Animals rights group PETA has lost a legal bid for a monkey to own copyright to selfies it took, in a case the organisation says exposes "the hypocrisy of those who exploit animals".

In September last year, PETA (People for the Ethical Treatment of Animals) filed a lawsuit asking the US federal court in San Francisco to declare male crested macaque Naruto the author and owner of the famous photographs he took of himself.

At the time Naruto was living freely in a group in Indonesia. He picked up a tourist's unattended camera and began taking photographs of the forest floor, some of other maraques and several of himself.

On Wednesday, a federal judge in San Francisco ruled the monkey could not be declared the copyright owner of the photos.

Jeff Kerr, general counsel for PETA US, said the organisation would continue fighting for the monkey's rights.

"Despite this setback, legal history was made today because we argued to a federal court why Naruto should be the owner of the copyright rather than been seen as a piece of property himself," he told the ABC.

"This case is also exposing the hypocrisy of those who exploit animals for their own gain."

According to PETA, the US Copyright Act grants copyright ownership of a "selfie" to the "author" of the photograph, and there is nothing in the law limiting such ownership on the basis of species.

PETA said on its website before the case: "As 'next friend' to Naruto, we're seeking the court's permission to manage the copyright of the photos, license them for commercial use, and use 100 per cent of the proceeds to benefit Naruto and his community, whose habitat and very existence are under threat."