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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                  FORM 10-Q/A

<Table>
<C>        <S>
(mark one)
   [X]     QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
           SECURITIES EXCHANGE ACT OF 1934

             FOR THE QUARTERLY PERIOD ENDED MARCH 31, 2004

                                  OR

   [ ]     TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
           SECURITIES EXCHANGE ACT OF 1934

                    COMMISSION FILE NUMBER 1-15157
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                               PACTIV CORPORATION
             (Exact name of registrant as specified in its charter)

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<S>                                             <C>
                  DELAWARE                                       36-2552989
       (State or other jurisdiction of                        (I.R.S. Employer
       incorporation or organization)                        Identification No.)

            1900 WEST FIELD COURT
            LAKE FOREST, ILLINOIS                                   60045
  (Address of principal executive offices)                       (Zip Code)
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         REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: (847) 482-2000

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.  Yes [X]  No [ ]

     Indicate by check mark whether the registrant is an accelerated filer (as
defined in Rule 12b-2 of the Exchange Act).  Yes [X]  No [ ]

     Indicate the number of shares outstanding of each of the issuer's classes
of common stock as of the latest practicable date: Common stock, par value $0.01
per share: 153,181,785 as of April 30, 2004. (See Notes to Financial
Statements.)
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                                EXPLANATORY NOTE

     This amendment to Pactiv Corporation's Quarterly Report on Form 10-Q for
the quarter ended March 31, 2004, is being filed to amend Item 4. Controls and
Procedures, to conform the wording more closely to that required by Items 307
and 308(c) of Regulation S-K. No revisions have been made to the Pactiv
Corporation financial statements or any other disclosures contained in this
Quarterly Report.

ITEM 4. CONTROLS AND PROCEDURES

     The company's disclosure controls and procedures are designed to ensure
that information required to be disclosed by the company in the reports it files
or submits under the Securities Exchange Act is recorded, processed, summarized,
and reported within the appropriate time periods. The company, under the
supervision and with the participation of its management, including the
company's principal executive officer and principal financial officer, has
evaluated the effectiveness of its disclosure controls and procedures (as
defined in Exchange Act Rules 13a-15(e) and 15d-15(e)), and the company and such
officers have concluded that such controls and procedures were effective as of
the end of the period covered by this report. The company completed its
evaluation of such controls and procedures in connection with the preparation of
this quarterly report on Form 10-Q on April 28, 2004.

     There have been no significant changes in the company's internal controls
or in other factors that could significantly affect these controls subsequent to
the date of their evaluation, including any corrective actions with regard to
significant deficiencies and material weaknesses therein. There have been no
changes in internal control over financial reporting during the last fiscal
quarter that have materially affected, or are reasonably likely to affect,
internal controls over financial reporting.

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                                   SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

                                          PACTIV CORPORATION

                                          By: /s/ ANDREW A. CAMPBELL
                                            ------------------------------------
                                            Andrew A. Campbell
                                            Senior Vice President and Chief
                                              Financial Officer
                                            (principal financial and accounting
                                              officer)

Date:  January 31, 2005

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