We open accounts for individual trusts (non-business) both revocable and irrevocable. I know the beneficial ownership part (c) isn't applicable; however, we have been completing the control part on the form (a,b,d). Is this correct? I can't locate anything that tells me otherwise. Thank you in advance.

No, it does not meet the definition of a legal entity customer

https://www.federalregister.gov/document...al-institutions