Here's another example of that grey area:
If you take a photo with your camera, the copyright belongs to you. But if a monkey takes a selfie with your camera, then what?
Sometime in 2011, a female Celebes crested macaque took a photo of herself with the camera of photographer, David Slater. Slater licensed the photographs that year to a news agency. This led to a series of copyright disputes over who owned the photograph -- the creator (the monkey) of the photograph or the human photographer to whom the equipment belonged.
Even the organization known as PETA (People for the Ethical Treatment of Animals) got involved to try to establish a court precedent that animals could be copyright holders. An article from Vice "I'm a Human Man Being Sued By a Monkey," explains that this case, filed by PETA with the US Ninth Circuit Court, ended in a settlement and (left Slater facing bankruptcy!).
Image: SULAWESI or CRESTED BLACK MACAQUE (Macaca nigra). Sulawesi, Indonesia.
Credit: David J. Slater. Used under fair use for educational purposes.