The Academy of Motion Picture Arts and Sciences confirmed it was preparing to send the Oscar Ledger won last month for his iconic performance as The Joker in The Dark Knight to Matilda's mother, actress Michelle Williams, who lives in Brooklyn, New York, with Matilda.

The announcement solved the mystery of who would look after the Oscar until Matilda turned 18.

Under Academy rules the deceased actor's next of kin takes ownership. With Matilda aged just three, the Academy ruled the Oscar would have to be held until her 18th birthday.

On Oscar night Ledger's parents, Kim and Sally and sister Kate, accepted the award on stage and at a backstage media conference admitted they were not sure who would take care of the statuette until Matilda became an adult.

Kim Ledger raised the possibility it would go back to Australia.

Academy spokesperson Leslie Unger, however, confirmed Williams, who lives in Brooklyn, New York, with Matilda would receive it.

"We expect a representative of the Ledger estate to bring the statuette in tomorrow so that the engraved plate can be affixed," Unger told the Los Angeles Times newspaper. "Soon after that, we expect the statuette to be delivered to Michelle Williams."

The LA Times also reported his Screen Actors Guild Award is yet to be claimed because no-one has completed the necessary paperwork to collect it. Ledger's Golden Globe was sent to his New York-based publicist Mara Buxbaum, who also represents Williams.

Perth-born Ledger died aged 28 from an accidental prescription drug overdose on January 22 last year. -- AAP