The definition of alternate payee includes a spouse, a former spouse, or a child or other dependant of the participant.

So an alternate payee can be a current spouse right? When would this happen?

My understanding of IRC 414(p) is that divorce is not a requirement.

There has to be a court order, it has to relate alimony or property settlement, and it has to be pursuant to a state's domestic relations law.

So it would most likely be at least a legal separation.

You'd have to research state law to see what other circumstances would justify alimony or a property settlement.