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                                   Exhibit 10


                      THE NEWHALL LAND AND FARMING COMPANY
                                 RETIREMENT PLAN
                                 AMENDMENT NO. 4

                  The Newhall Land and Farming Company Retirement Plan (the
"Plan"), as restated in its entirety effective January 1, 1989, and subsequently
amended, is hereby further amended, as follows:

         1.       Section 1.45 of the Plan is hereby amended, effective as of
January 1, 1997, by striking the last paragraph and inserting the following:

                  "Remuneration shall include any employer contribution under a
                  cash or deferred arrangement to the extent not included in
                  gross income under Code Section 402(g)(3) and any amount which
                  the employee would have received in cash but for an election
                  under a cafeteria plan (within the meaning of Code Sections
                  125).

                  "Notwithstanding the foregoing, for purposes of Section 15.01
                  (b), an Employee's Remuneration shall not exceed the
                  limitation amount contained in Section 1.10(b)."

         2.       Section 1.30 of the Plan is hereby amended in its entirety,
as of January 1, 1997, as follows:

                  "LEASED EMPLOYEE means any person, other than a common law
                  employee of an Affiliated Company, who pursuant to an
                  agreement between an Affiliated Company and any other person
                  ("leasing organization") has performed services for the
                  Affiliated Company (or for the Affiliated Company and related
                  persons determined in accordance with Section 414(n)(6) of the
                  Code) on a substantially full-time basis for a period of at
                  least one year (as determined in accordance with the
                  applicable provisions of the proposed Income Tax Regulations
                  section 1.414(n)-1(b)(10)), and such services are performed
                  under the primary direction or control of the Affiliated
                  Company."

         3.       Section 1.01 of the Plan is hereby amended in its entirety,
effective as of January 1, 2000, to read as follows:

                  "ACTUARIAL EQUIVALENT shall mean the determination of a
                  benefit having the same value as the benefit under the Plan
                  which it replaces. Determination of a Participant's vested
                  accrued benefit for purposes other than a lump sum payment
                  shall be based on an interest rate of six percent (6%) and
                  mortality specified in Table 18-a of the Society of Actuaries
                  1983 Exposure Draft on Development of the 1983 Group Annuity
                  Mortality Table ("GAM 83"); mortality rates used for
                  individual Participants shall be based on Table 18-a rates for
                  individuals one year younger. Notwithstanding the preceding
                  sentence, determining (i) whether the present value of a
                  Participant's accrued benefit exceeds $5,000 for purposes of
                  Section 7.05 and (ii) the amount of a lump sum benefit, shall
                  be calculated using


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                  whichever of the following yields the largest present value of
                  the vested accrued lump sum retirement benefit due an
                  Employee:

                  (a) The Applicable Interest Rate under Section 417(e) of the
                  Code for the second full calendar month before the date of
                  distribution, and the Applicable Mortality Table under Section
                  417(e) of the Code; or

                  (b) Eighty-eight percent (88%) of the average interest rate on
                  30-year Treasury securities for the third full calendar month
                  before the date of distribution, and the GAM 83 mortality
                  table blended 50% male and 50% female.

                  Notwithstanding any other provision of the Plan to the
                  contrary, the present value of the accrued lump sum retirement
                  benefit due an Employee who became a Participant prior to
                  January 1, 2000 shall not be less than the present value of
                  such Participant's vested accrued benefit as of December 31,
                  1999 utilizing an interest rate that is equal to nine percent
                  (9%) and mortality table specified above for purposes other
                  than a lump sum payment."

         4.       Section 7.04 of the Plan is hereby amended, effective as of
January 1, 1999, by adding the following paragraph:

                  "The Annuity Starting Date for a distribution in a form other
                  than a joint and survivor annuity may be less than 30 days
                  after receipt of the written explanation described above
                  provided: (a) the Participant has been provided with
                  information that clearly indicates that the Participant has at
                  least 30 days to consider whether to waive the joint and
                  survivor annuity and to elect (with spousal consent) a form of
                  distribution other than a joint and survivor annuity; (b) the
                  Participant is permitted to revoke any affirmative
                  distribution election at least until the annuity starting date
                  or, if later, at any time prior to the expiration of the 7-day
                  period that begins the day after the explanation of the joint
                  and survivor annuity is provided to the Participant; and (c)
                  the Annuity Starting Date is a date after the date that the
                  written explanation was provided to the Participant."

         5. Except as modified by this Amendment No. 4, all the terms and
provisions of the Plan, as previously amended, shall continue in full force
and effect.

                  IN WITNESS WHEREOF, The Newhall Land and Farming Company, has
caused this instrument to be executed on its behalf by its duly authorized
officer as of this 21st day of July, 1999.

                                The Newhall Land and Farming Company
                                (A California Limited Partnership)
                                By:   Newhall Management Limited Partnership,
                                      Managing General Partner
                                By:   Newhall Management Corporation,
                                      Managing General Partner

                                By:   / S / Trude Tsujimoto
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