Academy bosses believe the former eBay.com auction item is the gold man sound engineer Aaron Rochin won for his work on The Deer Hunter in 1979. Rochin returned his Oscar for repair and it was stolen from the Academy's workshop, according to The Hollywood Reporter.
Now, AMPAS officials believe the "rare pre-1950 Academy of Motion Pictures Arts and Sciences OSCAR statue award" James Dunne put up for sale last year (11) is actually the missing accolade.
Dunne allegedly ended the eBay sale prematurely and sold the statuette to another man, named Edgard Francisco, for $25,000 (£15,625).
Academy bosses have contacted Dunne, who claims he acquired the Oscar from an estate sale. Francisco was also contacted, and claims his purchase has been identified as a counterfeit by a collector. He insists he discarded the 'fake' after reaching a compensation deal with Dunne.
But the Academy officials aren't satisfied and now they are suing Dunne and Francisco.
In legal documents obtained by The Hollywood Reporter, AMPAS lawyers state, "If the Statuette was a counterfeit, defendants have infringed the Academy's copyright in the Oscar statuette by selling and distributing a counterfeit statuette. If the statuette was authentic, defendants have committed conversion by asserting dominion over the Academy's property and interfering with the Academy's right to possession of its property."
The Academy bosses are demanding at least $25,000 (£15,600) in damages for the "reasonable value of the converted Statuette" and actual damages or statutory damages of up to $150,000 (£93,750) for wilful copyright infringement.