Tandem Diabetes Care®, Inc. (NASDAQ: TNDM), a medical device company and manufacturer of the only touchscreen insulin pumps available in the United States, today announced that it is proposing to offer and sell shares of its common stock, Series A warrants and Series B warrants to purchase shares of its common stock in an underwritten public offering. All of the shares of common stock and warrants to be sold in the offering are being offered by Tandem. The offering is subject to market conditions and there can be no assurance as to whether or when the offering may be completed, or as to the actual size or terms of the offering. The Company intends to use the net proceeds from the proposed offering for working capital and other general corporate purposes.

Oppenheimer & Co. Inc. is acting as the sole book‐running manager for the offering. National Securities Corporation, a wholly owned subsidiary of National Holdings Corporation (NasdaqCM: NHLD), is acting as a co-manager in connection with the offering.

This offering is being made pursuant to a shelf registration statement on Form S-3 that was previously filed by Tandem with the Securities and Exchange Commission and declared effective on December 19, 2014. A preliminary prospectus supplement and accompanying prospectus describing the terms of the proposed offering will be filed with the Securities and Exchange Commission and will form a part of the effective registration statement. When available, copies of the preliminary prospectus supplement and the accompanying prospectus relating to the securities being offered may be obtained from: Oppenheimer & Co. Inc. Attention: Syndicate Prospectus Department, 85 Broad St., 26th Floor, New York, NY 10004, by telephone at (212) 667-8563 or by email at EquityProspectus@opco.com. Electronic copies of the preliminary prospectus supplement and accompanying prospectus will also be available on the Securities and Exchange Commission’s website at www.sec.gov.

This news does not constitute an offer to sell or the solicitation of an offer to buy any of the securities described herein, nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction. The offering will be made only by means of a prospectus that forms a part of the registration statement.