Code of Federal Regulations Title 31. Money and Finance–Treasury § 31.337.2 Transportation charges and risks

Debentures presented for redemption at call or maturity, or for authorized prior purchase, or for conversion to book-entry form, must be delivered at the expense and risk of the holder. Debentures bearing restricted assignments may be forwarded by registered mail, but for the owner's protection debentures bearing unrestricted assignments should be forwarded by insured registered mail.