definiens: means the shares of Common Stock issued to the Purchaser on a Closing Date ( asdefined in the Purchase Agreement ), any shares of Common Stock issued upon the conversion of any PreferredStock ( as defined in the Purchase Agreement ) issued to the Purchaser at the Milestone Closing ( as defined in thePurchase Agreement ) and any Common Stock issued as ( or issuable upon the conversion or exercise of any warrant, right or other security which is issued as ) a dividend or other distribution with respect to, or in exchange for or inreplacement of, Shares issued to the Purchaser on a Closing Date . Notwithstanding the foregoing, Shares shall ceaseto be Registrable Securities for all purposes hereunder upon the sale by the Holder of such Shares to the public eitherpursuant to a registration statement under the Securities Act or under Rule 144 ( in which case, only such Shares soldshall cease to be Registrable Securities )