Microsoft Entertainment Pack rarity linked to Tetris licensing

Former Microsoft engineer Raymond Chen has shared details regarding the rarity of certain early editions of the Microsoft Entertainment Pack for Windows. Released in 1990 for Windows 3.x, the software bundle contains several games, including the classic Tetris.

According to Chen, the initial production run of the packaging was printed without any mention of Tetris because licensing negotiations for the game were still ongoing at the time. To mitigate the risk of the deal failing, Microsoft opted to use stickers to indicate the inclusion of Tetris on the first batch of boxes.

Once the rights were officially secured, subsequent production runs featured the Tetris branding as part of the permanent printed design rather than as an adhesive sticker. These original versions with the Tetris stickers are considered extremely rare collector's items.