A "Pump and Dump" scheme is an illegal white-collar racket commonly employed by organized crime. Phones are set up (usually in a rented office or warehouse) and naive potential investors are called. A stock is over-hyped and its financial potential is made to look much better than it really is. When enough people buy the stock the price goes up. This is the "Pump" part of the scheme. What the investors don't know is that the stock is only a husk and that the people making the advertisement calls are really the stock owners themselves. This is considered illegal. The stock is then "Dumped" or sold and the owners make a profit. This crime was committed by Christopher Moltisanti in the episode "Guy Walks into a Psychiatrist's Office...". In the episode, Chris pushes the faulty stock known as "Webistecs".