SECURITIES AND EXCHANGE COMMISSION
                              Washington, DC 20549



                                  SCHEDULE 13G
                                 (Rule 13d-102)

INFORMATION  TO  BE  INCLUDED  IN  THE   STATEMENTS   FILED  PURSUANT  TO  RULES
13d-1(b)(c), AND (d) AND AMENDMENTS THERETO FILED PURSUANT TO RULE 13d-2(b)

                                                 (Amendment No. 3)*

                                   Dexcom Inc.
                                (Name of Issuer)


                    Common Stock, par value $0.001 per share
                         (Title of Class of Securities)


                                    252131107
                                 (CUSIP Number)

                                 December 31, 2009
             (Date of Event Which Requires Filing of this Statement)

Check the  appropriate box to designate the rule pursuant to which this Schedule
is filed:

         |_|      Rule 13d-1(b)

         |X|      Rule 13d-1(c)

         |_|      Rule 13d-1(d)

*The  remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for any  subsequent  amendment  containing  information  which  would  alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the  Securities  Exchange  Act of
1934 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).








                                  SCHEDULE 13G
CUSIP NO. 252131107

                      NAMES OF REPORTING PERSONS
                      I.R.S. IDENTIFICATION  NOS.  OF  ABOVE  PERSONS  (Entities
                      Only)
         1

                      Michael  A.  Roth  and  Brian  J. Stark, as  joint  filers
                      pursuant to Rule 13d-1(k).

         2            CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
                      (a) |X|
                      (b) |_|

         3            SEC USE ONLY

         4            CITIZENSHIP OR PLACE OF ORGANIZATION

                      United States of America

          NUMBER OF                    SOLE VOTING POWER
                                 5
            SHARES                     0

         BENEFICIALLY                  SHARED VOTING POWER
                                 6
        OWNED BY EACH                  Common Stock equal to less than 5%

          REPORTING                    SOLE DISPOSITIVE POWER
                                 7
                                       0
         PERSON WITH
                                       SHARED DISPOSITIVE POWER
                                 8
                                       Common Stock equal to less than 5%

                      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
                      PERSON
         9
                      Common Stock equal to less than 5%

                      CHECK  BOX  IF  THE  AGGREGATE  AMOUNT IN ROW (9) EXCLUDES
                      CERTAIN SHARES                                        [__]
         10

                      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
         11
                      Less than 5%

                      TYPE OF REPORTING PERSON
         12
                      IN



CUSIP NO. 252131107

Item 1(a).        Name of Issuer:

                  Dexcom Inc.(the "Issuer").

Item 1(b).        Address of Issuer's Principal Executive Offices:

                  5555 Oberlin Drive
                  San Diego, CA 92121


Items 2(a),
(b) and (c).      Name  of  Persons Filing, Address of Principal Business Office
                  and Citizenship:

                  This Amendment No. 3 to Schedule 13G is being  filed on behalf
                  of  Michael  A.  Roth  and  Brian  J.  Stark, as joint  filers
                  (collectively, the "Reporting Persons").

                  The  Reporting  Persons   have  entered  into a  Joint  Filing
                  Agreement, a copy of which is  filed with this Amendment No. 3
                  to Schedule 13G as Exhibit 1, pursuant to which the  Reporting
                  Persons  have  agreed  to  file  this Schedule  13G jointly in
                  accordance  with  the  provisions  of  Rule  13d-1(k)  of  the
                  Securities  Exchange  Act of  1934, as amended (the  "Exchange
                  Act").

                  The  principal  business  office of the  Reporting  Persons is
                  3600 South Lake Drive,  St. Francis,  WI  53235. The Reporting
                  Persons are citizens of the United States of America.

Item 2(d).        Title of Class of Securities:

                  Common Stock, par value $0.001 per share (the "Common  Stock")

Item 2(e).        CUSIP Number:

                  252131107

Item 3.           Not applicable.

Item 4.           Ownership.

                  (a)  Amount beneficially owned:

                       Common Stock equal to less than 5%

                  (b)  Percent of class:  Less than 5%

                  (c)  Number of shares to which such person has:

                       (i)  Sole power to vote or direct the vote: 0

                       (ii) Shared  power  to  vote  or  direct the vote: Common
                            Stock equal to less than 5%

                       (iii) Sole power to dispose or to direct the  disposition
                             of: 0

                       (iv) Shared power to dispose of or direct the disposition
                            of: Common Stock equal to less than 5%

Item 5.           Ownership of Five Percent or Less of a Class.

                  This statement is being filed  to report the fact  that as  of
                  the date hereof the reporting persons  have  ceased  to be the
                  beneficial  owner of more  than  five  percent of the class of
                  of securities, check the following [X]

Item 6.           Ownership of  More  than  Five  Percent on  Behalf  of Another
                  Person.

                  Not applicable

Item 7.           Identification  and  Classification  of  the  Subsidiary Which
                  Acquired  the  Security  Being  Reported By the Parent Holding
                  Company.

                  Not applicable

Item 8.           Identification  and  Classification  of  Members of the Group.

                  Not applicable




CUSIP NO. 252131107

Item 9.           Notice of Dissolution of a Group.

                  Not applicable

Item 10.          Certification.

                    By signing below I certify that, to the best of my knowledge
                    and  belief,  the  securities  referred  to  above  were not
                    acquired  and are not  held for the  purpose  of or with the
                    effect of changing or influencing  the control of the issuer
                    of the  securities and were not acquired and are not held in
                    connection  with  or as a  participant  in  any  transaction
                    having that purpose or effect.



                                    SIGNATURE


After  reasonable inquiry and to the best of my  knowledge and belief, I certify
that the  information set forth in this statement is true, complete and correct.

Dated:   February 16, 2010



                                 /s/ Michael A. Roth
                                 Michael A. Roth


                                 /s/ Brian J. Stark
                                 Brian J. Stark






CUSIP NO. 252131107


                                                                       Exhibit 1
                             JOINT FILING AGREEMENT



     In accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934,
as amended,  the undersigned agree to the joint filing on behalf of each of them
of a  statement on Schedule  13G (including  amendments thereto) with respect to
certain shares of Common Stock of Dexcom, Inc. and further agree that this Joint
Filing  Agreement  shall be included as an exhibit to such joint filings.

     The undersigned further agree that each party hereto is responsible for the
timely  filing of such  Schedule  13G and any  amendments  thereto,  and for the
completeness  and accuracy of the  information  concerning  such party contained
therein; provided, however, that no party is responsible for the completeness or
accuracy of the information concerning any other party making the filing, unless
such party knows or has reason to believe that such information is inaccurate.

     IN WITNESS  WHEREOF,  the parties have executed this Joint Filing Agreement
on February 16, 2010.



                                 /s/ Michael A. Roth
                                 Michael A. Roth


                                 /s/ Brian J. Stark
                                 Brian J. Stark