Former Hollywood bodyguard William Castleberry claimed to be the owner of the incendiary home video, with the film set to be offered for sale in a public auction.
It was among a number of possessions of Castleberry's which were seized from his home by the Tulane County Sheriff's Office to cover a court judgement debt against him to the tune of $200,000 (£120,000).
Castleberry had previously said that he would keep the film a secret out of respect for Monroe's ex-husband, the baseball legend Joe DiMaggio, who is a friend of his.
The items, including the 8mm tape, were then to be auctioned to the public to settle the debt.
“It’s real. I had it for years and I never released it out of respect for Joe DiMaggio… I’m just sick about it and I’m desperately trying to raise money to get it back,” he told RadarOnline.
“They demanded a $90,000 payment I couldn’t afford and that is when the sheriff came in and seized the sex tape and all of my other memorabilia I have been collecting my entire life.”
A lawyer working for those seeking payment of the debt confirmed that there was an 8mm film among the items seized, adding at least some credence to Castleberry's story.
“I was able to locate a 8mm film in a canister at the house, which was turned over to [authorities],” said Ryan Sullivan.
“I have no idea what is on the tape, it could be what Mr. Castleberry says, or it could be a Disney cartoon. The only way anyone will ever know is if they buy it and view it.”
However, according to TMZ the debt has now been paid, and the auction has been cancelled.
And in a mysterious twist which might excite those of a conspiratorial bent, TMZ claims 'Castleberry's attorneys tell us they have no idea who made the payment'.
Rumours of impropriety between the late film starlet and the Kennedy brothers have been circulating for decades now, and this particular piece of the puzzle looks like it may not see the light of day after all.