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 *
  Delphi Management Partners VIII, L.L.C.
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)
3000 SAND HILL ROAD,, BUILDING 1, SUITE 135
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

MENLO PARK, CA 94025
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ 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)

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 C Preferred Stock   (1)   (2) Common Stock 664,565 $ 0 I See footnote (3)
Series C Preferred Stock   (1)   (2) Common Stock 6,488 $ 0 I See footnote (4)
Series D Preferred Stock   (1)   (2) Common Stock 2,967,987 $ 0 I See footnote (3)
Series D Preferred Stock   (1)   (2) Common Stock 28,979 $ 0 I See footnote (4)

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Delphi Management Partners VIII, L.L.C.
3000 SAND HILL ROAD,
BUILDING 1, SUITE 135
MENLO PARK, CA 94025
    X    
DELPHI VENTURES VIII LP
3000 SAND HILL ROAD
BUILDING 1, SUITE 135
MENLO PARK, CA 94025
    X    
Delphi BioInvestments VIII LP
3000 SAND HILL ROAD
BUILDING 1, SUITE 135
MENLO PARK, CA 94025
    X    
ROEDER DOUGLAS A
3000 SAND HILL ROAD
BUILDING 1, SUITE 135
MENLO PARK, CA 94025
  X   X    
BOCHNOWSKI JAMES J
3000 SAND HILL ROAD
BUILDING 1, SUITE 135
MENLO PARK, CA 94025
    X    
DOUGLASS DAVID L
3000 SAND HILL ROAD
BUILDING 1, SUITE 135
MENLO PARK, CA 94025
    X    
PAKIANATHAN DEEPIKA
3000 SAND HILL ROAD
BUILDING 1, SUITE 135
MENLO PARK, CA 94025
    X    

Signatures

/s/ David B. Berger, Attorney-in-Fact for Delphi Management Partners VIII, L.L.C. 11/13/2013
**Signature of Reporting Person Date

/s/ David B. Berger, Attorney-in-Fact for Delphi Ventures VIII, L.P. 11/13/2013
**Signature of Reporting Person Date

/s/ David B. Berger, Attorney-in-Fact for Delphi BioInvestments VIII, L.P. 11/13/2013
**Signature of Reporting Person Date

/s/ David B. Berger, Attorney-in-Fact for Douglas A. Roeder 11/13/2013
**Signature of Reporting Person Date

/s/ David B. Berger, Attorney-in-Fact for James T. Bochnowski 11/13/2013
**Signature of Reporting Person Date

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

/s/ David B. Berger, Attorney-in-Fact for Deepika R. Pakianathan 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 immediately convertible.
(2) The expiration date is not relevant to the conversion of these securities.
(3) The reported securities are owned directly by Delphi Ventures VIII, L.P. ("DV VIII"). Delphi Management Partners VIII, L.L.C. (the "General Partner"), as general partner of Delphi Ventures VIII, L.P., and Douglas A. Roeder, James J. Bochnowski, David L. Douglass and Deepika R. Pakianathan, Ph.D., the managing members of the General Partner, may be deemed to share voting and dispositive power over the reported securities but each disclaims beneficial ownership in the securities held by DV VIII, except to the extent of their pecuniary interest therein.
(4) The reported securities are owned directly by Delphi BioInvestments VIII, L.P. ("DBI VIII"). The General Partner, as general partner of Delphi BioInvestments VIII, L.P., and Douglas A. Roeder, James J. Bochnowski, David L. Douglass and Deepika R. Pakianathan, Ph.D., the managing members of the General Partner, may be deemed to share voting and dispositive power over the reported securities but each disclaims beneficial ownership in the securities held by DBI VIII, except to the extent of their pecuniary interest therein.

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