Which of the following is NOT a ground for vacating a judgment or order under CPLR 5015?

The correct answer highlights a significant principle in New York's Civil Practice Law and Rules (CPLR) concerning the grounds upon which a party can seek to vacate a judgment or order. Under CPLR 5015, a party can seek to vacate a judgment or order for specific reasons, including fraud or misrepresentation by an adverse party, newly-discovered evidence that could not have been discovered prior to the original judgment, and instances of excusable default where a party fails to appear or defend in a case.

However, the reversal of a jury verdict is not a recognized ground for vacating a judgment or order under CPLR 5015. A jury verdict, once rendered and entered as a judgment, is final unless overturned on appeal or set aside through separate legal processes. The reasons to vacate judgments focus more on procedural issues or significant injustices that occurred during the original trial rather than the mere outcome of the verdict itself. Thus, a jury verdict being reversed does not fall under the grounds for vacating a judgment as outlined in this rule, making it the correct answer.