FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN 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 * Allen Dick   2. Issuer Name and Ticker or Trading Symbol TANDEM DIABETES CARE INC [TNDM] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) C/O TANDEM DIABETES CARE, INC.,, 11075 ROSELLE STREET 3. Date of Earliest Transaction (Month/Day/Year) 03/08/2019 (Street) SAN DIEGO, CA 92121 4. If Amendment, Date Original Filed(Month/Day/Year) 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 Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 03/08/2019   S   6,100 D $ 62.71 (1) 200 D (2)   Common Stock 03/08/2019   S   200 D $ 63.22 (3) 0 D (2)   Common Stock 03/08/2019   S   6,300 D $ 62.29 0 I See Footnote (4) Common Stock 03/08/2019   S   418 D $ 62.53 2,000 I See Footnote (5) Common Stock 03/08/2019   S   418 D $ 62.53 2,000 I See Footnote (6) Common Stock 03/08/2019   S   3,803 D $ 62.79 (7) 14,300 I See Footnote (8) Common Stock 03/08/2019   S   300 D $ 63.21 (9) 14,000 I See Footnote (8) Common Stock               52,000 I See Footnote (10)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Allen Dick C/O TANDEM DIABETES CARE, INC., 11075 ROSELLE STREET SAN DIEGO, CA 92121	X

Signatures

s/ David B. Berger, Attorney-in-Fact for Dick P. Allen		03/11/2019
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(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 price reported reflects the weighted average price per share of multiple transactions with prices per share ranging between $62.19 and $63.18.
(2)	The securities are held in the Dick Allen Roth IRA.
(3)	The price reported reflects the weighted average price per share of multiple transactions with prices per share ranging between $63.19 and $63.245.
(4)	The securities are held in the Mary Allen Roth IRA. The Reporting Person is married to Mary Allen, and the Reporting Person may be deemed to have indirect beneficial ownership of such securities held in the Mary Allen Roth IRA. The Reporting Person disclaims beneficial ownership of such securities held in the Mary Allen Roth IRA.
(5)	The securities are held by the Gammon Children's 2000 Trust FBO Hannah Lee Gammon. The Reporting Person is co-trustee of the Gammon Children's 2000 Trust FBO Hannah Lee Gammon and has shared voting and investment power over the securities held by the Gammon Children's 2000 Trust FBO Hannah Lee Gammon and may be deemed to have indirect beneficial ownership of such securities. The Reporting Person disclaims beneficial ownership of such securities held by the Gammon Children's 2000 Trust FBO Hannah Lee Gammon.
(6)	The securities are held by the Gammon Children's 2000 Trust FBO Jake Allen Gammon. The Reporting Person is co-trustee of the Gammon Children's 2000 Trust FBO Jake Allen Gammon and has shared voting and investment power over the securities held by the Gammon Children's 2000 Trust FBO Jake Allen Gammon and may be deemed to have indirect beneficial ownership of such securities. The Reporting Person disclaims beneficial ownership of such securities held by the Gammon Children's 2000 Trust FBO Jake Allen Gammon.
(7)	The price reported reflects the weighted average price per share of multiple transactions with prices per share ranging between $62.1734 and $63.16.
(8)	The securities are held by Allen Cornerstone Ventures L.P. The Reporting Person is the managing partner of Allen Cornerstone Ventures L.P. and may be deemed to have indirect beneficial ownership of such securities. The Reporting Person disclaims beneficial ownership of such securities held by Allen Cornerstone Ventures L.P., except to the extent of his proportionate pecuniary interest therein.
(9)	The price reported reflects the weighted average price per share of multiple transactions with prices per share ranging between $63.20 and $63.24.
(10)	The securities are held by the Allen Family Trust dated October 12, 1981.

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