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                                                                     EXHIBIT 4.3

                                 FIRST AMENDMENT
                                       TO
               AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT

         This First Amendment to Amended and Restated Registration Rights
Agreement (this "Amendment"), dated as of May 17, 2002, is made by and among Oil
States International, Inc., a Delaware corporation ("OSI") and the Holders of
Registrable Securities set forth on the signature page hereto (the "Amending
Holders").

         WHEREAS, reference is made to that certain Amended and Restated
Registration Rights Agreement by and among OSI, HWC, Sooner and each of the
holders of OSI Common Stock, HWC Common Stock and Sooner Common Stock listed on
the signature pages thereto (the "Amended and Restated Registration Rights
Agreement"); and

         WHEREAS, OSI and the Amending Holders desire to amend the Amended and
Restated Registration Rights Agreement in accordance with the provisions of
Section 9.3 thereof; and

         WHEREAS, the Amending Holders hold in the aggregate greater than 50% of
the Registrable Securities; and

         WHEREAS, capitalized terms that are used but not defined herein shall
have the meanings set forth in the Amended and Restated Registration Rights
Agreement;

         NOW, THEREFORE, for and in consideration of the mutual benefits to be
derived from this Amendment, and intending to be legally bound hereby, the
parties hereto hereby agree as follows:

         Section 1. AMENDMENTS TO AMENDED AND RESTATED REGISTRATION RIGHTS
AGREEMENT. The Amended and Restated Registration Rights Agreement is hereby
amended as follows:

                  (a) Section 3(a) is amended by deleting it in its entirety and
         inserting the following in replacement therefor:

                  "If OSI proposes to file, or has filed, a registration
                  statement under the Securities Act, including a Demand
                  Registration, with respect to an offering of OSI Common Stock
                  for cash by OSI for its own account or for the account of any
                  of its equity holders (other than (i) a registration statement
                  on Form S-4 or S-8 or any substitute form that may be adopted
                  by the SEC, (ii) any registration statement filed in
                  connection with an exchange offer or offering of securities
                  solely to OSI's existing security holders, (iii) any
                  registration statement filed in connection with an exchange
                  offer or offering of securities to holders of Exchangeable
                  Shares (the "PTI Registration Statement"), or (iv) any
                  "universal shelf" registration statement on Form S-3 or any
                  substitute form that may be adopted by the SEC that
                  contemplates the offering and sale by OSI of more than one
                  type of security on a delayed or continuous basis pursuant to
                  Rule 415 (or any successor rule) under the Securities Act, but
                  only if each of the Amending Holders has waived its right to
                  participate in any offering of Registrable Securities pursuant
                  to such registration statement), then OSI shall, at its
                  option, either (i) give written notice of such proposed filing
                  to the Holders of the Registrable Securities no later than 7
                  days before the anticipated
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                  initial filing date or (ii) give written notice of the filing
                  of such registration statement to the Holders of the
                  Registrable Securities no later than 7 days before the
                  anticipated effectiveness date of such registration statement,
                  and such notice shall offer such Holders the opportunity to
                  register such number of Registrable Securities as each such
                  Holder may request (a "Piggyback Registration"). On or before
                  the 7th day following the receipt of such notice by the
                  Holders, any Holder wishing to include any or all of its
                  Registrable Securities in such registration statement shall
                  give written notice to OSI stating the name of such Holder and
                  the amount of such Holder's Registrable Securities to be
                  included in such registration statement. Subject to Section
                  3(b), OSI shall include in each such Piggyback Registration
                  all Registrable Securities requested to be included in the
                  registration for such offering and shall, in the case of a
                  filed registration statement, prepare and file a pre-effective
                  amendment to such registration statement providing for the
                  inclusion of such Registrable Securities; provided, however,
                  that OSI may at any time withdraw or cease proceeding with
                  such registration without the consent of any Holder of
                  Registrable Securities, notwithstanding the request of any
                  such Holder to participate therein in accordance with this
                  provision, if OSI determines in its sole discretion that such
                  action is in the best interests of OSI and its stockholders
                  (for this purpose, the interests of the Holders shall not be
                  considered). Each Holder of Registrable Securities shall be
                  permitted to withdraw all or part of such Holder's Registrable
                  Securities from a Piggyback Registration at any time prior to
                  the effective date thereof."

                  (b) The second sentence of Section 9.3 is amended by deleting
         it in its entirety and inserting the following in replacement therefor:

                  "This Agreement may not be amended or supplemented at any
                  time, except by an instrument in writing signed by OSI and on
                  behalf of the Holders of 50% or more of the Registrable
                  Securities."

                  (c) The first paragraph of Section 9.5 is amended by deleting
         it in its entirety and inserting the following in replacement therefor:

                  "All notices and other communications hereunder shall be in
                  writing and (i) if to be delivered to OSI, HWC or Sooner,
                  shall be delivered in person, by overnight courier, by
                  facsimile (with confirmation of receipt) or by registered or
                  certified mail (postage prepaid, return receipt requested) and
                  shall be deemed effective and received only upon and as of the
                  date of actual receipt by OSI, HWC or Sooner, as the case may
                  be (except that receipt on any date after 5:00 p.m. Central
                  Standard Time shall be deemed received on the next Business
                  Day), and (ii) if to be delivered to a Holder, shall be
                  delivered in person, by overnight courier, by registered or
                  certified mail (postage prepaid, return receipt requested) or
                  by any other means of delivery and shall be deemed effective
                  and received (A) if given in person, on the date of actual
                  receipt by such Holder, (B) if given by overnight courier, on
                  the next Business Day immediately following the day on which
                  such notice is delivered to a reputable overnight courier
                  service, (C) if given by registered or certified mail, on the
                  third Business Day immediately following the day on which such
                  notice is deposited with

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                  a United States post office or (D) if given by any other
                  means, on the date on which such Holder acknowledges in
                  writing the receipt of such notice by such other means, in
                  each case to the respective parties as follows:"

         Section 2. MISCELLANEOUS.

                  (a) Counterparts. This Amendment may be executed in one or
         more counterparts, all of which shall be considered one and the same
         agreement, and shall become effective when one or more counterparts
         have been signed by each of the parties hereto and delivered (including
         by facsimile) to the other parties hereto.

                  (b) Incorporation. The provisions of Sections 9.3, 9.4, 9.5,
         9.6, 9.7, 9.9, 9.10 and 9.11 of the Amended and Restated Registration
         Rights Agreement are hereby incorporated herein and shall be deemed to
         include and/or apply to this Amendment, as appropriate.

                  (c) Ratification. Except as amended hereby, the Amended and
         Restated Registration Rights Agreement shall remain in full force and
         effect as previously executed by the parties, and the parties hereby
         ratify the Amended and Restated Registration Rights Agreement as
         amended hereby.

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         IN WITNESS WHEREOF, each of the undersigned, intending to be legally
bound, has caused this Amendment to be duly executed and delivered on the date
first set forth above.

                                OIL STATES INTERNATIONAL, INC.



                                By: /s/ Robert W. Hampton
                                   ---------------------------------------------
                                Name:  Robert W. Hampton
                                Title: Vice President - Finance and
                                       Accounting and Secretary


                                SCF III, L.P.

                                By: SCF II, L.P.,
                                    its General Partner

                                    By: L.E. Simmons & Associates, Incorporated,
                                        its General Partner



                                        By: /s/ Anthony DeLuca
                                           -------------------------------------
                                        Name:  Anthony DeLuca
                                        Title: Managing Director


                                SCF IV, L.P.

                                By: SCF-IV, G.P., Limited Partnership,
                                    its General Partner

                                    By: L.E. Simmons & Associates, Incorporated,
                                        its General Partner



                                        By: /s/ Anthony DeLuca
                                           -------------------------------------
                                        Name:  Anthony DeLuca
                                        Title: Managing Director

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