Does aggregation pro-rata rule apply to mega backdoor rollovers of after-tax 401k funds to Roth IRA?
I.e., should the rollover amount also include the pre-tax funds in the proportion calculated based on all traditional IRAs owned by the individual?
It is my understanding that such requirement applies to backdoor (not mega) rollovers from a traditional IRA to Roth IRA. If available, please provide a reference to the specific source (IRS publication?) explaining the answer to this question.
