Shill

A shill, also called a plant or a stooge, is a person who publicly helps or gives credibility to a person or organization without disclosing that they have a close relationship with the person or organization. Shills can carry out their operations in the areas of media, journalism, marketing, confidence games, or other business areas. A shill may also act to discredit opponents or critics of the person or organization in which they have a vested interest through character assassination or other means.

In most uses, shill refers to someone who purposely gives onlookers, participants or "marks" the impression of an enthusiastic customer independent of the seller, marketer or con artist, for whom they are secretly working. The person or group in league with the shill relies on crowd psychology to encourage other onlookers or audience members to do business with the seller or accept the ideas they are promoting. Shills may be employed by salespeople and professional marketing campaigns. Plant and stooge more commonly refer to a person who is secretly in league with another person or outside organization while pretending to be neutral or a part of the organization in which they are planted, such as a magician's audience, a political party, or an intelligence organization (see double agent).

Shilling is illegal in many circumstances and in many jurisdictions because of the potential for fraud and damage; however, if a shill does not place uninformed parties at a risk of loss, but merely generates "buzz," the shill's actions may be legal. For example, a person planted in an audience to laugh and applaud when desired (see claque), or to participate in on-stage activities as a "random member of the audience," is a type of legal shill.Shill can also be used pejoratively to describe a critic who appears either all-too-eager to heap glowing praise upon mediocre offerings, or who acts as an apologist for glaring flaws.

The origin of the term "shill" is uncertain; it may be an abbreviation of "shillaber." The word originally denoted a carnival worker who pretended to be a member of the audience in an attempt to elicit interest in an attraction. Some sources trace the usage back to 1914.

In online discussion media, satisfied consumers or "innocent" parties may express specific opinions in order to further the interests of an organization in which they have an interest, such as a commercial vendor or special interest group. In academia, this is called opinion spamming.Web sites can also be set up for the same purpose. For example, an employee of a company that produces a specific product might praise the product anonymously in a discussion forum or group in order to generate interest in that product, service, or group. In addition, some shills use "sock puppetry", where they sign on as one user soliciting recommendations for a specific product or service. They then sign on as a different user pretending to be a satisfied customer of a specific company.

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