A film using the unseen video images is already being lined up by the promoter of his O2 Arena shows, AEG. They expect to earn hundreds of millions once it has been sold around the world, and more from an accompanying soundtrack.
Though AEG shot the footage, Michael's estate owns the rights to his name and image. Company boss Randy Phillips said the children, Prince Michael, 12, 11-year-old Paris and seven-year-old Blanket, will get "the lion's share" of royalties.
Hollywood insiders say the feature-length movie, which will be made up of some 80 hours of Michael's rehearsals at the LA Staples Centre, could be in cinemas in time for Christmas.
AEG are also selling the TV rights to a tribute concert, due to take place on August 29 - what would have been Michael's 51st birthday. Jermaine Jackson has confirmed he'll team up with remaining Jackson 5 members Tito, Marlon and Jackie to sing at the concert, along with a lineup of other stars.
Justin Timberlake and Janet Jackson will also perform at the event, which will be repeated again the following night. And Jermaine says the family want to stage a further string of shows in the UK as a further tribute to the star, who died last month.
"I want to see something where people can really feel his love and sing his songs," says Jermaine. "The brothers will do something, Janet will do something. They're speaking to Usher, Justin Timberlake, Mariah Carey, Lionel Richie, Stevie Wonder. We have to keep his legacy alive."