According to a Scientology website: "A suppressive person is a person who seeks to suppress any betterment activity or group. The suppressive person, also called an antisocial personality, works to upset, continuously undermine, spread bad news and denigrate other people and their activities. While it has sometimes been said that a suppressive person is just anti-Scientology, the fact is they oppose anyone doing better in life."
Scientologists are highly encouraged to "disconnect" from those the Church of Scientology have deemed suppressive persons, or SPs, and may be banned from Church activities if they continue contact. SPs may include friends and family. About 2.5% of the population are considered to be SPs.