DexCom Announces a Follow-On Offering of Shares of Common Stock

Business Wire, April 6, 2006

SAN DIEGO -- DexCom, Inc. (Nasdaq:DXCM) today announced that it has filed a registration statement with the Securities and Exchange Commission for the proposed public offering of 4,200,000 shares of common stock, of which 1,200,000 shares are to be sold by DexCom and 3,000,000 are to be sold by selling stockholders. Piper Jaffray & Co. is the sole book-running manager for the offering. First Albany Capital Inc. is the co-lead manager. Lazard Capital Markets and Montgomery & Co., LLC are co-managers. It is expected that the underwriters will have an option to purchase up to an additional 630,000 shares of common stock from DexCom to cover over-allotments, if any.

Copies of the prospectus relating to the offering may be obtained, when available, from the offices of Piper Jaffray & Co., U.S. Bancorp Center, 800 Nicollet Mall, Suite 800, Minneapolis, MN 55402.

A registration statement relating to these securities has been filed with the Securities and Exchange Commission, but has not yet become effective. These securities may not be sold, nor may offers to buy be accepted, prior to the time the registration statement becomes effective. This press release shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of these securities in any state in which such offer, solicitation, or sale would be unlawful prior to registration or qualification under the securities laws of any such state.

About DexCom, Inc.

DexCom, Inc., headquartered in San Diego, California, is developing continuous glucose monitoring systems for people with diabetes.