Resident Tetris historian here, doing a bit of research on the "origin" of Tetris' very specific birth-date. Since there's been a lot of misinformation floating around the web on this topic over the past few years, I thought I'd share the facts I've been able to find, and ask for anyone to fill in any details I might have missed: Prior to 2009, the general consensus was that Tetris was originally created sometime in 1985. (Some such as tsr's "The Tetris Saga" say more precisely June 1985. Anyone know where this date comes from?) Sheff's 1993 book "Game Over" reports November 1985 as the Tetris-related date: "In a computer-game competition held in Zelenodolsk, in November 1985, 'Tetris' took second prize" (301). The "Tetris 0" copyright registration (PAu001214036 / 1989-05-22) lists a "Date of creation" as "1985." In a 1997 press release announcing the official launch of Tetris.com, Blue Planet Software wrote that Tetris was "created in 1985 by Russian scientist Alexey Pajitnov." In its original form, Vadim Gerasimov's webpage "Tetris Story" wrote that "Tetris is a popular game developed in 1985-86 by Alexey Pajitnov (Pazhitnov), Dmitry Pavlovsky, and me." (On June 2, 2009, this would be changed to read "1984-1986"; see the diff between the first c.2006 draft and the latest version.) On June 2, 2009, with a budget of $250,000 from Blue Planet Software, the PR firm Grayling Connecting Point kicked off its "Tetris' 25th Anniversary" (web) media campaign to raise awareness of the Tetris brand. June 2 was a Tuesday, the first day of the Electronic Entertainment Expo (E3). June 2, 2009 is the earliest date I have been able to find where the year 1984 and the date June 6 have ever been mentioned by anyone in connection to Tetris. (Anyone have any other references?) June 6, 2009 was the Saturday after E3 that year, the perfect day to host a big celebration event and maximize PR for an electronic entertainment brand. So my working theory based on the above is that the June 6, 1984 date was fabricated by Grayling as part of its Tetris media campaign package for its client Blue Planet Software, and that they back-dated the birth-date because celebrating a "24th anniversary" would be too lame for a big media event. It seems much more reasonable that "Tetris" in its distributed, named form (as opposed to the "Genetic Engineering" prototypes Pajitnov may have had earlier) was created some time around mid-1985. Anyone have any other thoughts or info?