The Jargon File (version 4.4.7, 29 Dec 2003):

Usenet Death Penalty


    [Usenet] A sanction against sites that habitually spew Usenet spam. This
    can be either passive or active. A passive UDP refers to the dropping of
    all postings by a particular domain so as to inhibit propagation. An active
    UDP refers to third-party cancellation of all postings by the UDPed domain.
    A partial UDP is one which applies only to certain newsgroups or
    hierarchies in Usenet. Compare Internet Death Penalty, with which this
    term is sometimes confused.