IRS Form 56
IRS Form 56 is the Notice Concerning Fiduciary Relationship.
IRS Form 56 is commonly used after a death to notify the IRS that a person or entity is now acting in a Fiduciary capacity for a deceased taxpayer, such as an Executor, Administrator or Trustee.
This officially designates the person who will be responsible for filing tax returns and paying taxes on behalf of the deceased taxpayer's Estate.
This form is also used again, after the estate is finally settled and closed, to notify the IRS that the fiduciary relationship has ended.