If the A.I. was engineered by engineers who work for a Corporation, then the ownership belongs to the Corporation. That is how most contracts work. Some Corporations, if you read the fine print of the contract, can even make the engineers liable for any damages caused by their own innovation even though they do not own the patent and can’t receive royalties. It is a legal loophole which stipulates that in the instance an innovation causes mass damage and the lawsuits start flooding in, then the engineer is considered at that point an independent contractor.
If the A.I. was engineered by engineers who are self-employed, then the ownership belongs to them.
If the A.I. innovated on its own, then the question is if the A.I. is considered the property of the Corp or the property of self-employed engineers, or is it considered independent. I would say that until the law changes, the A.I. would be considered a property of the Corp.
Animals, for example are considered property by law. If any animal were to evolve into something that can innovate, until the law states otherwise, the animal is still the property of its owner, thus the owner owns the innovation.