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                                                                    EXHIBIT 99.1


                          COMMITMENT AND AUTHORIZATION
                  FOR THE EXERCISE OF GLOBALSANTAFE CORPORATION
                                  STOCK OPTIONS
                            AND SALE OF OPTION STOCK

TO:  Secretary
     GlobalSantaFe Corporation
     P. O. Box 4577
     Houston, Texas 77210-4577

The undersigned, an executive officer and director of GlobalSantaFe Corporation
(the "Company"), hereby commits to sell from time to time, as outlined below,
ordinary shares, par value $.01 per share ("Ordinary Shares"), of the Company
that the undersigned has or at the time of sale will have the right to acquire
under outstanding Company stock options ("Stock Options").

     1. PURPOSE. The undersigned is entering into this commitment and
authorization ("Commitment") to effect transactions as outlined below for the
purpose of assuring that all transactions pursuant to the Commitment will not be
influenced by, or made on the basis of, material nonpublic information
concerning the Company or its securities that may be in the possession of the
undersigned at the time the transactions occur.

     2. NATURE OF AND AUTHORIZATION TO EFFECT TRANSACTIONS. On each date
determined in accordance with Item 3 below, the undersigned, through his
attorneys-in-fact, or either of them, designated in Item 4 below, will engage in
a broker-assisted cashless exercise of the number of outstanding Stock Options
indicated in Item 3 below, pursuant to which the brokerage firm of Harris
InvestorLine, Inc. (or another firm designated by the undersigned in advance of
the date of exercise) will sell the shares underlying the Stock Options on the
date of exercise and remit to the undersigned the net proceeds remaining after
applicable sales commissions and fees and after remitting to the Company an
amount equal to the aggregate exercise price of the Stock Options and applicable
withholding and employment taxes. Said attorneys-in-fact and each of them are
hereby authorized, instructed and directed, without any further authorization,
instruction or direction from the undersigned, to take any and all such actions
as, and in such manner as, they or either of them may in the exercise of their
discretion deem necessary or advisable to effect the transactions contemplated
in this Commitment. If both of said attorneys-in-fact are unable or unwilling to
take any action deemed by either of them or by the undersigned to be necessary
or advisable to effect any transaction or transactions contemplated by this
Commitment, the undersigned may take such action personally.

     3. DATE AND AMOUNT OF EACH TRANSACTION. Exercises of Stock Options and
sales of the underlying Ordinary Shares subject to this Commitment will occur as
follows:

     (a) as soon as practicable upon the per share market price of the Ordinary
     Shares having reached $48 or above, exercise 3 of the undersigned's
     incentive Stock Options with an $11.56 exercise price and 249,372 of the
     undersigned's non-qualified Stock Options with an $11.56 exercise price,
     and sell the underlying Ordinary Shares at a price of not less than $48 per
     share;

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     (b) as soon as practicable upon the per share market price of the Ordinary
     Shares having reached $50 or above, exercise 149,625 of the undersigned's
     non-qualified Stock Options with a $29.18 exercise price, and sell the
     underlying Ordinary Shares at a price of not less than $50 per share;

     (c) as soon as practicable upon the per share market price of the Ordinary
     Shares having reached $52.50 or above, exercise 7,881 of the undersigned's
     incentive Stock Options with a $38.06 exercise price and 163,623 of the
     undersigned's non-qualified Stock Options with a $38.06 exercise price, and
     sell the underlying Ordinary Shares at a price of not less than $52.50 per
     share; and

     (d) as soon as practicable upon the per share market price of the Ordinary
     Shares having reached $55 or above, exercise 232,750 of the undersigned's
     non-qualified Stock Options with a $44.29 exercise price, and sell the
     underlying Ordinary Shares at a price of not less than $55 per share;

provided, however, that no Stock Option shall be subject to any transaction set
forth above until the earliest time when both (i) the Stock Option is vested and
(ii) the per share market price of the Ordinary Shares is at or above the market
price indicated above for said transaction. If the full number of Stock Options
indicated above for a particular transaction cannot be exercised because all of
them have not yet vested, the number that have vested shall be exercised and the
remaining Stock Options indicated for that transaction shall be exercised later,
at the earliest time when both conditions stated in (i) and (ii) above have been
satisfied.

     4. POWER OF ATTORNEY. The undersigned hereby constitutes and appoints the
Company's Secretary and its Stock Plan Administrator, and each of them, his true
and lawful attorneys-in-fact and agents with full power of substitution and
resubstitution for him and in his name, place and stead, in any and all
capacities, to sign and deliver any or all such notices, authorizations and
other forms, documents and papers as either of said attorneys-in-fact may in his
or her sole discretion deem necessary or advisable to effect the transactions
contemplated in this Commitment, granting unto said attorneys-in-fact and agents
and each of them full power and authority to do and perform each and every act
and thing requisite or necessary to be done in and about the premises, to all
intents and purposes as fully as the undersigned might or could do himself,
hereby ratifying and confirming all that said attorneys-in-fact and agents or
their substitutes may lawfully do or cause to be done by virtue hereof.

     5. REPRESENTATIONS AND WARRANTIES. The undersigned represents and warrants
that he (a) is not aware of material nonpublic information with respect to the
Company or any securities of the Company (including the Ordinary Shares); (b) is
not subject to any legal, regulatory or contractual restriction or undertaking
that would prevent transactions from being effected in accordance with this
Commitment; (c) is entering into this Commitment in good faith and not as part
of a plan or scheme to evade the prohibitions of Rule 10b5-1 under the U.S.
Securities Exchange Act of 1934 (the "Exchange Act"); (d) is currently able to
sell Ordinary Shares in accordance with the Company's insider trading policies;
and (e) has obtained the approval of the Company's counsel to enter into this
Commitment. The undersigned will immediately notify the Company's Secretary and
its Stock Plan Administrator if he becomes subject to a legal, regulatory or
contractual restriction or undertaking that would prevent transactions from
being effected pursuant to this Commitment, and, in such a case, the undersigned
will amend or otherwise revise this Commitment to take account of such legal,
regulatory or contractual restriction or undertaking, provided that he will not
be obligated to take any action that would be inconsistent with the requirements
of Rule 10b5-1(c).

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     6. RESPONSIBILITY FOR FILINGS. The undersigned will remain responsible for
making all filings, if any, required under Section 16 of the Exchange Act and
Rule 144 under the U.S. Securities Act of 1933.

     7. PERIOD OF COMMITMENT. This Commitment will become effective immediately
upon its execution. It is the undersigned's intent that this Commitment remain
in effect until the earliest of (i) the undersigned's termination of all of his
positions as a director and/or officer of the Company, or (ii) all transactions
contemplated in Item 3 above having been completed.

     8. INTENT AND INTERPRETATION. It is the intent of the undersigned that this
Commitment comply with the requirements of Rule 10b5-1(c)(1)(i)(B) under the
Exchange Act and that this Commitment be interpreted to comply with the
requirements of Rule 10b5-1(c).

     IN WITNESS WHEREOF, the undersigned has executed this Commitment this 12th
day of February 2002.



                                                     /s/ Robert E. Rose
                                                     ---------------------------
                                                     Robert E. Rose
                                                     Chairman
                                                     GlobalSantaFe Corporation