As far as I know pinto horses were mostly bred in the USA. I would definitely consider it american, I have no idea why you would say it's spanish. It's definitely not a spanish breed.
Pinto is not a spanish breed. (Technically we probably shouldn't even call it a breed, it's a colour.) However the point is that they were mostly bred in the USA. The largest number of pinto horses are in America. There is no logical reason to call them spanish horses. I don't understand why someone would give that answer.
The Lipizzan however were developed by a the Habsburgs. And they used spanish horses, so yeah, the Lipizzan IS a spanish horse breed.
