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)        March 29, 2000
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                               UNOCAL CORPORATION
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             (Exact name of registrant as specified in its charter)



                                    Delaware
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                 (State or Other Jurisdiction of Incorporation)



    1-8483                                   95-3825062
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(Commission File Number)                (I.R.S. Employer Identification No.)



2141 Rosecrans Avenue, Suite 4000, El Segundo, California         90245
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(Address of Principal Executive Offices)                       (Zip Code)



                                 (310) 726-7600
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              (Registrant's Telephone Number, Including Area Code)

    1
Item 5.      Other Events.
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On March 29, 2000,  the United  States Court of Appeals for the Federal  Circuit
affirmed a judgement  of the U.S.  District  Court for the  Central  District of
California that upheld the validity of one of the company's  reformulated  motor
gasolines patents.

Following a 1997 trial in the  District  Court,  a jury had found the patent was
valid and that six defendant  companies had infringed the patent with respect to
1.19  billion  gallons,  or 29.1  percent of the total  California  reformulated
gasoline  manufactured by the six defendant companies between March 1, 1996, and
July 31,  1996.  The jury also  awarded  the  company  5-3/4 cents per gallon in
damages  for this  infringement.  The  jury's  award for the  five-month  period
totaled  approximately  $91 million at year-end  1999,  including  interest  and
attorney's fees.

The "393" patent (No.  5,288,393) was awarded to the company by the U.S.  Patent
and  Trademark  Office  on  Feb.  22,  1994,  for  new,  useful  and  nonobvious
compositions  of  traditional  automotive  gasolines that  substantially  reduce
unwanted tailpipe emissions using current refining technology.  The compositions
outlined in the patent involve  specifications of various parameters in gasoline
manufacturing,  including Reid Vapor Pressure,  olefin content,  and the T50 and
T90 distillation points.

A series of  additional  patents has been granted to the company since the "393"
patent. These patents were an outgrowth of the earlier research and supplemented
the claims of the earlier patent.  The patents may have  application  throughout
the United States,  not just California.  None of the patents require or exclude
the use of MTBE.

The company believes that its patents may offer a significant  potential revenue
stream.  With the  Court  of  Appeals  decision,  the  company  will now ask the
District  Court,  for an accounting by the  defendants of nationwide  infringing
gallons  manufactured by them for the period since Aug. 1, 1996, to the present,
multiplied by 5-3/4-cents per gallon.

  2
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.



                                                UNOCAL CORPORATION
                                                (Registrant)





Date:  March 31, 2000                        By:  /s/ JOE D. CECIL
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                                                Joe D. Cecil
                                                Vice President and Comptroller