Tandem Diabetes Care, Inc. (NASDAQ:TNDM) Files An 8-K Other Events
Item 8.01 Other Events

On October 17, 2017, Tandem Diabetes Care, Inc. (the “Company”)closed the previously announced underwritten public offering of its common stock. In the offering, the Company sold (i) 4,630,000shares of Common Stock, (ii)Series A Warrants to purchase an aggregate of 4,630,000shares of Common Stock and (iii)Series B Warrants to purchase an aggregate of 4,630,000shares of Common Stock, at a public offering price of $3.50 per share and accompanying Warrants, less the Underwriters’ discount. The net proceeds to the Company from the Offering, after deducting the Underwriters’ discount and other estimated offering expenses payable by the Company, are expected to be approximately $14.8 million, assuming no exercise of the warrants. The net proceeds from the Offering will be used for working capital and general corporate purposes.

The Series A Warrants have an exercise price of $3.50 per share, are immediately exercisable and will expire five years from the date of issuance.

The Series B Warrants have an exercise price of $3.50 per share, are immediately exercisable and will expire six months from the date of issuance.

Oppenheimer & Co. Inc. acted as the sole book‐running manager for the offering. National Securities Corporation acted as co‐manager.

The offer and sale of the shares and warrants was made by the Company to aprospectusdated December 19, 2014 and a prospectus supplementdated October 13, 2017, in connection with a takedown from the Company’s shelf registration statement onForm S-3(File No.333-200686), previously declared effective by the Securities and Exchange Commission and a related registration statement on Form S-3 (File No. 333-220929) filed by the Company with the Securities and Exchange Commission on October 13, 2017 to rule 462(b) of the Securities Act of 1933, as amended.

This Current Report on Form 8-K shall not constitute an offer to sell or the solicitation of an offer to buy these securities, 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.

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About Tandem Diabetes Care, Inc. (NASDAQ:TNDM)

Tandem Diabetes Care, Inc. is a medical device company. The Company is engaged in designing, developing and commercializing products for people with insulin-dependent diabetes. The Company manufactures and sells three insulin pump products, which include t:slim Insulin Delivery System (t:slim), t:flex Insulin Delivery System (t:flex) and t:slim G4 Insulin Delivery System (t:slim G4). Its technology platform features Micro-Delivery Technology, a miniaturized pumping mechanism, which draws insulin from a flexible bag within the pump’s cartridge rather than relying on a syringe and plunger mechanism. It also features a software, which is a vivid color touch screen and a micro- universal serial bus (USB) connection that supports both a rechargeable battery and uploads to t:connect Diabetes Management Application (t:connect), its custom cloud-based data management application that provides display therapy management data from the pump and supported blood glucose meters.