07252591 is referenced by 163 patents and cites 307 patents.

A gaming device is provided including a set of symbols on a plurality of reels and a symbol stack that includes an initially displayed symbol and at least one initially hidden symbol. In one embodiment, the hidden symbols are stacked beneath the displayed symbol. The initially displayed symbol may be removed to reveal an initially hidden symbol so that one or more different sets of visible symbols appears on the display device.

Title
Gaming device having symbol stacks
Application Number
10/209704
Publication Number
7252591 (B2)
Application Date
July 31, 2002
Publication Date
August 7, 2007
Inventor
Shawn M Van Asdale
Reno
NV, US
Agent
Bell Boyd & Lloyd
Assignee
IGT
NV, US
IPC
A63F 9/24
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