The poison pill was invented by mergers and acquisitions lawyer Martin Lipton of Wachtell, Lipton, Rosen & Katz in 1982, as a response to tender-based hostile takeovers. Poison pills became popular during the early 1980s in response to the wave of takeovers by corporate raiders such as T. Boone Pickens and Carl Icahn. The term "poison pill" derives its original meaning from a poison pill physically carried by various spies throughout history, a pill which was taken by the spies if they were discovered to eliminate the possibility of being interrogated by an enemy.