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                                                                   EXHIBIT 10.1



                       STOCK OPTION AGREEMENT (DOUBLETREE)

        STOCK OPTION AGREEMENT, dated as of September 1, 1997 (the "Agreement"),
between DOUBLETREE CORPORATION., a Delaware corporation (the "Grantee"), and
PROMUS HOTEL CORPORATION, a Delaware corporation (the "Grantor").

        WHEREAS, the Grantee, Parent Holding Corp., a Delaware corporation
("Parent"), and the Grantor are entering into an Agreement and Plan of Merger,
dated as of the date hereof (the "Merger Agreement"), which provides, among
other things, for the merger (the "Doubletree Merger") of a subsidiary of Parent
with and into the Grantee and the merger (the "Promus Merger") of another
subsidiary of Parent with and into the Grantor, such that the Grantee and the
Grantor will become wholly-owned subsidiaries of Parent and the stockholders of
the Grantee and the Grantor will become stockholders of Parent (the Doubletree
Merger and the Promus Merger collectively, the "Mergers");

        WHEREAS, pursuant to a Stock Option Agreement dated as of the date
hereof between the Grantee and the Grantor, the Grantee has granted the Grantor
an option to acquire shares of common stock of the Grantee on terms that are
substantially similar to the terms of this Agreement (the "Promus Option");

        WHEREAS, as a condition and inducement to their willingness to enter
into the Merger Agreement and the Promus Option, the Grantee and Parent have
requested that the Grantor grant to the Grantee an option to purchase 9,929,485
shares of Common Stock, par value $0.10 per share, of the Grantor (the "Common
Stock"), upon the terms and subject to the conditions hereof; and

        WHEREAS, in order to induce the Grantee to enter into the Merger
Agreement and grant the Promus Option, the Grantor is willing to grant the
Grantee the requested option.

        NOW, THEREFORE, in consideration of the premises and the mutual
covenants and agreements set forth herein, the parties hereto agree as follows:

        1.     The Option; Exercise; Adjustments; Payment of Spread.

                (a) Contemporaneously herewith the Grantee, Parent and the
Grantor are entering into the Merger Agreement. Subject to the other terms and
conditions set forth herein, the Grantor hereby grants to the Grantee an
irrevocable option (the "Option") to purchase up to 9,929,485 (as adjusted as
provided herein) shares of Common Stock (together with the associated purchase
rights issued with respect thereto pursuant to the Rights Agreement dated as of
June 30, 1995 between the Grantor and Continental Stock Transfer & Trust Company
(the "Grantor Rights Plan")) (the "Shares") at a per share cash purchase price
equal to the lower of (i) $38.8125 per Share or (ii) the average closing sales
price of the Common Stock on the New York Stock Exchange Composite Tape (the
"NYSE Composite Tape") for the five consecutive trading days beginning on and
including the day that the Mergers are publicly announced (as adjusted as
provided herein) (such lower price being the "Purchase Price"). The Option may
be exercised by the Grantee, in whole or in part, at any time, or from time to
time, following the occurrence of 

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one of the events set forth in Section 2(c) hereof and prior to the termination
of the Option in accordance with the terms of this Agreement.

                (b) In the event the Grantee wishes to exercise the Option,
the Grantee shall send a written notice to the Grantor (the "Stock Exercise
Notice") specifying a date (subject to the HSR Act (as defined below)) not later
than 10 business days and not earlier than the next business day following the
date such notice is given for the closing of such purchase. In the event of any
change in the number of issued and outstanding shares of Common Stock by reason
of any stock dividend, stock split, split-up, reclassification,
recapitalization, merger or other change in the corporate or capital structure
of the Grantor (including the occurrence of a Distribution Date under the
Grantor Rights Plan), the number of Shares subject to this Option and the
purchase price per Share shall be appropriately adjusted to restore the Grantee
to its rights hereunder, including its right to purchase Shares representing
19.9% of the capital stock of the Grantor entitled to vote generally for the
election of the directors of the Grantor which is issued and outstanding
immediately prior to the exercise of the Option at an aggregate purchase price
equal to the Purchase Price multiplied by 9,929,485. In the event that any
additional shares of Common Stock are issued after the date of this Agreement
(other than pursuant to an event described in the preceding sentence), the
number of Shares subject to this Option shall be increased by 19.9% of the
number of the additional shares of Common Stock so issued (and such additional
Shares shall have a purchase price per share equal to the Purchase Price).

                (c) If at any time the Option is then exercisable pursuant to
the terms of Section 1(a) hereof, the Grantee may elect, in lieu of exercising
the Option to purchase Shares provided in Section 1(a) hereof, to send a written
notice to the Grantor (the "Cash Exercise Notice") specifying a date not later
than 20 business days and not earlier than 10 business days following the date
such notice is given on which date the Grantor shall pay to the Grantee an
amount in cash equal to the Spread (as hereinafter defined) multiplied by all or
such portion of the Shares subject to the Option as Grantee shall specify. As
used herein "Spread" shall mean the excess, if any, over the Purchase Price of
the higher of (x) if applicable, the highest price per share of Common Stock
(including any brokerage commissions, transfer taxes and soliciting dealers'
fees) paid by any person in an Alternative Transaction (as defined in clause
(i), (ii) or (iii) of Section 7.3(e) of the Merger Agreement) (the "Alternative
Purchase Price") or (y) the closing sales price of the shares of Common Stock on
the NYSE Composite Tape on the last trading day immediately prior to the date of
the Cash Exercise Notice (the "Closing Price"). If the Alternative Purchase
Price includes any property other than cash, the Alternative Purchase Price
shall be the sum of (i) the fixed cash amount, if any, included in the
Alternative Purchase Price plus (ii) the fair market value of such other
property. If such other property consists of securities with an existing public
trading market, the average of the closing sales prices (or the average of the
closing bid and asked prices if closing sales prices are unavailable) for such
securities in their principal public trading market on the five trading days
ending five days prior to the date of the Cash Exercise Notice shall be deemed
to equal the fair market value of such property. If such other property consists
of something other than cash or securities with an existing public trading
market and, as of the payment date for the Spread, agreement on the value of
such other property has not been reached, the Alternative Purchase Price shall
be deemed to equal the Closing Price. Upon exercise of the Grantee's right to
receive cash pursuant to this Section 1(c) and the payment of such cash to the
Grantee, the obligations of the Grantor to deliver Shares pursuant to Section 3


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shall be terminated with respect to such number of Shares for which the Grantee
shall have elected to be paid the Spread.

        2.     Conditions to Delivery of Shares. The Grantor's obligation to 
deliver Shares upon exercise of the Option is subject only to the conditions
that:

                (a) No preliminary or permanent injunction or other order
issued by any federal or state court of competent jurisdiction in the United
States prohibiting the delivery of the Shares shall be in effect; and

                (b) Any applicable waiting periods under the Hart-Scott-Rodino
Antitrust Improvements Act of 1976 (the "HSR Act") shall have expired or been
terminated and all other consents, approvals, orders, notifications or
authorizations, the failure of which to obtain or make would have the effect of
making the issuance of the Shares illegal (collectively, the "Regulatory
Approvals") shall have been obtained or made; and

                (c) (i) a proposal for an Alternative Transaction (as defined in
the Merger Agreement) involving the Grantor shall have been publicly announced
prior to the time the Merger Agreement is terminated pursuant to the terms
thereof (the "Merger Termination Date") and one or more of the following events
shall have occurred on or after the time of the making of such proposal: (A) the
requisite vote of the stockholders of the Grantor in favor of adoption and
approval of the Merger Agreement shall not have been obtained at the Promus
Stockholders' Meeting (as defined in the Merger Agreement) or any adjournment or
postponement thereof; (B) the Board of Directors of the Grantor shall have
withdrawn or modified its recommendation of the Merger Agreement or the Promus
Merger or failed to confirm its recommendation of the Merger Agreement or the
Promus Merger to the stockholders of the Grantor within ten business days after
a written request by the Grantee to do so; (C) the Board of Directors of the
Grantor shall have recommended to the stockholders of the Grantor an Alternative
Transaction (as defined in the Merger Agreement); (D) a tender offer or exchange
offer for 20% or more of the outstanding shares of Grantor Common Stock shall
have been commenced (other than by the Grantee or an affiliate of the Grantee)
and the Board of Directors of the Grantor shall have recommended that the
stockholders of the Grantor tender their shares in such tender or exchange
offer; or (E) for any reason Grantor shall have failed to call and hold the
Promus Stockholders' Meeting (as defined in the Merger Agreement) by the Outside
Date (as defined in the Merger Agreement; provided, however, that the Option may
not be exercised if the Grantee is in material breach of any of its material
representations, warranties, covenants or agreements contained in this Agreement
or in the Merger Agreement; or (ii) the Merger Agreement shall have been
terminated by the Grantor pursuant to Section 7.1(g) of the Merger Agreement.

        3.     The Closing.

                (a) Any closing hereunder shall take place on the date specified
by the Grantee in its Stock Exercise Notice or Cash Exercise Notice, as the case
may be, at 8:00 A.M., local time, at the offices of Latham & Watkins, 633 West
Fifth Street, Suite 4000, Los Angeles, CA 90071, or, if the conditions set forth
in Section 2(a) or 2(b) have not then been satisfied, on 



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the second business day following the satisfaction of such conditions, or at
such other time and place as the parties hereto may agree (the "Closing Date").
On the Closing Date, (i) in the event of a closing pursuant to Section 1(b)
hereof, the Grantor will deliver to the Grantee a certificate or certificates,
duly endorsed (or accompanied by duly executed stock powers), representing the
Shares in the denominations designated by the Grantee in its Stock Exercise
Notice and the Grantee will purchase such Shares from the Grantor at the price
per Share equal to the Purchase Price or (ii) in the event of a closing pursuant
to Section 1(c) hereof, the Grantor will deliver to the Grantee cash in an
amount determined pursuant to Section 1(c) hereof. Any payment made by the
Grantee to the Grantor, or by the Grantor to the Grantee, pursuant to this
Agreement shall be made by certified or official bank check or by wire transfer
of federal funds to a bank designated by the party receiving such funds.

               (b) The certificates representing the Shares may bear an
appropriate legend relating to the fact that such Shares have not been
registered under the Securities Act of 1933, as amended (the "Securities Act").

        4.     Representations And Warranties of the Grantor. The Grantor 
represents and warrants to the Grantee that (a) the Grantor is a corporation
duly organized, validly existing and in good standing under the laws of the
State of Delaware and has the requisite corporate power and authority to enter
into and perform this Agreement; (b) the execution and delivery of this
Agreement by the Grantor and the consummation by it of the transactions
contemplated hereby have been duly authorized by the Board of Directors of the
Grantor and this Agreement has been duly executed and delivered by a duly
authorized officer of the Grantor and constitutes a valid and binding obligation
of the Grantor, enforceable in accordance with its terms, subject to bankruptcy,
insolvency, fraudulent transfer, reorganization, moratorium and similar laws of
general applicability relating to or affecting creditors' rights and to general
equity principles; (c) the Grantor has taken all necessary corporate action to
authorize and reserve the Shares issuable upon exercise of the Option and the
Shares, when issued and delivered by the Grantor upon exercise of the Option,
will be duly authorized, validly issued, fully paid and non-assessable and free
of preemptive rights; (d) except as otherwise required by the HSR Act and other
than any filings required under the blue sky laws of any states or by the New
York Stock Exchange, Inc. (the "NYSE"), the execution and delivery of this
Agreement by the Grantor and the issuance of Shares upon exercise of the Option
do not require the consent, waiver, approval or authorization of or any filing
with any person or public authority and will not violate, result in a breach of
or the acceleration of any obligation under, or constitute a default under, any
provision of any charter or by-law, indenture, mortgage, lien, lease, agreement,
contract, instrument, order, law, rule, regulation, judgment, ordinance, or
decree, or restriction by which the Grantor or any of its subsidiaries or any of
their respective properties or assets is bound; (e) no "fair price",
"moratorium", "control share acquisition" or other form of antitakeover statute
or regulation (including, without limitation, the restrictions on "business
combinations" set forth in Section 203 of the Delaware General Corporation Law)
is or shall be applicable to the acquisition of Shares pursuant to this
Agreement (and the Board of Directors of Grantor has taken all action to approve
the acquisition of the Shares to the extent necessary to avoid such application)
and (f) the Grantor has taken all corporate action necessary so that the grant
and any subsequent exercise of the Option by the Grantee will not result in the
separation or exercisability of rights under the Grantor Rights Plan.

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        5.     Representations and Warranties of the Grantee. The Grantee 
represents and warrants to the Grantor that (a) the execution and delivery of
this Agreement by the Grantee and the consummation by it of the transactions
contemplated hereby have been duly authorized by all necessary corporate action
on the part of the Grantee and this Agreement has been duly executed and
delivered by a duly authorized officer of the Grantee and will constitute a
valid and binding obligation of Grantee; and (b) the Grantee is acquiring the
Option after the Grantee has been afforded the opportunity to obtain, and has
obtained, sufficient information regarding the Grantor to make an informed
investment decision with respect to the Grantee's purchase of the Shares
issuable upon the exercise thereof, and, if and when the Grantee exercises the
Option, it will be acquiring the Shares issuable upon the exercise thereof for
its own account and not with a view to distribution or resale in any manner
which would be in violation of the Securities Act.

        6.     Listing of Shares; HSR Act Filings; Regulatory Approvals. Subject
to applicable law and the rules and regulations of the NYSE, the Grantor will
promptly file an application to list the Shares on the NYSE and will use its
best efforts to obtain approval of such listing and to file all necessary
filings by the Grantor under the HSR Act; provided, however, that if the Grantor
is unable to effect such listing on the NYSE by the Closing Date, the Grantor
will nevertheless be obligated to deliver the Shares upon the Closing Date. Each
of the parties hereto will use its best efforts to obtain consents of all third
parties and all Regulatory Approvals, if any, necessary to the consummation of
the transactions contemplated.

        7.     Repurchase of Shares; Sale of Shares. If a Change in Control 
Event has not occurred prior to the first anniversary date of the Merger
Termination Date, then beginning on such anniversary date, the Grantor shall
have the right to purchase (the "Repurchase Right") all, but not less than all,
of the Shares then beneficially owned by the Grantee or any of its affiliates at
a price per share equal to the greater of (i) the Purchase Price, or (ii) the
average of the closing sales prices for shares of Common Stock on the twenty
trading days ending five days prior to the date the Grantor gives written notice
of its intention to exercise the Repurchase Right. If the Grantor does not
exercise the Repurchase Right within thirty days following the first anniversary
of the Merger Termination Date, the Repurchase Right terminates. In the event
the Grantor wishes to exercise the Repurchase Right, the Grantor shall send a
written notice to the Grantee specifying a date (not later than 10 business days
and not earlier than the next business day following the date such notice is
given) for the closing of such purchase. For purposes of the Agreement, a
"Change in Control Event" shall be deemed to have occurred if (i) any person or
group has a acquired beneficial ownership of more than fifty percent (excluding
the Shares) of the outstanding shares of Common Stock or (ii) the Grantor shall
have entered into an agreement, including without limitation an agreement in
principle, providing for (x) a merger or other business combination involving
the Grantor in which the Grantor's stockholders do not own a majority of the
outstanding capital stock of the entity surviving such merger or business
combination immediately following such transaction or (y) the acquisition of 20%
or more of the assets of the Grantor and its subsidiaries, taken as a whole.

        8.      Registration Rights.

                (a) In the event that the Grantee shall desire to sell any of
the Shares within two years after the purchase of such Shares pursuant hereto,
and such sale requires, in the 



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opinion of counsel to the Grantee, which opinion shall be reasonably
satisfactory to the Grantor and its counsel, registration of such Shares under
the Securities Act, the Grantor will cooperate with the Grantee and any
underwriters in registering such Shares for resale, including, without
limitation, promptly filing a registration statement which complies with the
requirements of applicable federal and state securities laws, entering into an
underwriting agreement with such underwriters upon such terms and conditions as
are customarily contained in underwriting agreements with respect to secondary
distributions; provided that the Grantor shall not be required to have declared
effective more than two registration statements hereunder and shall be entitled
to delay the filing or effectiveness of any registration statement for up to 120
days if the offering would, in the judgment of the Board of Directors of the
Grantor, require premature disclosure of any material corporate development or
otherwise interfere with or adversely affect any pending or proposed offering of
securities of the Grantor or any other material transaction involving the
Grantor.

                (b) If the Common Stock is registered pursuant to the
provisions of this Section 8, the Grantor agrees (i) to furnish copies of the
registration statement and the prospectus relating to the Shares covered thereby
in such numbers as the Grantee may from time to time reasonably request and (ii)
if any event shall occur as a result of which it becomes necessary to amend or
supplement any registration statement or prospectus, to prepare and file under
the applicable securities laws such amendments and supplements as may be
necessary to keep effective for at least 90 days a prospectus covering the
Common Stock meeting the requirements of such securities laws, and to furnish
the Grantee such numbers of copies of the registration statement and prospectus
as amended or supplemented as may reasonably be requested. The Grantor shall
bear the cost of the registration, including, but not limited to, all
registration and filing fees, printing expenses, and fees and disbursements of
counsel and accountants for the Grantor, except that the Grantee shall pay the
fees and disbursements of its counsel, the underwriting fees and selling
commissions applicable to the shares of Common Stock sold by the Grantee. The
Grantor shall indemnify and hold harmless Grantee, its affiliates and its
officers, directors and controlling persons from and against any and all losses,
claims, damages, liabilities and expenses arising out of or based upon any
statements contained or incorporated by reference in, and omissions or alleged
omissions from, each registration statement filed pursuant to this paragraph;
provided, however, that this provision does not apply to any loss, liability,
claim, damage or expense to the extent it arises out of any untrue statement or
omission made in reliance upon and in conformity with written information
furnished to the Grantor by the Grantee, its affiliates and its officers
expressly for use in any registration statement (or any amendment thereto) or
any preliminary prospectus filed pursuant to this paragraph. The Grantor shall
also indemnify and hold harmless each underwriter and each person who controls
any underwriter within the meaning of either the Securities Act or the
Securities Exchange Act of 1934, as amended, against any and all losses, claims,
damages, liabilities and expenses arising out of or based upon any statements
contained or incorporated by reference in, and omissions or alleged omissions
from, each registration statement filed pursuant to this paragraph; provided,
however, that this provision does not apply to any loss, liability, claim,
damage or expense to the extent it arises out of any untrue statement or
omission made in reliance upon and in conformity with written information
furnished to the Grantor by the underwriters expressly for use in any



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registration statement (or any amendment thereto) or any preliminary prospectus
filed pursuant to this paragraph.

        9.      Profit Limitation.

                (a) Notwithstanding any other provision of this Agreement, in no
event shall the Grantee's Total Profit (as hereinafter defined) exceed $65
million and, if it does exceed such amount, the Grantee, at its sole election,
shall, within five business days, either (a) deliver to the Grantor for
cancellation Shares (valued, for the purposes of this Section 9(a), at the
average closing sales price of the Common Stock on the NYSE Composite Tape for
the twenty consecutive trading days preceding the day on which the Grantee's
Total Profit exceeds $65 million) previously purchased by the Grantee, (b) pay
cash or other consideration to the Grantor or (c) undertake any combination
thereof, so that the Grantee's Total Profit shall not exceed $65 million after
taking into account the foregoing actions.

                (b) As used herein, the term "Total Profit" shall mean the
aggregate amount (before taxes) of the following: (i) the amount of cash
received by the Grantee pursuant to Section 7.3(c) of the Merger Agreement and
Section 1(c) hereof, (ii)(x) the net cash amount received by the Grantee
pursuant to the Grantor's repurchase of Shares pursuant to Section 7 hereof,
less (y) the Grantee's purchase price for such Shares, and (iii)(x) the amount
received by the Grantee pursuant to the sale of Shares (or any other securities
into which such Shares are converted or exchanged), less (y) the Grantee's
purchase price for such Shares.

        10.     Expenses. Each party hereto shall pay its own expenses incurred 
in connection with this Agreement, except as otherwise specifically provided
herein.

        11.     Specific Performance. The Grantor acknowledges that if the 
Grantor fails to perform any of its obligations under this Agreement immediate
and irreparable harm or injury would be caused to the Grantee for which money
damages would not be an adequate remedy. In such event, the Grantor agrees that
the Grantee shall have the right, in addition to any other rights it may have,
to specific performance of this Agreement. Accordingly, if the Grantee should
institute an action or proceeding seeking specific enforcement of the provisions
hereof, the Grantor hereby waives the claim or defense that the Grantee has an
adequate remedy at law and hereby agrees not to assert in any such action or
proceeding the claim or defense that such a remedy at law exists. The Grantor
further agrees to waive any requirements for the securing or posting of any bond
in connection with obtaining any such equitable relief.

        12.     Notice. All notices, requests, demands and other communications
hereunder shall be deemed to have been duly given and made if in writing and if
served by personal delivery upon the party for whom it is intended or delivered
by registered or certified mail, return receipt requested, or if sent by
facsimile transmission, upon receipt of oral confirmation that such transmission
has been received, to the person at the address set forth below, or such other
address as may be designated in writing hereafter, in the same manner, by such
person:

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                           If to the Grantee:

                           Doubletree Corporation
                           410 North 44th Street, Suite 700
                           Phoenix, AZ  85008
                           Attn:  Richard M. Kelleher
                           Telecopy: (602) 220-6753

                           With a copy to:

                           Dewey Ballantine
                           1301 Avenue of the Americas
                           New York, NY 10019-6092
                           Attn:  William J. Phillips, Esq.
                           Telecopy: (212) 295-6333

                           If to the Grantor:

                           Promus Hotel Corporation
                           755 Crossover Lane
                           Memphis, TN  38117
                           Attn:  Raymond E. Schultz
                           Telecopy: (901) 374-5636

                           With a copy to:

                           Latham & Watkins
                           633 West Fifth Street, Suite 4000
                           Los Angeles, California 90071-2007
                           Attn: John M. Newell, Esq.
                           Telecopy: (213) 891-8763

        13.    Parties in Interest. This Agreement shall inure to the benefit of
and be binding upon the parties named herein and their respective permitted
successors and assigns; provided, however, that such successor in interest or
assigns shall agree to be bound by the provisions of this Agreement. Except as
set forth in Section 8, nothing in this Agreement, express or implied, is
intended to confer upon any person other than the Grantor or the Grantee, or
their successors or assigns, any rights or remedies under or by reason of this
Agreement.

        14.    Entire Agreement; Amendments. This Agreement, together with the
Merger Agreement and the other documents referred to therein, contains the
entire agreement between the parties hereto with respect to the subject matter
hereof and supersedes all prior and contemporaneous agreements and
understandings, oral or written, with respect to such transactions. This
Agreement may not be changed, amended or modified orally, but may be changed
only by an agreement in writing signed by the party against whom any waiver,
change, amendment, modification or discharge may be sought.

        15.    Assignment. No party to this Agreement may assign any of its 
rights or obligations under this Agreement without the prior written consent of
the other party hereto, except that the Grantee may assign its rights and
obligations hereunder to any of its direct or 



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indirect wholly owned subsidiaries, but no such transfer shall relieve the
Grantee of its obligations hereunder if such transferee does not perform such
obligations. Any assignment made in violation of this Section 15 shall be void.

        16.    Headings. The section headings herein are for convenience only 
and shall not affect the construction of this Agreement.

        17.    Counterparts. This Agreement may be executed in any number of
counterparts, each of which, when executed, shall be deemed to be an original
and all of which together shall constitute one and the same document.

        18.    Governing Law. This Agreement shall be governed by and construed 
in accordance with the laws of the State of Delaware (regardless of the laws
that might otherwise govern under applicable Delaware principles of conflicts of
law).

        19.    Termination. The right to exercise the Option granted pursuant to
this Agreement shall terminate at the earlier of (i) the Effective Time (as
defined in the Merger Agreement), (ii) the date on which the Grantee realizes a
Total Profit of $65 million, (iii) the date on which the Merger Agreement is
terminated; provided the Option is not exercisable at such time and does not
become exercisable simultaneous with such termination and (iv) 90 days after the
date the Option becomes exercisable (the date referred to in clause (iv) being
hereinafter referred to as the "Option Termination Date"); provided that, if the
Option cannot be exercised or the Shares cannot be delivered to the Grantee upon
such exercise because the conditions set forth in Section 2(a) or Section 2(b)
hereof have not yet been satisfied, the Option Termination Date shall be
extended until thirty days after such impediment to exercise has been removed.

        All representations and warranties contained in this Agreement shall
survive delivery of and payment for the Shares.

        20.    Severability. If any term, provision, covenant or restriction of
this Agreement is held by a court of competent jurisdiction to be invalid, void
or unenforceable, the remainder of the terms, provisions, covenants and
restrictions of this Agreement shall remain in full force and effect and shall
in no way be affected, impaired or invalidated.

        21.    Public Announcement. The Grantee will consult with the Grantor 
and the Grantor will consult with the Grantee before issuing any press release
with respect to the initial announcement of this Agreement, the Option or the
transactions contemplated hereby and neither party shall issue any such press
release prior to such consultation except as may be required by law.

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             Signature page for Stock Option Agreement (Doubletree)



                  IN WITNESS WHEREOF, the Grantee and the Grantor have caused
this Agreement to be signed by their respective duly authorized officers as of
the date first written above.

                                DOUBLETREE CORPORATION



                                      /s/ Richard M. Kelleher
                                -------------------------------------------
                                By:   Richard M. Kelleher
                                Its:  President and Chief Executive Officer


                                PROMUS HOTEL CORPORATION


                                      /s/ Raymond E. Schultz
                                -------------------------------------------
                                By:   Raymond E. Schultz
                                Its:  President and Chief Executive Officer




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