Non-spouse Roth beneficiary - no RMDs taken

[CBCPA]

Daughter inherited mother's Roth account 18 years ago and was not informed about RMD requirement, so no distributions taken.  Mother over 59 1/2 but had not held account for 5 years at death.  No options for daughter now except draining account?  Since daughter has held account for 5 years, are earnings taxable?  What would penalty for lack of RMDs be based on - just the earnings?

[card]

Assets would be qualified (fully nontaxable) after 5 years, combining mother and daughter holding periods. There are no special rules for Roth post-death RMDs- the penalty is 50% of the amount that should have been distributed, but wasn't, each year.

You might want to take a look at IRS Info Letter 2016-0071. And also research how many years back the IRS can look in this situation. Good luck...