5 CFR 831.2005: Designation of beneficiary for lump-sum payment.

(a) The Designation of Beneficiary must be in writing, signed, and witnessed,and received in OPM before the death of the designator.

(b) No change or cancellation of beneficiary in a last will or testament, or in any other document not witnessed and filed as required by this section, has any force or effect.

(c) A witness to a Designation of Beneficiary is ineligible to receive payment as a beneficiary.

(d) Any person, firm, corporation, or legal entity may be named as beneficiary.

(e) A change of beneficiary may be made at any time and without the knowledge or consent of the previous beneficiary, and this right cannot be waived or restricted.