Originally Posted by Poseidon
Basically what Ink said. And yes, the APHA now requires at least one parent be APHA registered. However, I do believe that if that parent is AQHA/APHA, the foal can also be double registered if the other parent is AQHA.
Yes, since if one parent is AQHA/APHA (double registered) and the other parent is AQHA, this meets the QHxQH requirement to be registered in the AQHA and also meets the parentage requirement of the APHA as a QHxPaint.
The easiest way to think of it is that an AQHA/APHA double registered horse is like having 2 horses from a breeding/registration perspective. The AQHA sees your horse as a QH, and the APHA sees your horse as a Paint.