are the pertinent details from Tanner's post:
"Whenever you fill out a change of address form with the United States Postal Service, the USPS adds your new details into a database of 160 million previous address changes over the past four years. The USPS has deals with data brokers to sell this data to anyone who pays, provided they have your old address. That means data firms cannot buy the address of Leroy Jones in Cincinnati, but can obtain his new address if they know where he used to live, which they usually do anyway."
The tiny print on a change of address form says the USPS won't disclose your address to anyone, with a few exceptions, one being "to mailers, if already in possession of your name and old mailing address, as an address correction service."
This is a huge pain for people who'd rather not get advertisements in the mail, but it turns out that there's a small loophole to help you get around this.
When you fill out a change of address form on the USPS website you can indicate it to be a temporary change, which leaves it intact for six months. After that, it can be renewed for another six months. Because you've told the USPS that this is a short-lived change, they do not sell this information to advertisers.
Of course advertisers can still get your new address from updated magazine subscriptions, credit card details, and phone number changes. So it's an uphill battle, to be sure.
