UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

                               _________________


                                    FORM 8-K


                                 CURRENT REPORT
                     Pursuant to Section 13 or 15(d) of the
                        Securities Exchange Act of 1934


 Date of Report (Date of Earliest Event Reported): July 12, 2005 (July 6, 2005)


                         PacifiCare Health Systems, Inc
             (Exact Name of Registrant as Specified in its Charter)


          Delaware                      001-31700                 95-4591529
(State or Other Jurisdiction         (Commission File           (IRS Employer
      of Incorporation)                  Number)             Identification No.)


           5995 Plaza Dr. Cyprus, California                  90630-5028
       (Address of Principal Executive Offices)               (Zip Code)


                                 (714) 952-1121
              (Registrant's telephone number, including area code)


         Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions:

|_|    Written communications pursuant to Rule 425 under the Securities Act
       (17 CFR 230.425)

|_|    Soliciting material pursuant to Rule 14a-12 under the Exchange Act
       (17 CFR 240.14a-12)

|_|    Pre-commencement communications pursuant to Rule 14d-2(b)
       under the Exchange Act (17 CFR 240.14d-2(b))

|_|    Pre-commencement communications pursuant to Rule 13e-4(c)
       under the Exchange Act (17 CFR 240.13e-4(c))

Item 3.03.        Material Modification to Rights of Security Holders.

         PacifiCare Health Systems, Inc., a Delaware corporation (the
"Company"), entered into two amendments to its Rights Agreement, dated as of
November 19, 1999, between the Company and ChaseMellon Shareholder Services,
L.L.C. (predecessor to Mellon Investor Services, LLC ("Mellon")), as rights
agent (the "Rights Agreement"). Unless otherwise noted, capitalized terms used
but not defined herein shall have the meaning assigned thereto in the Rights
Agreement. The initial amendment was entered into as of February 9, 2005 by
the Company, Mellon and Computershare Investor Services, LLC ("Computershare")
(the "First Amendment") and the second amendment was entered into as of July
6, 2005 by the Company and Computershare (the "Second Amendment").

         The First Amendment removed Mellon as rights agent and appointed
Computershare as successor Rights Agent. The Second Amendment was authorized
by the Board of Directors of the Company in connection with the Agreement and
Plan of Merger, dated as of July 6, 2005 (the "Merger Agreement"), with the
Company, UnitedHealth Group Incorporated, a Minnesota corporation ("Parent")
and Point Acquisition LLC, a limited liability company organized under the
laws of the State of Delaware. The Second Amendment provides that (i) neither
Parent nor any of its Subsidiaries, Affiliates or Associates shall be deemed
to be an Acquiring Person or a Principal Party by virtue of the execution of
the Merger Agreement or the consummation of the transactions contemplated
thereby, (ii) none of a Shares Acquisition Date, Distribution Date or
Transaction shall be deemed to have occurred by reason of the execution of the
Merger Agreement or consummation of the transactions contemplated thereby,
(iii) the Final Expiration Date of the Rights Agreement shall occur on the
earlier of the Close of Business on November 19, 2009 or immediately prior to
the Effective Time (as defined in the Merger Agreement) and (iv) the Rights
Agreement and the Rights established thereby will terminate immediately prior
to the Effective Time (as defined in the Merger Agreement).

         The Rights Agreement, including the form of the Rights Certificate,
is filed as an exhibit to the Registration Statement on Form 8-K filed with
the Securities and Exchange Commission on November 19, 1999 and is
incorporated herein by reference. The foregoing descriptions of the First
Amendment and the Second Amendment do not purport to be complete and are
qualified in their entirety by reference to the First Amendment, which is
filed as Exhibit 4.1 hereto, and is incorporated by reference herein, and the
Second Amendment, which is filed as Exhibit 4.2 hereto and is incorporated
herein by reference.

Item 9.01.        Financial Statements and Exhibits.

         (c)      Exhibits.

         The following exhibits are filed as part of this report:

Exhibit No.           Description
-----------           -----------

Exhibit 4.1           Amendment No. 1 to the Rights Agreement, dated as of
                      February 9, 2005, between PacifiCare Health Systems, Inc.,
                      Mellon Investor Services, LLC, and Computershare Investor
                      Services, LLC.

Exhibit 4.2           Amendment No. 2 to the Rights Agreement, dated as of
                      July 6, 2005, between PacifiCare Health Systems, Inc. and
                      Computershare Investor Services, LLC, as rights agent.

<PAGE>

                                  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 hereunto duly authorized.


                                     PACIFICARE HEALTH SYSTEMS, INC.


Date:    July 12, 2005               By:  /s/ Peter Reynolds
                                          ----------------------------------
                                     Name:   Peter Reynolds
                                     Title:  Senior Vice President, Finance;
                                             Corporate Controller


<PAGE>

                                 EXHIBIT INDEX

Exhibit No.           Description
-----------           -----------

Exhibit 4.1           Amendment No. 1 to the Rights Agreement, dated as of
                      February 9, 2005, between PacifiCare Health Systems, Inc.,
                      Mellon Investor Services, LLC, and Computershare Investor
                      Services, LLC.

Exhibit 4.2           Amendment No. 2 to the Rights Agreement, dated as of
                      July 6, 2005, between PacifiCare Health Systems, Inc. and
                      Computershare Investor Services, LLC, as rights agent.
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{"company-data": {"conformed-name": "PACIFICARE HEALTH SYSTEMS INC /DE/", "cik": "0001027974", "assigned-sic": "6324", "irs-number": "954591529", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-31700", "film-number": "05950295"}, "business-address": {"street1": "5995 PLAZA DRIVE", "city": "CYPRESS", "state": "CA", "zip": "90630-5028", "phone": "714-952-1121"}, "mail-address": {"street1": "5995 PLAZA DRIVE", "city": "CYPRESS", "state": "CA", "zip": "90630-5028"}, "former-company": {"former-conformed-name": "N T HOLDINGS INC", "date-changed": "19961204"}}
UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

                               _________________

                                    FORM 8-K

                                 CURRENT REPORT
                     Pursuant to Section 13 or 15(d) of the
                        Securities Exchange Act of 1934

 Date of Report (Date of Earliest Event Reported): July 12, 2005 (July 6, 2005)

                         PacifiCare Health Systems, Inc
             (Exact Name of Registrant as Specified in its Charter)

          Delaware                      001-31700                 95-4591529
(State or Other Jurisdiction         (Commission File           (IRS Employer
      of Incorporation)                  Number)             Identification No.)

           5995 Plaza Dr. Cyprus, California                  90630-5028
       (Address of Principal Executive Offices)               (Zip Code)

                                 (714) 952-1121
              (Registrant's telephone number, including area code)

         Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions:

|_|    Written communications pursuant to Rule 425 under the Securities Act
       (17 CFR 230.425)

|_|    Soliciting material pursuant to Rule 14a-12 under the Exchange Act
       (17 CFR 240.14a-12)

|_|    Pre-commencement communications pursuant to Rule 14d-2(b)
       under the Exchange Act (17 CFR 240.14d-2(b))

|_|    Pre-commencement communications pursuant to Rule 13e-4(c)
       under the Exchange Act (17 CFR 240.13e-4(c))

Item 3.03.        Material Modification to Rights of Security Holders.

         PacifiCare Health Systems, Inc., a Delaware corporation (the
"Company"), entered into two amendments to its Rights Agreement, dated as of
November 19, 1999, between the Company and ChaseMellon Shareholder Services,
L.L.C. (predecessor to Mellon Investor Services, LLC ("Mellon")), as rights
agent (the "Rights Agreement"). Unless otherwise noted, capitalized terms used
but not defined herein shall have the meaning assigned thereto in the Rights
Agreement. The initial amendment was entered into as of February 9, 2005 by
the Company, Mellon and Computershare Investor Services, LLC ("Computershare")
(the "First Amendment") and the second amendment was entered into as of July
6, 2005 by the Company and Computershare (the "Second Amendment").

         The First Amendment removed Mellon as rights agent and appointed
Computershare as successor Rights Agent. The Second Amendment was authorized
by the Board of Directors of the Company in connection with the Agreement and
Plan of Merger, dated as of July 6, 2005 (the "Merger Agreement"), with the
Company, UnitedHealth Group Incorporated, a Minnesota corporation ("Parent")
and Point Acquisition LLC, a limited liability company organized under the
laws of the State of Delaware. The Second Amendment provides that (i) neither
Parent nor any of its Subsidiaries, Affiliates or Associates shall be deemed
to be an Acquiring Person or a Principal Party by virtue of the execution of
the Merger Agreement or the consummation of the transactions contemplated
thereby, (ii) none of a Shares Acquisition Date, Distribution Date or
Transaction shall be deemed to have occurred by reason of the execution of the
Merger Agreement or consummation of the transactions contemplated thereby,
(iii) the Final Expiration Date of the Rights Agreement shall occur on the
earlier of the Close of Business on November 19, 2009 or immediately prior to
the Effective Time (as defined in the Merger Agreement) and (iv) the Rights
Agreement and the Rights established thereby will terminate immediately prior
to the Effective Time (as defined in the Merger Agreement).

         The Rights Agreement, including the form of the Rights Certificate,
is filed as an exhibit to the Registration Statement on Form 8-K filed with
the Securities and Exchange Commission on November 19, 1999 and is
incorporated herein by reference. The foregoing descriptions of the First
Amendment and the Second Amendment do not purport to be complete and are
qualified in their entirety by reference to the First Amendment, which is
filed as Exhibit 4.1 hereto, and is incorporated by reference herein, and the
Second Amendment, which is filed as Exhibit 4.2 hereto and is incorporated
herein by reference.

Item 9.01.        Financial Statements and Exhibits.

         (c)      Exhibits.

         The following exhibits are filed as part of this report:

Exhibit No.           Description
-----------           -----------

Exhibit 4.1           Amendment No. 1 to the Rights Agreement, dated as of
                      February 9, 2005, between PacifiCare Health Systems, Inc.,
                      Mellon Investor Services, LLC, and Computershare Investor
                      Services, LLC.

Exhibit 4.2           Amendment No. 2 to the Rights Agreement, dated as of
                      July 6, 2005, between PacifiCare Health Systems, Inc. and
                      Computershare Investor Services, LLC, as rights agent.
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 hereunto duly authorized.

                                     PACIFICARE HEALTH SYSTEMS, INC.

Date:    July 12, 2005               By:  /s/ Peter Reynolds
                                          ----------------------------------
                                     Name:   Peter Reynolds
                                     Title:  Senior Vice President, Finance;
                                             Corporate Controller
EXHIBIT INDEX

Exhibit No.           Description
-----------           -----------

Exhibit 4.1           Amendment No. 1 to the Rights Agreement, dated as of
                      February 9, 2005, between PacifiCare Health Systems, Inc.,
                      Mellon Investor Services, LLC, and Computershare Investor
                      Services, LLC.

Exhibit 4.2           Amendment No. 2 to the Rights Agreement, dated as of
                      July 6, 2005, between PacifiCare Health Systems, Inc. and
                      Computershare Investor Services, LLC, as rights agent.