I inherited an IRA that was passed down two different times; do I qualify for a 5-year disbursement?
When a traditional IRA owner dies after age 70.5 and after she has started taking her RMDs, the owner's own minimum distribution must still be taken during the year that death occurs. So yes, you will need to take her RMD before the end of the year of her death if your Grandma did not take her RMD that year. Otherwise there will be a 50% penalty tax imposed on the amount of the RMD in addition to income tax on the distribution actually taken.
Distributions must then begin by December 31st after the year the IRA owner died. You as the new beneficiary on that twice-inherited IRA must continue the schedule of RMDs that your Grandma was using, that is, no recalculation for your life expectancy. You must continue the RMD schedule of your Grandma which includes the 1.0 annual reduction.
Be sure to check with the IRA custodial as there can be varying rules.
The answer to this question can be slightly convoluted, I would call the company you custodian the assets at and have them look at the account and tell you how much you need to take. They will know. You should be able to stretch the IRA and will not be limited to the 5 year rule, but there are other factors that will play into this answer. Here is a link that can walk you through the rules of distribution. If you do not get an answer that sufices from the company managing the assets, I would call a tax adviser.
You can draw it over the 5 years. If you take that route, you do not need to take anything out this year- so long as the account balance is $0 by the times the 5 years is done.
Of course, depending on how much it is, whether you've been taking money out, and if you really want to stretch it, you could take the required minimum distributions out and take that over your lifetime as it continues to increase.