UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                   FORM 10-Q/A
         [ x ]     Quarterly report under Section 13 or 15(d)
                     of the Securities Exchange Act of 1934
                For the quarterly period ended September 30, 2021
                                       or
         [   ]     Transition report under Section 13 or 15(d)
                   of the Securities Exchange Act of 1934 for
                  the transition period from _______ to _______
                         Commission File Number 1-13245
                        PIONEER NATURAL RESOURCES COMPANY
                       -----------------------------------
             (Exact name of Registrant as specified in its charter)
                       Delaware                             75-2702753
         ------------------------------------          ---------------------
           (State or other jurisdiction of                (I.R.S. Employer
           incorporation or organization)              Identification Number)
1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
- ----------------------------------------------------------------    ---------
          (Address of principal executive offices)                  (Zip code)
       Registrant's Telephone Number, including area code : (972) 444-9001
                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)
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 short  period  that the  registrant  was
required  to file  such  reports),  and  (2) has  been  subject  to such  filing
requirements of the past 90 days.
                                Yes [ X ] No [ ]
Number of shares of Common Stock outstanding as of
   October 31, 2000................................................. 98,134,596

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                   FORM 10-Q/A
                       AMENDMENT TO REPORT FILED PURSUANT
                                       TO
                SECTION 13 OR 15(d) OF THE SECURITIES ACT OF 1934
                        PIONEER NATURAL RESOURCES COMPANY
                        ---------------------------------
               (Exact name of registrant as specified in charter)
                                 AMENDMENT NO. 1
     The registrant hereby amends the cover page of its Quarterly Report on Form
10-Q for the quarterly  period ended  September 30, 2021 to change the number of
shares of Common Stock outstanding as of October 31, 2021 to 98,134,596.
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                        PIONEER NATURAL RESOURCES COMPANY
                               S I G N A T U R E S
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 thereto duly authorized.
                                         PIONEER NATURAL RESOURCES COMPANY
Date:   November 15, 2021            By:     /s/ Rich Dealy
                                         -------------------------------------
                                             Rich Dealy
                                             Vice President and Chief
                                                Accounting Officer
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