I'm responding here because my Details box didn't work. Thank you for all the many excellent leads. I believe this may happen somewhat often: Wealthy person with revocable trust (using SSN) dies mid-2021. Morgan Stanley did not split the 2021 report between revocable and irrevocable trust income. I too put it all in personal return per 1099-div packages. In 2022 Morgan Stanley still produced 1099-div Trust reports in SSN. Trustee is a lovely 93-yr old widower who is struggling with early mental decline. He will get me in touch with daughter who will be designated as trustee. Morgan Stanley manages his enormous wealth -- was there no one in their staff to guide a new widower client through this? (Last year estate of the deceased paid 1/2 mil in unnecessary taxes because no beneficiary was listed in an annuity contract. I'm sorry I'm venting.) Finally my question: If I belatedly get an EIN and file the trust return, can I attach a statement that income was erroneously reported under such-and-such SSN.