The appeal brief was filed at the northern district of California and the appeals court will now decide whether or not to uphold the earlier court ruling, Ubergizmo reported on Monday.
In an earlier ruling, a federal judge in San Francisco declined to give a macaque monkey the right to his famous selfie in Indonesia in 2011.
Peta had filed a lawsuit last September asking a US federal court in San Francisco to declare Naruto - a then six-year-old male, free-living crested macaque - the author and owner of the internationally famous monkey selfie photographs that he took himself a few years ago.
The organisation filed the lawsuit against photographer David J Slater and his company, Wildlife Personalities Ltd - both of which claim copyright ownership of the photos that Naruto took.
Naruto is known to field researchers in Sulawesi who have observed and studied him for years as they work in the region.
In 2011 in Indonesia, Slater left an unattended camera on a tripod.
That was tempting for Naruto, a curious male crested black macaque, who took the camera and began taking photographs - some of the forest floor, some of other macaques and several of himself one of which resulted in the now-famous "monkey selfie".
In an earlier statement, Peta said: "The US Copyright Act grants copyright ownership of a 'selfie' to the 'author' of the photograph, and there's nothing in the law limiting such ownership on the basis of species."
"Naruto has been accustomed to cameras throughout his life, saw himself in the reflection of the lens, made the connection between pressing the shutter and the change in his reflection, and posed for the pictures he took," Peta said in a statement.
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