Section 328.3 - Authorization for restrictive endorsements(a)By banks. Banks are authorized, under the conditions and in the form hereinafter provided, to place restrictive endorsements upon the face of bearer securities owned by themselves or their customers for the purpose of presentation to Federal Reserve banks or branches, or to the Bureau of the Fiscal Service, as follows:(1) For payment or redemption-at any time within 1 calendar month prior to their maturity date, or the date on which they become payable pursuant to a call for redemption, or at any time after their maturity or call date;(2) For exchange-during any period for their presentation pursuant to an exchange offering;(3) For redemption at par in payment of Federal estate taxes (only eligible securities)-at any time prior to their maturity or call redemption date; and(4) For conversion to book-entry securities under subpart O of part 306 of this chapter-at any time prior to their maturity or call redemption date.(b)By Service Center Directors and District Directors, Internal Revenue Service. Service Center Directors and District Directors, Internal Revenue Service, are authorized, under the conditions and in the form hereinafter provided, to place restrictive endorsements upon the face of bearer securities for the purpose of presentation to Federal Reserve banks or branches, or to the Bureau of the Fiscal Service, for redemption and application of the proceeds in payment of taxes (other than securities presented for redemption at par and application of the proceeds in payment of Federal estate taxes).(c)Instructions from Federal Reserve banks. Federal Reserve banks will inform eligible banks and Service Center Directors and District Directors, Internal Revenue Service, in their respective districts as to the procedure to be followed under the authority granted by these regulations. Restrictive endorsements shall not be placed on securities until such information is received from the Federal Reserve banks.