The music legend, who died unexpectedly in 2009 at age 50, had purchased the Academy award in 1999, paying USD 1.54 million in a Sotheby's auction, said The Hollywood Reporter.
The 1940 Oscar was awarded before there were rules against selling them.
"The estate does not know where the 'Gone With the Wind' statuette is. We would like to have that Oscar because it belongs to Michael's children. I'm hopeful it will turn up at some point," Jackson's attorney Howard Weitzman said.
Jackson is presumed to have kept the Oscar at either his Neverland estate near Ojai, California, or at the LA home where he was living when he died. But the Oscar was not found among his belongings, according to the estate.