QUESTION: Can you apply for a design patent for a product after the utility patent expires on lifetime term? Was wondering if a design patent was possible if the original utility patent had lifetime expired.
ANSWER: Mostly likely, no.
If all of the features in the design patent are shown in the utility patent, then your design patent would not be new. Likewise, if the features in the design patent are mostly shown in the utility patent, then your design patent might likely be considered as obvious.
The main challenge here is that the utility patent already issued.