Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  BLICKENSTAFF KIM D
2. Date of Event Requiring Statement (Month/Day/Year)
11/13/2013
3. Issuer Name and Ticker or Trading Symbol
TANDEM DIABETES CARE INC [TNDM]
(Last)
(First)
(Middle)
C/O TANDEM DIABETES CARE, INC.,, 11045 ROSELLE STREET
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
PRESIDENT AND CEO
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

SAN DIEGO, CA 92121
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 81,617
I
See footnote (1)
Common Stock (2) 14,920
I
See footnote (1)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Series A Preferred Stock   (3)   (4) Common Stock 18,310 $ 0 I See footnote (1)
Series B Preferred Stock   (3)   (4) Common Stock 75,938 $ 0 I See footnote (1)
Series D Preferred Stock   (3)   (4) Common Stock 217,154 $ 0 I See footnote (1)
Preferred Stock Warrant   (5) 05/25/2022 Series D Preferred Stock (6) 45,450 (6) $ 4.4 (6) I See footnote (1)
Preferred Stock Warrant   (5) 07/03/2022 Series D Preferred Stock (7) 181,818 (7) $ 4.4 (7) I See footnote (1)
Incentive Stock Option (8)   (9)   (10) Common Stock 271,272 $ 1.11 D  
Stock Option (8)   (9)   (10) Common Stock 303,446 $ 1.11 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
BLICKENSTAFF KIM D
C/O TANDEM DIABETES CARE, INC.,
11045 ROSELLE STREET
SAN DIEGO, CA 92121
  X     PRESIDENT AND CEO  

Signatures

/s/ David B. Berger, Attorney-in-Fact for Kim D. Blickenstaff 11/13/2013
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) The securities are held by the Kim Blickenstaff Revocable Trust dated April 15, 2010.
(2) Restricted stock issued pursuant to the Issuer's Tandem Diabetes Care, Inc. 2006 Stock Incentive Plan. These shares vested as to 25% on 10/20/2012 and continue to vest in 36 equal monthly installments thereafter, and will automatically vest in full upon consummation of the Issuer's initial public offering.
(3) The securities are immediately convertible.
(4) The expiration date is not relevant to the conversion of these securities.
(5) The warrants are immediately exercisable.
(6) Upon the consummation of the Issuer's initial public offering, these warrants will automatically become exercisable for 27,124 shares of the Issuer's common stock at an exercise price of $7.37 per share.
(7) Upon the consummation of the Issuer's initial public offering, these warrants will automatically become exercisable for 108,509 shares of the Issuer's common stock at an exercise price of $7.37 per share.
(8) Granted pursuant to the Issuer's Tandem Diabetes Care, Inc. 2006 Stock Incentive Plan.
(9) The date of the option was 4/23/2013. All shares subject to the option will vest in 24 equal monthly installments commencing on 4/23/2013.
(10) The expiration date for these options is 10 years from the date of grant.

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