I recently updated the beneficiaries on my tax-deferred account and Roth IRA. The form for the Roth requested name, address, date of birth, SSN, relationship to me, whether primary or contingent beneficiary and what proportion of the account each should receive. I don't know how much of that info they'd have been willing to do without if I didn't know it. I don't see the form from my tax-deferred plan but IIRC it was pretty similar. For the beneficiaries I also had to declare my marital status.