What is a bonded mail house?

What is a bonded mail house?
it is a company that provides bulk mailing services. What makes then special is that they have a fiduciary responsibility to protect the mailing list.For example, if you want to send a mailing to all the readers of XYZ Magazine, you may rent their subscription list. Now, of course, they don't want to release control of that list and don't want YOU to have that information directly, as you may choose to use it repeately or for other purposes.In comes the bonded mail house... they get the list from the magazine, and your mail pieces, and they address and mail the campaign. The data is safe, and you get your marketing to the readers of the magazine.