Updated June 2014
This CSR discusses advertisements in books mailed at Media Mail prices.
Domestic Mail Manual (DMM) 273.3.1* prescribes, in part, that books to be eligible for mailing at Media Mail prices, may contain no advertising matter other than incidental announcements of books.
The publications which are advertised in such books do not have to be eligible for mailing at Media Mail prices. However, they must be books. There may not be advertising for catalogs, calendars, checkbooks, or other miscellaneous printed materials in the books being mailed at Media Mail prices.
*See also DMM 173.4.