SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                  SCHEDULE 13G

             Information Statement Pursuant to Rules 13d-1 and 13d-2
                    Under the Securities Exchange Act of 1934
                                (Amendment No. 4)

                                 Stamps.com Inc.
                                (Name of Issuer)

                                  Common Shares
                         (Title of Class of Securities)

                                    852857200
                                 (CUSIP Number)

                                December 31, 2006
             (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
disclosures provided in a prior cover page.

The information required on 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).



CUSIP No. 852857200

--------------------------------------------------------------------------------
1.   NAME OF REPORTING PERSONS
     I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

     Passport Global Master Fund SPC Ltd for and on behalf of Portfolio A -
     Global Strategy
--------------------------------------------------------------------------------
2.   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

                                                                 (a)  |_|
                                                                 (b)  |X|
--------------------------------------------------------------------------------
3.   SEC USE ONLY


--------------------------------------------------------------------------------
4.   CITIZENSHIP OR PLACE OF ORGANIZATION

     British Virgin Islands
--------------------------------------------------------------------------------
               5.   SOLE VOTING POWER

                    -0-
               -----------------------------------------------------------------
  NUMBER OF    6.   SHARED VOTING POWER
   SHARES
BENEFICIALLY        1,756,700 (see Item 4)
  OWNED BY     -----------------------------------------------------------------
    EACH       7.   SOLE DISPOSITIVE POWER
  REPORTING
   PERSON           -0-
    WITH       -----------------------------------------------------------------
               8.   SHARED DISPOSITIVE POWER

                    1,756,700 (see Item 4)
--------------------------------------------------------------------------------
9.   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     1,756,700
--------------------------------------------------------------------------------
10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

                                                                          |_|
--------------------------------------------------------------------------------
11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

     7.71%
--------------------------------------------------------------------------------
12.  TYPE OF REPORTING PERSON

     PN
--------------------------------------------------------------------------------



CUSIP No. 852857200

--------------------------------------------------------------------------------
1.   NAME OF REPORTING PERSONS
     I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

     Partners Group Alternative Strategies PCC Limited Gold Iota Cell
--------------------------------------------------------------------------------
2.   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

                                                                 (a)  |_|
                                                                 (b)  |X|
--------------------------------------------------------------------------------
3.   SEC USE ONLY


--------------------------------------------------------------------------------
4.   CITIZENSHIP OR PLACE OF ORGANIZATION

     Guernsey
--------------------------------------------------------------------------------
               5.   SOLE VOTING POWER

                    -0-
               -----------------------------------------------------------------
  NUMBER OF    6.   SHARED VOTING POWER
   SHARES
BENEFICIALLY        107,650 (see Item 4)
  OWNED BY     -----------------------------------------------------------------
    EACH       7.   SOLE DISPOSITIVE POWER
  REPORTING
   PERSON           -0-
    WITH       -----------------------------------------------------------------
               8.   SHARED DISPOSITIVE POWER

                    107,650 (see Item 4)
--------------------------------------------------------------------------------
9.   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     107,650
--------------------------------------------------------------------------------
10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

                                                                          |_|
--------------------------------------------------------------------------------
11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

     0.47%
--------------------------------------------------------------------------------
12.  TYPE OF REPORTING PERSON

     PN
--------------------------------------------------------------------------------



CUSIP No. 852857200

--------------------------------------------------------------------------------
1.   NAME OF REPORTING PERSONS
     I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

     Passport Holdings, LLC
--------------------------------------------------------------------------------
2.   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

                                                                 (a)  |_|
                                                                 (b)  |X|
--------------------------------------------------------------------------------
3.   SEC USE ONLY


--------------------------------------------------------------------------------
4.   CITIZENSHIP OR PLACE OF ORGANIZATION

     Delaware
--------------------------------------------------------------------------------
               5.   SOLE VOTING POWER

                    -0-
               -----------------------------------------------------------------
  NUMBER OF    6.   SHARED VOTING POWER
   SHARES
BENEFICIALLY        1,864,350 (see Item 4)
  OWNED BY     -----------------------------------------------------------------
    EACH       7.   SOLE DISPOSITIVE POWER
  REPORTING
   PERSON           -0-
    WITH       -----------------------------------------------------------------
               8.   SHARED DISPOSITIVE POWER

                    1,864,350 (see Item 4)
--------------------------------------------------------------------------------
9.   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     1,864,350
--------------------------------------------------------------------------------
10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

                                                                          |_|
--------------------------------------------------------------------------------
11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

     8.19%
--------------------------------------------------------------------------------
12.  TYPE OF REPORTING PERSON

     OO
--------------------------------------------------------------------------------



CUSIP No. 852857200

--------------------------------------------------------------------------------
1.   NAME OF REPORTING PERSONS
     I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

     Passport Management, LLC
--------------------------------------------------------------------------------
2.   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

                                                                 (a)  |_|
                                                                 (b)  |X|
--------------------------------------------------------------------------------
3.   SEC USE ONLY


--------------------------------------------------------------------------------
4.   CITIZENSHIP OR PLACE OF ORGANIZATION

     Delaware
--------------------------------------------------------------------------------
               5.   SOLE VOTING POWER

                    -0-
               -----------------------------------------------------------------
  NUMBER OF    6.   SHARED VOTING POWER
   SHARES
BENEFICIALLY        1,864,350 (see Item 4)
  OWNED BY     -----------------------------------------------------------------
    EACH       7.   SOLE DISPOSITIVE POWER
  REPORTING
   PERSON           -0-
    WITH       -----------------------------------------------------------------
               8.   SHARED DISPOSITIVE POWER

                    1,864,350 (see Item 4)
--------------------------------------------------------------------------------
9.   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     1,864,350
--------------------------------------------------------------------------------
10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

                                                                          |_|
--------------------------------------------------------------------------------
11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

     8.19%
--------------------------------------------------------------------------------
12.  TYPE OF REPORTING PERSON

     OO
--------------------------------------------------------------------------------



CUSIP No. 852857200

--------------------------------------------------------------------------------
1.   NAME OF REPORTING PERSONS
     I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

     Passport Capital, LLC
--------------------------------------------------------------------------------
2.   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

                                                                 (a)  |_|
                                                                 (b)  |X|
--------------------------------------------------------------------------------
3.   SEC USE ONLY


--------------------------------------------------------------------------------
4.   CITIZENSHIP OR PLACE OF ORGANIZATION

     Delaware
--------------------------------------------------------------------------------
               5.   SOLE VOTING POWER

                    -0-
               -----------------------------------------------------------------
  NUMBER OF    6.   SHARED VOTING POWER
   SHARES
BENEFICIALLY        1,864,350 (see Item 4)
  OWNED BY     -----------------------------------------------------------------
    EACH       7.   SOLE DISPOSITIVE POWER
  REPORTING
   PERSON           -0-
    WITH       -----------------------------------------------------------------
               8.   SHARED DISPOSITIVE POWER

                    1,864,350 (see Item 4)
--------------------------------------------------------------------------------
9.   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     1,864,350
--------------------------------------------------------------------------------
10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

                                                                          |_|
--------------------------------------------------------------------------------
11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

     8.19%
--------------------------------------------------------------------------------
12.  TYPE OF REPORTING PERSON

     OO
--------------------------------------------------------------------------------



CUSIP No. 852857200

--------------------------------------------------------------------------------
1.   NAME OF REPORTING PERSONS
     I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

     John Burbank
--------------------------------------------------------------------------------
2.   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

                                                                 (a)  |_|
                                                                 (b)  |X|
--------------------------------------------------------------------------------
3.   SEC USE ONLY


--------------------------------------------------------------------------------
4.   CITIZENSHIP OR PLACE OF ORGANIZATION

     United States
--------------------------------------------------------------------------------
               5.   SOLE VOTING POWER

                    -0-
               -----------------------------------------------------------------
  NUMBER OF    6.   SHARED VOTING POWER
   SHARES
BENEFICIALLY        1,864,350 (see Item 4)
  OWNED BY     -----------------------------------------------------------------
    EACH       7.   SOLE DISPOSITIVE POWER
  REPORTING
   PERSON           -0-
    WITH       -----------------------------------------------------------------
               8.   SHARED DISPOSITIVE POWER

                    1,864,350 (see Item 4)
--------------------------------------------------------------------------------
9.   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

     1,864,350
--------------------------------------------------------------------------------
10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES

                                                                          |_|
--------------------------------------------------------------------------------
11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

     8.19%
--------------------------------------------------------------------------------
12.  TYPE OF REPORTING PERSON

     IN
--------------------------------------------------------------------------------



Item 1(a).  Name of Issuer:

            Stamps.com Inc. (the "Company").

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

            12959 Coral Tree Place
            Los Angeles, California 90066

Item 2(a).  Name of Persons Filing:

            Passport Global Master Fund SPC Ltd for and on behalf of Portfolio A
            - Global Strategy ("Fund I");
            Partners Group Alternative Strategies PCC Limited Gold Iota Cell
            ("Fund II");
            Passport Management, LLC ("Passport Management");
            Passport Holdings, LLC ("Passport Holdings")
            Passport Capital, LLC ("Passport Capital"); and
            John Burbank ("Burbank," together with Fund I, Fund II, Passport
               Management, Passport Holdings and Passport Capital, the
               "Reporting Persons").

            Burbank is the sole managing member of Passport Capital; Passport
            Capital is the sole managing member of Passport Holdings and
            Passport Management. Passport Management is the investment manager
            to Fund I and Trading Advisor to Fund II. As a result, each of
            Passport Management, Passport Holdings, Passport Capital and Burbank
            may be considered to share the power to vote or direct the vote of,
            and the power to dispose or direct the disposition of, the Shares
            owned of record by Fund I and Fund II. This statement on Schedule
            13G shall not be construed as an admission that any of the Reporting
            Persons (other than Fund I and Fund II) is the beneficial owner of
            the securities covered by this statement.

Item 2(b).  Address of Principal Business Office:

            For each Reporting Person:

            PASSPORT CAPITAL, LLC
            402 JACKSON STREET
            SAN FRANCISCO, CA 94111

Item 2(c).  Citizenship:

            See row 4 of each Reporting Persons' respective cover page.

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

            Common Shares of the Company (the "Common Shares")

Item 2(e).  CUSIP Number:

            852857200

Item 3.     Not applicable.



Item 4.     Ownership.

            (a)   Amount beneficially owned:

                  See Item 9 of each Reporting Persons' respective cover page.

            (b)   Percent of class:

                  See Item 11 of each Reporting Persons' respective cover page.

            (c)   Number of shares for which each Reporting Person has sole or
                  shared voting on disposition:

                  See Items 5-8 of each Reporting Persons' respective cover
                  page.

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

            If this statement is being filed to report the fact that as of
            the date hereof the reporting person has ceased to be the
            beneficial owner of more than five percent of the class of
            securities, check the following |_|.

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.

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 14, 2007
       -----------------

                                     PASSPORT GLOBAL MASTER FUND SPC LTD FOR
                                     AND ON BEHALF OF PORTFOLIO A -
                                     GLOBAL STRATEGY


                                          By: /s/ JOHN BURBANK
                                              ----------------------------------
                                              John Burbank
                                              Director


                                     PARTNERS GROUP ALTERNATIVE STRATEGIES PCC
                                     LIMITED GOLD IOTA CELL

                                          By: PASSPORT MANAGEMENT, LLC
                                              as Trading Advisor

                                          By: PASSPORT CAPITAL, LLC,
                                              as Managing Member

                                          By: /s/ JOHN BURBANK
                                             -----------------------------------
                                             John Burbank,
                                             Managing Member


                                     PASSPORT HOLDINGS, LLC

                                          By: PASSPORT CAPITAL, LLC,
                                              as Managing Member

                                          By: /s/ JOHN BURBANK
                                             -----------------------------------
                                             John Burbank,
                                             Managing Member


                                     PASSPORT MANAGEMENT, LLC

                                         By: PASSPORT CAPITAL, LLC,
                                             as Managing Member

                                         By: /s/ JOHN BURBANK
                                             -----------------------------------
                                             John Burbank,
                                             Managing Member


                                     PASSPORT CAPITAL, LLC

                                     By: /s/ JOHN BURBANK
                                         ---------------------------------------
                                         John Burbank,
                                         Managing Member


                                     /s/ JOHN BURBANK
                                     -------------------------------------------
                                     John Burbank



                                                                       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 the statement on Schedule 13G to which this agreement is attached as an
exhibit.

      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 14, 2007.

                                     PASSPORT GLOBAL MASTER FUND SPC LTD
                                     FOR AND ON BEHALF OF PORTFOLIO A -
                                     GLOBAL STRATEGY

                                         By: /s/ JOHN BURBANK
                                             -----------------------------------
                                             John Burbank
                                             Director


                                     PARTNERS GROUP ALTERNATIVE STRATEGIES PCC
                                     LIMITED GOLD IOTA CELL

                                         By: PASSPORT MANAGEMENT, LLC
                                             as Trading Advisor

                                         By: PASSPORT CAPITAL, LLC,
                                             as Managing Member

                                         By: /s/ JOHN BURBANK
                                             -----------------------------------
                                             John Burbank,
                                             Managing Member


                                     PASSPORT HOLDINGS, LLC

                                         By: PASSPORT CAPITAL, LLC,
                                             as Managing Member

                                         By: /s/ JOHN BURBANK
                                             -----------------------------------
                                             John Burbank,
                                             Managing Member


                                     PASSPORT MANAGEMENT, LLC

                                         By: PASSPORT CAPITAL, LLC,
                                             as Managing Member

                                         By: /s/ JOHN BURBANK
                                             -----------------------------------
                                             John Burbank,
                                             Managing Member


                                     PASSPORT CAPITAL, LLC

                                     By: /s/ JOHN BURBANK
                                         ---------------------------------------
                                         John Burbank,
                                         Managing Member

                                     /s/ JOHN BURBANK
                                     -------------------------------------------
                                     John Burbank