ALEXANDRIA, Va., Jan. 28 -- United States Patent no. 12,536,870, issued on Jan. 27, was assigned to IGT (Las Vegas).
"Retaining designated symbols" was invented by Adrian Wotton (Marrickville, Australia).
According to the abstract* released by the U.S. Patent & Trademark Office: "Systems and methods that retain, upon a designated symbol retention event occurring in one play of a game, one or more designated symbols for a then unknown quantity of subsequent plays of the game."
The patent was filed on June 7, 2022, under Application No. 17/834,603.
*For further information, including images, charts and tables, please visit: http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G...