barrier of entry with the costs of research & development and large-scale production, and fewer manufacturers entered the market during this period. This new line of consoles had its breakthrough moment when Atari obtained a license from Taito to create the Atari VCS version of the arcade hit Space Invaders, which was released in 1980. Space Invaders quadrupled sales of the Atari VCS, making it the first "killer app" in the video game industry, and the first video game to sell over one million copies and eventually sold over 2.5 million by 1981. Atari's consumer sales almost doubled from $119 million to nearly $204 million in 1980 and then exploded to over $841 million in 1981, while sales across the entire video game industry in the United States rose from $185.7 million in 1979 to just over $1 billion in 1981. Through a combination of conversions of its own arcade games like Missile Command and Asteroids and licensed conversions like Defender, Atari took a commanding lead in the industry, with an estimated 65% market share of the worldwide industry by dollar volume by 1981. Mattel settled into second place with roughly 15%-20% of the market, while Magnavox ran a distant third, and Fairchild exited the market entirely in 1979. Another critical development during this period was the emergence of third-party developers. Atari management did not appreciate the special talent required to design and program a game and treated them like typical software engineers of the period, who were not generally credited for their work or given royalties; this led to Warren Robinett secretly programming his name in one of the earliest Easter eggs into his game Adventure. Atari's policies drove four of the company's programmers, David Crane, Larry Kaplan, Alan Miller, and Bob Whitehead, to resign and form their own company Activision in 1979, using their knowledge of developing for the Atari VCS to make and publish their own games. Atari sued to stop Activision's activities, but the companies settled out of court, with Activision agreeing to pay a portion of their game sales as a license fee to Atari. Another group of Atari and Mattel developers left and formed Imagic in 1981, following Activision's model. Atari's dominance of the market was challenged by Coleco's ColecoVision in 1982. As Space Invaders had done for the Atari VCS, Coleco developed a licensed version of Nintendo's arcade hit Donkey Kong as a