In an article entitled Dissing the competition through dirty tricks! Arthur Weiss cites an article that illustrates how a campaign of dirty tricks might unfold. The cited Times Online article is very educational.
More recently, the Canadian insurer, Fairfax, was the target of a campaign of malicious disinformation from a group of Wall Street Hedge Fund managers. The company is now suing them for $6 billion – claiming that their aim was to manipulate the market by creating uncertainty about the company and its future. These include a variety of dirty tricks – false emails and letters, espionage attempts and more.
The main actor accused of conducting the dirty tricks campaign was Spyro Contogouris. Googling “spyro contogouris” brings up more than you might want to know. Especially the claim that Contogouris was working for the FBI.