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                                                                     EXHIBIT 4.7

                           PATTERSON-UTI ENERGY, INC.

                              AMENDED AND RESTATED

                          1997 LONG-TERM INCENTIVE PLAN

ARTICLE I: GENERAL

         SECTION 1.1 Purpose of the Plan. This Amended and Restated 1997
Long-Term Incentive Plan (the "Plan") of Patterson-UTI Energy, Inc. (the
"Company") is intended to advance the best interests of the Company, its
subsidiaries and its stockholders in order to attract, retain and motivate key
employees by providing them with additional incentives through (i) the grant of
options ("Options") to purchase shares of Common Stock, par value $.01 per
share, of the Company ("Common Stock"), (ii) the grant of stock appreciation
rights ("Stock Appreciation Rights"), (iii) the award of shares of restricted
Common Stock ("Restricted Stock") and (iv) the award of units payable in cash or
shares of Common Stock based on performance ("Performance Awards"), thereby
increasing the personal stake of such key employees in the continued success and
growth of the Company.

         SECTION 1.2 Administration of the Plan. (a) The Plan shall be
administered either by the full Board of Directors of the Company (the "Board of
Directors") or by the Compensation Committee or other designated committee of
the Board of Directors. The Board of Directors or such committee is referred to
herein as the "Committee". The Committee shall have authority to interpret
conclusively the provisions of the Plan, to adopt such rules and regulations for
carrying out the Plan as it may deem advisable, to decide conclusively all
questions of fact arising in the application of the Plan, to establish
performance criteria in respect of Awards (as defined herein) under the Plan, to
certify that Plan requirements have been met for any participant in the Plan, to
submit such matters as it may deem advisable to the Company's stockholders for
their approval, and to make all other determinations and take all other actions
necessary or desirable for the administration of the Plan. The Committee is
expressly authorized to adopt rules and regulations limiting or eliminating its
discretion in respect of certain matters as it may deem advisable to comply with
or obtain preferential treatment under any applicable tax or other law rule, or
regulation. All decisions and acts of the Committee shall be final and binding
upon all affected Plan participants.

         (b) The Committee shall designate the eligible employees, if any, to be
granted Awards and the type and amount of such Awards and the time when Awards
will be granted. All Awards granted under the Plan shall be on the terms and
subject to the conditions determined by the Committee consistent with the Plan.

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         SECTION 1.3 Eligible Participants. Key employees, including officers
and directors, of the Company and its subsidiaries (all such subsidiaries being
referred to as "Subsidiaries") shall be eligible for Awards under the Plan.

         SECTION 1.4 Awards Under the Plan. Awards to key employees may be in
the form of (i) Options, (ii) Stock Appreciation Rights, which may be issued
independent of or in tandem with Options, (iii) shares of Restricted Stock, (iv)
Performance Awards, or (v) any combination of the foregoing (collectively,
"Awards").

         SECTION 1.5 Shares Subject to the Plan. Initially, the aggregate number
of shares of Common Stock that may be issued under the Plan shall be 8,250,000,
subject to adjustment as provided in Section 5.2 of the Plan. Shares distributed
pursuant to the Plan may consist of authorized but unissued shares or treasury
shares of the Company, as shall be determined from time to time by the Board of
Directors.

         If any Award under the Plan shall expire, terminate or be canceled
(including cancellation upon an Option holder's exercise of a related Stock
Appreciation Right) for any reason without having been exercised in full, or if
any Award shall be forfeited to the Company, the unexercised or forfeited Award
shall not count against the above limits and shall again become available for
Awards under the Plan (unless the holder of such Award received dividends or
other economic benefits with respect to such Award, which dividends or other
economic benefits are not forfeited, in which case the Award shall count against
the above limits). Shares of Common Stock equal in number to the shares
surrendered in payment of the option price, and shares of Common Stock which are
withheld in order to satisfy Federal, state or local tax liability, shall count
against the above limits. Only the number of shares of Common Stock actually
issued upon exercise of a Stock Appreciation Right shall count against the above
limits, and any shares which were estimated to be used for such purposes and
were not in fact so used shall again become available for Awards under the Plan.
Cash exercises of Stock Appreciation Rights and cash settlement of other Awards
will not count against the above limits.

         The aggregate number of shares of Common Stock subject to Options or
Stock Appreciation Rights that may be granted to any one participant in any one
year under the Plan shall be 600,000, subject to adjustment as provided in
Section 5.2 of the Plan. The aggregate number of shares of Common Stock that may
be granted to any one participant in any one year in respect of Restricted Stock
shall be 600,000, subject to adjustment as provided in Section 5.2 of the Plan.
The aggregate number of shares of Common Stock that may be received by any one
participant in any one year in respect of a Performance Award shall be 600,000,
subject to adjustment as provided in Section 5.2 of the Plan, and the aggregate
amount of cash that may be received by any one participant in any one year in
respect to a Performance Award shall be $500,000.

         The total number of Awards (or portions thereof) settled in cash under
the Plan, based on the number of shares covered by such Awards (e.g., 100 shares
for a Stock Appreciation Right with respect to 100 shares), shall not exceed a
number equal to (i) the number of shares initially available for issuance under
the Plan plus (ii) the number of shares that have become available for issuance
under the Plan pursuant to the first paragraph of this Section 1.5.

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         The aggregate number of shares of Common Stock that are available under
the Plan for Options granted in accordance with Section 2.4(i) ("ISOs") is
600,000, subject to adjustment as provided in Section 5.2 of the Plan.

         SECTION 1.6 Other Compensation Programs. Nothing contained in the Plan
shall be construed to preempt or limit the authority of the Board of Directors
to exercise its corporate rights and powers, including, but not by way of
limitation, the right of the Board of Directors (i) to grant incentive awards
for proper corporate purposes otherwise than under the Plan to any employee,
officer, director or other person or entity or (ii) to grant incentive awards
to, or assume incentive awards of, any person or entity in connection with the
acquisition (whether by purchase, lease, merger, consolidation or otherwise) of
the business or assets (in whole or in part) of any person or entity.

ARTICLE II: STOCK OPTIONS AND STOCK APPRECIATION RIGHTS

         SECTION 2.1 Terms and Conditions of Options. Subject to the following
provisions, all Options granted under the Plan to employees of the Company and
its Subsidiaries shall be in such form and shall have such terms and conditions
as the Committee, in its discretion, may from time to time determine consistent
with the Plan.

         (a) Option Price. The option price per share shall be determined by the
Committee, except that in the case of an Option granted in accordance with
Section 2.4(i) the option price per share shall not be less than the fair market
value of a share of Common Stock (as determined by the Committee) on the date
the Option is granted (other than in the case of substitute or assumed Options
to the extent required to qualify such Options for preferential tax treatment
under the Code as in effect at the time of such grant).

         (b) Term of Option. The term of an Option shall be determined by the
Committee, except that the term of an Option shall not exceed ten years from the
date of grant, and, notwithstanding any other provision of this Plan, no Option
shall be exercised after the expiration of its term.

         (c) Exercise of Options. Options shall be exercisable at such time or
times and subject to such terms and conditions as the Committee shall specify in
the Option grant. Unless the Option grant specifies otherwise, the Committee
shall have discretion at any time to accelerate such time or times and otherwise
waive or amend any conditions in respect of all or any portion of the Options
held by any optionee. An Option may be exercised in accordance with its terms as
to any or all shares purchasable thereunder.

         (d) Payment for Shares. The Committee may authorize payment for shares
as to which an Option is exercised to be made in cash, shares of Common Stock, a
combination thereof, by "cashless exercise" or in such other manner as the
Committee in its discretion may provide.

         (e) Stockholder Rights. The holder of an Option shall, as such, have
none of the rights of a stockholder.

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         (f) Termination of Employment. The Committee shall have discretion to
specify in the Option grant, or, with the consent of the optionee, an amendment
thereof, provisions with respect to the period, not extending beyond the term of
the Option, during which the Option may be exercised following the optionee's
termination of employment.

         SECTION 2.2 Stock Appreciation Rights in Tandem with Options. (a) The
Committee may, either at the time of grant of an Option or at any time during
the term of the Option, grant Stock Appreciation Rights ("Tandem SARs") with
respect to all or any portion of the shares of Common Stock covered by such
Option. A Tandem SAR may be exercised at any time the Option to which it relates
is then exercisable, but only to the extent the Option to which it relates is
exercisable, and shall be subject to the conditions applicable to such Option.
When a Tandem SAR is exercised, the Option to which it relates shall cease to be
exercisable to the extent of the number of shares with respect to which the
Tandem SAR is exercised. Similarly, when an Option is exercised, the Tandem SARs
relating to the shares covered by such Option exercise shall terminate. Any
Tandem SAR which is outstanding on the last day of the term of the related
Option (as determined pursuant to Section 2.1(b)) shall be automatically
exercised on such date for cash without any action by the optionee.

         (b) Upon exercise of a Tandem SAR, the holder shall receive, for each
share with respect to which the Tandem SAR is exercised, an amount (the
"Appreciation") equal to the difference between the option price per share of
the Option to which the Tandem SAR relates and the fair market value (as
determined by the Committee) of a share of Common Stock on the date of exercise
of the Tandem SAR. The Appreciation shall be payable in cash, Common Stock, or a
combination of both, at the option of the Committee, and shall be paid within 30
days of the exercise of the Tandem SAR.

         SECTION 2.3 Stock Appreciation Rights Independent of Options. Subject
to the following provisions, all Stock Appreciation Rights granted independent
of Options ("Independent SARs") under the Plan to employees of the Company and
its Subsidiaries shall be in such form and shall have such terms and conditions
as the Committee, in its discretion, may from time to time determine consistent
with the Plan.

         (a) Exercise Price. The exercise price per share shall be determined by
the Committee on the date the Independent SAR is granted.

         (b) Term of Independent SAR. The term of an Independent SAR shall be
determined by the Committee, and, notwithstanding any other provision of this
Plan, no Independent SAR shall be exercised after the expiration of its term.

         (c) Exercise of Independent SARs. Independent SARs shall be exercisable
at such time or times and subject to such terms and conditions as the Committee
shall specify in the Independent SAR grant. Unless the Independent SAR grant
specifies otherwise, the Committee shall have discretion at any time to
accelerate such time or times and otherwise waive or amend any conditions in
respect of all or any portion of the Independent SARs held by any participant.
Upon exercise of an Independent SAR, the holder shall receive, for each share
specified in the Independent SAR grant, an amount (the "Appreciation") equal to
the difference between the

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exercise price per share specified in the Independent SAR grant and the fair
market value (as determined by the Committee) of a share of Common Stock on the
date of exercise of the Independent SAR. The Appreciation shall be payable in
cash, Common Stock, or a combination of both, at the option of the Committee,
and shall be paid within 30 days of the exercise of the Independent SAR.

         (d) Stockholder Rights. The holder of an Independent SAR shall, as
such, have none of the rights of a stockholder.

         (e) Termination of Employment. The Committee shall have discretion to
specify in the Independent SAR grant, or, with the consent of the holder, an
amendment thereof, provisions with respect to the period, not extending beyond
the term of the Independent SAR, during which the Independent SAR may be
exercised following the holder's termination of employment.

         SECTION 2.4 Statutory Options. Subject to the limitations on Option
terms set forth in Section 2.1, the Committee shall have the authority to grant
(i) ISOs within the meaning of Section 422 of the Internal Revenue Code of 1986,
as amended (the "Code"), and (ii) Options containing such terms and conditions
as shall be required to qualify such Options for preferential tax treatment
under the Code as in effect at the time of such grant, including, if then
applicable, limits with respect to minimum exercise price, duration and amounts
and special limitations applicable to any individual who, at the time the Option
is granted, owns stock possessing more than 10% of the total combined voting
power of all classes of stock of the Company or any affiliate. Options granted
pursuant to this Section 2.4 may contain such other terms and conditions
permitted by Article II of this Plan as the Committee, in its discretion, may
from time to time determine (including, without limitation, provision for Stock
Appreciation Rights), to the extent that such terms and conditions do not cause
the Options to lose their preferential tax treatment. If an Option intended to
be an ISO ceases or is otherwise not eligible to be an ISO, such Option (or
portion thereof necessary to maintain the status of the remaining portion of the
Option as an ISO) shall remain valid but be treated as an Option other than an
ISO.

         SECTION 2.5 Change of Control. Notwithstanding the exercisability
schedule governing any Option or Stock Appreciation Right, upon the occurrence
of a Change of Control (as defined in Section 5.8) all Options and Stock
Appreciation Rights outstanding at the time of such Change of Control and held
by participants who are employees of the Company or its subsidiaries at the time
of such Change of Control shall (unless specifically provided otherwise in the
grant thereof) become immediately exercisable and, unless the participant agrees
otherwise in writing, remain exercisable for three years (but not beyond the
term of the Option or Stock Appreciation Right) after the employee's termination
of employment for any reason other than termination by the Company or a
subsidiary of the Company for dishonesty, conviction of a felony, willful
unauthorized disclosure of confidential information or willful refusal to
perform the duties of such employee's position or positions with the Company or
such subsidiary (termination for "cause"); provided that this Section 2.5 shall
not apply to Awards granted to a participant if, in connection with a Change of
Control pursuant to clause (1) of Section 5.8, such participant is the Person or
forms part of the Person specified in such clause (1).

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ARTICLE III:  RESTRICTED STOCK

    SECTION 3.1 Terms and Conditions of Restricted Stock Awards. Subject to the
following provisions, all Awards of Restricted Stock under the Plan to employees
of the Company and its Subsidiaries shall be in such form and shall have such
terms and conditions as the Committee, in its discretion, may from time to time
determine consistent with the Plan.

         (a) Restricted Stock Award. The Restricted Stock Award shall specify
the number of shares of Restricted Stock to be awarded, the price, if any, to be
paid by the recipient of the Restricted Stock, and the date or dates on which
the Restricted Stock will vest. The vesting and number of shares of Restricted
Stock may be conditioned upon the completion of a specified period of service
with the Company or its Subsidiaries, upon the attainment of specified
performance objectives, or upon such other criteria as the Committee may
determine in accordance with the provisions hereof. Performance objectives will
be based on increases in share prices, operating income, net income or cash flow
thresholds on a company wide, subsidiary or division or group basis, rig
utilization, safety records, return on common equity or any combination of the
foregoing.

         (b) Restrictions on Transfer. Stock certificates representing the
Restricted Stock granted to an employee shall be registered in the employee's
name. Such certificates shall either be held by the Company on behalf of the
employee, or delivered to the employee bearing a legend to restrict transfer of
the certificate until the Restricted Stock has vested, as determined by the
Committee. The Committee shall determine whether the employee shall have the
right to vote and/or receive dividends on the Restricted Stock before it has
vested. No share of Restricted Stock may be sold, transferred, assigned, or
pledged by the employee until such share has vested in accordance with the terms
of the Restricted Stock Award. Unless the grant of a Restricted Stock Award
specifies otherwise, in the event of an employee's termination of employment
before all the employee's Restricted Stock has vested, or in the event other
conditions to the vesting of Restricted Stock have not been satisfied prior to
any deadline for the satisfaction of such conditions set forth in the Award, the
shares of Restricted Stock that have not vested shall be forfeited and any
purchase price paid by the employee shall be returned to the employee. At the
time Restricted Stock vests (and, if the employee has been issued legended
certificates of Restricted Stock, upon the return of such certificates to the
Company), a certificate for such vested shares shall be delivered to the
employee or the employee's estate, free of all restrictions.

         (c) Accelerated Vesting. Notwithstanding the vesting conditions set
forth in the Restricted Stock Award, (i) unless the Restricted Stock grant
specifies otherwise, the Committee may in its discretion at any time accelerate
the vesting of Restricted Stock or otherwise waive or amend any conditions of a
grant of Restricted Stock, and (ii) all shares of Restricted Stock shall vest
upon a Change of Control of the Company; provided that clause (ii) above shall
not apply to Awards granted to a participant if, in connection with a Change of
Control pursuant to clause (1) of Section 5.8, such participant is the Person or
forms part of the Person specified in such clause (1).

         (d) Maximum Number. The maximum aggregate number of shares of
Restricted Stock which may be awarded under the Plan shall be 500,000 shares.

ARTICLE IV:  PERFORMANCE AWARDS

         SECTION 4.1 Terms and Conditions of Performance Awards. The Committee
shall be authorized to grant Performance Awards, which are payable in stock,
cash or a combination thereof, at the discretion of the Committee.

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         (a) Performance Period. The Committee shall establish with respect to
each Performance Award a performance period over which the performance goal of
such Performance Award shall be measured. The performance period for a
Performance Award shall be established prior to the time such Performance Award
is granted and may overlap with performance periods relating to other
Performance Awards granted hereunder to the same employee.

         (b) Performance Objectives. The Committee shall establish a minimum
level of acceptable achievement for the holder at the time of each Award. Each
Performance Award shall be contingent upon future performances and achievement
of objectives described either in terms of Company-wide performance or in terms
that are related to performance of the employee or of the division, subsidiary,
department or function within the Company in which the employee is employed. The
Committee shall have the authority to establish the specific performance
objectives and measures applicable to such objectives. Such objectives, however,
shall be based on increases in share prices, operating income, net income or
cash flow thresholds on a company wide, subsidiary or division or group, rig
utilization, safety records, return on common equity or any combination of the
foregoing.

         (c) Size, Frequency and Vesting. The Committee shall have the authority
to determine at the time of the Award the maximum value of a Performance Award,
the frequency of Awards and the date or dates when Awards vest.

         (d) Payment. Following the end of each performance period, the holder
of each Performance Award will be entitled to receive payment of an amount, not
exceeding the maximum value of the Performance Award, based on the achievement
of the performance measures for such performance period, as determined by the
Committee. If at the end of the performance period the specified objectives have
been attained, the employee shall be deemed to have fully earned the Performance
Award. If the employee exceeds the specified minimum level of acceptable
achievement but does not fully attain such objectives, the employee shall be
deemed to have partly earned the Performance Award, and shall become entitled to
receive a portion of the total Award, as determined by the Committee. If a
Performance Award is granted after the start of a performance period, the Award
shall be reduced to reflect the portion of the performance period during which
the Award was in effect. Unless the Award specifies otherwise, including
restrictions in order to satisfy the conditions under Section 162(m) of the
Code, the Committee may adjust the payment of Awards or the performance
objectives if events occur or circumstances arise which would cause a particular
payment or set of performance objectives to be inappropriate, as determined by
the Committee.

         (e) Termination of Employment. A recipient of a Performance Award who,
by reason of death, disability or retirement, terminates employment before the
end of the applicable performance period shall be entitled to receive, to the
extent earned, a portion of the Award which is proportional to the portion of
the performance period during which the employee was employed. A recipient of a
Performance Award who terminates employment for any other reason shall not be
entitled to any part of the Award unless the Committee determines otherwise;

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however, the Committee may in no event pay the employee more than that portion
of the Award which is proportional to his or her period of actual service.

         (f) Accelerated Vesting. Notwithstanding the vesting conditions set
forth in a Performance Award, (i) unless the Award specifies otherwise, the
Committee may in its discretion at any time accelerate vesting of the Award or
otherwise waive or amend any conditions (including but not limited to
performance objectives) in respect of a Performance Award, and (ii) all
Performance Awards shall vest upon a Change of Control of the Company. In
addition, each participant in the Plan shall receive the maximum Performance
Award he or she could have earned for the proportionate part of the performance
period prior to the Change of Control, and shall retain the right to earn any
additional portion of his or her Award if he or she remains in the Company's
employ. However, clause (ii) above shall not apply to Awards granted to a
participant if, in connection with a Change of Control pursuant to clause (1) of
Section 5.8, such participant is the Person or forms part of the Person
specified in such clause (1).

         (g) Stockholder Rights. The holder of a Performance Award shall, as
such, have none of the rights of a stockholder.

ARTICLE V:  ADDITIONAL PROVISIONS

         SECTION 5.1 General Restrictions. Each Award under the Plan shall be
subject to the requirement that, if at any time the Committee shall determine
that (i) the listing, registration or qualification of the shares of Common
Stock subject or related thereto upon any securities exchange or under any state
or Federal law, or (ii) the consent or approval of any government regulatory
body, or (iii) an agreement by the recipient of an Award with respect to the
disposition of shares of Common Stock, is necessary or desirable (in connection
with any requirement or interpretation of any Federal or state securities law,
rule or regulation) as a condition of, or in connection with, the granting of
such Award or the issuance, purchase or delivery of shares of Common Stock
thereunder, such Award may not be consummated in whole or in part unless such
listing, registration, qualification, consent, approval or agreement shall have
been effected or obtained free of any conditions not acceptable to the
Committee.

         SECTION 5.2 Adjustments for Changes in Capitalization. In the event of
any stock dividends, stock splits, recapitalizations, combinations, exchanges of
shares, mergers, consolidation, liquidations, split-ups, split-offs, spin- offs,
or other similar changes in capitalization, or any distribution to stockholders,
including a rights offering, other than regular cash dividends, changes in the
outstanding stock of the Company by reason of any increase or decrease in the
number of issued shares of Common Stock resulting from a split-up or
consolidation of shares or any similar capital adjustment or the payment of any
stock dividend, any share repurchase at a price in excess of the market price of
the Common Stock at the time such repurchase is announced or other increase or
decrease in the number of such shares, the Committee shall make appropriate
adjustment in the number and kind of shares authorized by the Plan (including
shares available for ISOs), in the number, price or kind of shares covered by
the Awards and in any outstanding Awards under the Plan; provided, however, that
no such adjustment shall increase the aggregate value of any outstanding Award.

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         In the event of any adjustment in the number of shares covered by any
Award, any fractional shares resulting from such adjustment shall be disregarded
and each such Award shall cover only the number of full shares resulting from
such adjustment.

         SECTION 5.3 Amendments. (a) The Board of Directors may at any time and
from time to time and in any respect amend or modify the Plan.

         (b) The Committee shall have the authority to amend any Award to
include any provision which, at the time of such amendment, is authorized under
the terms of the Plan; however, no outstanding Award may be revoked or altered
in a manner unfavorable to the holder without the written consent of the holder.

         SECTION 5.4 Withholding. Whenever the Company proposes or is required
to issue or transfer shares of Common Stock under the Plan, the Company shall
have the right to require the holder to pay an amount in cash or to retain or
sell without notice, or demand surrender of, shares of Common Stock in value
sufficient to satisfy any Federal, state or local withholding tax liability
("Withholding Tax") prior to the delivery of any certificate for such shares (or
remainder of shares if Common Stock is retained to satisfy such tax liability).
Whenever under the Plan payments are to be made in cash, such payments shall be
net of an amount sufficient to satisfy any Federal, state or local withholding
tax liability. An Award may also provide the holder with the right to satisfy
the Withholding Tax with previously owned shares of Common Stock or shares of
Common Stock otherwise issuable to the holder.

         Whenever Common Stock is so retained or surrendered to satisfy
Withholding Tax, the value of shares of Common Stock so retained or surrendered
shall be determined by the Committee, and the value of shares of Common Stock so
sold shall be the net proceeds (after deduction of commissions) received by the
Company from such sale, as determined by the Committee.

         SECTION 5.5 Non-assignability. Except as expressly provided in the Plan
or in any agreements, no Award under the Plan shall be assignable or
transferable by the holder thereof except by will or by the laws of descent and
distribution. During the life of the holder, Awards under the Plan shall be
exercisable only by such holder or by the guardian or legal representative of
such holder.

         SECTION 5.6 Non-uniform Determinations. Determinations by the Committee
under the Plan (including, without limitation, determinations of the persons to
receive Awards; the form, amount and timing of such Awards; the terms and
provisions of such Awards and the agreements evidencing same; and provisions
with respect to termination of employment) need not be uniform and may be made
by it selectively among persons who receive, or are eligible to receive, Awards
under the Plan, whether or not such persons are similarly situated.

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         SECTION 5.7 No Guarantee of Employment. The grant of an Award under the
Plan shall not constitute an assurance of continued employment for any period or
any obligation of the Board of Directors to nominate any director for reelection
by the Company's stockholders.

         SECTION 5.8 Change of Control. A "Change of Control" shall be deemed to
have occurred if:

         (1) any Person (as defined below), other than a Designated Person, is
or becomes the Beneficial Owner (as defined below) of securities of the Company
representing 35% or more of the Voting Power (as defined below);

         (2) there shall occur a change in the composition of a majority of the
Board of Directors within any period of four consecutive years which change
shall not have been approved by a majority of the Board of Directors as
constituted immediately prior to the commencement of such period;

         (3) at any meeting of the stockholders of the Company called for the
purpose of electing directors, more than one of the persons nominated by the
Board of Directors for election as directors shall fail to be elected; or

         (4) a merger, consolidation, sale of substantially all assets or other
reorganization of the Company, other than a reincorporation, in which the
Company does not survive, shall occur.

         For purposes of this Section 5.8, (i) "Person" shall have the meaning
set forth in Sections 3(a)(9) and 13(d)(3) of the Securities Exchange Act of
1934 (the "Exchange Act"), as in effect on May 1, 1997, (ii) "Beneficial Owner"
shall have the meaning set forth in Rules 13d-3 and 13d-5 promulgated under the
Exchange Act on May 1, 1997; (iii) "Voting Power" shall mean the voting power of
the outstanding securities of the Company having the right under ordinary
circumstances to vote at an election of the Board of Directors; and (iv)
"Designated Person" shall mean any Person whose Beneficial Ownership of
securities is solely the result of such Person acquiring securities as an
underwriter in an underwritten public offering of such securities.
Notwithstanding anything contained herein to the contrary, a Change in Control
shall not be deemed to have occurred due to the Voting Power of Remy Capital
Partners III, L.P. or any of its affiliates (collectively "Remy") falling below
35% or subsequently increasing over 35%.

         SECTION 5.9 Duration and Termination. (a) The Plan shall be of
unlimited duration. Notwithstanding the foregoing, no ISO (within the meaning of
Section 422 of the Code) shall be granted under the Plan ten (10) years after
the effective date of the Plan, but Awards granted prior to such date may extend
beyond such date, and the terms of this Plan shall continue to apply to all
Awards granted hereunder.

          (b) The Board of Directors may suspend, discontinue or terminate the
Plan at any time. Such action shall not impair any of the rights of any holder
of any Award outstanding on the date of the Plan's suspension, discontinuance or
termination without the holder's written consent.

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         SECTION 5.10 Deferred Compensation and Trust Agreements. The Committee
may authorize and establish deferred compensation agreements and arrangements in
connection with Awards under the Plan and may establish trusts and other
arrangements including "rabbi trusts", with respect to such agreements and
appoint one or more trustees for such trusts. Shares of Common Stock under the
Plan may also be acquired by one or more trustees from the Company, in the open
market or otherwise.

         SECTION 5.11 Effective Date. The Plan is effective as of July 23, 1997,
the effective date of the Long-Term Incentive Plan prior to amendment.

                                       11<PAGE>
                                                                     EXHIBIT 4.8

                              AMENDED AND RESTATED
                           PATTERSON-UTI ENERGY, INC.
                     NON-EMPLOYEE DIRECTOR STOCK OPTION PLAN

    1. Purpose. This Amended and Restated Non-Employee Director Stock Option
Plan (the "Plan") of Patterson-UTI Energy, Inc. (the "Company") was adopted for
the benefit of the directors of the Company who at the time of their service are
not employees of the Company or any of its subsidiaries ("Non-Employee
Directors"), and is intended to advance the interests of the Company by
providing the Non- Employee Directors with additional incentive to serve the
Company by increasing their proprietary interest in the success of the Company.

    2. Administration. The Plan shall be administered by a committee of the
Board of Directors of the Company (the "Committee"), the members of which shall
consist solely of directors who are employees of the Company. For the purposes
of the Plan, a majority of the members of the Committee shall constitute a
quorum for the transaction of business, and the vote of a majority of those
members present at any meeting shall decide any question brought before that
meeting. In addition, the Committee may take any action otherwise proper under
the Plan by the affirmative vote, taken without a meeting, of a majority of its
members. No member of the Committee shall be liable for any act or omission of
any other member of the Committee or for any act or omission on his own part,
including but not limited to the exercise of any power or discretion given to
him under the Plan, except those resulting from his own gross negligence or
willful misconduct. Except as otherwise expressly provided for herein, all
questions of interpretation and application of the Plan, or as to options
granted hereunder (the "Options"), shall be subject to the determination, which
shall be final and binding, of a majority of the whole Committee.
Notwithstanding the above, the selection of Non-Employee Directors to whom
Options are to be granted, the number of shares subject to any Option, the
exercise price of any Option and the term of any Option shall be as hereinafter
provided and the Committee shall have no discretion as to such matters.

    3. Option Shares. The stock subject to the Options and other provisions of
the Plan shall be shares of the Company's Common Stock, $.01 par value (or such
other par value as may be designated by act of the Company's stockholders) (the
"Common Stock"). The total amount of the Common Stock with respect to which
Options may be granted shall not exceed in the aggregate 600,000 shares;
provided, that the class and aggregate number of shares which may be subject to
the Options granted hereunder shall be subject to adjustment in accordance with
the provisions of Paragraph 12 hereof. Such shares may be treasury shares or
authorized but unissued shares.

    In the event that any outstanding Option for any reason shall expire or
terminate by reason of the death of the optionee or the fact that the optionee
ceases to be a director, the surrender of any

<PAGE>

such Option, or any other cause, the shares of Common Stock allocable to the
unexercised portion of such Option may again be subject to an Option under the
Plan.

    4. Grant of Options. Subject to the provisions of Paragraph 16 and the
availability under the Plan of a sufficient number of shares of Common Stock
that may be issuable upon the exercise of outstanding Options, there shall be
granted the following Options:

    (a) To each Non-Employee Director as of the date he is first elected as a
director of the Company, an Option to purchase 20,000 shares, subject to
adjustment as provided in Paragraph 12 hereof, of Common Stock at a purchase
price per share of Common Stock (the "Option Price") equal to the fair market
value of the Common Stock as defined in Paragraph 7 hereof as of the date of
grant; and

    (b) Each Non-Employee Director who has served as a non-employee director for
a period of at least one year shall receive on each December 31 on which such
person is a Non-Employee Director, an Option to purchase 10,000 shares, subject
to adjustment as provided in Paragraph 12 hereof, of Common Stock at an Option
Price equal to the fair market value of the Common Stock as defined in Paragraph
7 hereof as of the date of grant.

No Option shall be granted pursuant to the Plan after December 18, 2005.

    5. Duration of Options. Each Option granted under the Plan shall be
exercisable for a term of five years from the date of grant, subject to earlier
termination as provided in Paragraph 9 hereof.

    6. Amount Exercisable. Each Option granted pursuant to the Plan shall not be
exercisable for a period of one year from the date of grant. After such time,
such Option shall be fully vested and exercisable throughout the term of the
Option. Notwithstanding the foregoing, no Option granted by virtue of the
amendments effected by this Plan shall be exercisable for a period of six months
following stockholder approval.

    7. Exercise of Options. An optionee may exercise such optionee's Option by
delivering to the Company a written notice stating (i) that such optionee wishes
to exercise such Option on the date such notice is so delivered, (ii) the number
of shares of stock with respect to which such Option is to be exercised, (iii)
the address to which the certificate representing such shares of stock should be
mailed, and (iv) the social security number of such optionee. In order to be
effective, such written notice shall be accompanied by (i) payment of the Option
Price of such shares of stock and (ii) if applicable, payment of an amount of
money necessary to satisfy any withholding tax liability that may result from
the exercise of such Option. Each such payment shall be made by check drawn on a
national banking association and payable to the order of the Company in United
States dollars.

    If, at the time of receipt by the Company of such written notice, (i) the
Company has unrestricted surplus in an amount not less than the Option Price of
such shares of stock, (ii) all accrued cumulative preferential dividends and
other current preferential dividends on all outstanding shares of preferred
stock of the Company have been fully paid, (iii) the acquisition by the Company
of its own shares of stock for the purpose of enabling such optionee to exercise

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                                                                          Page 2

<PAGE>

such Option is otherwise permitted by applicable law and without any vote or
consent of any stockholder of the Company, and (iv) there shall have been
adopted, and there shall be in full force and effect, a resolution of the Board
of Directors of the Company authorizing the acquisition by the Company of its
own shares of stock for such purpose, then such optionee may deliver to the
Company, in payment of the Option Price of the shares of stock with respect to
which such Option is exercised, (x) certificates registered in the name of such
optionee that represent a number of shares of stock legally and beneficially
owned by such optionee (free of all liens, claims and encumbrances of every
kind) and having a fair market value on the date of receipt by the Company of
such written notice that is not greater than the Option Price of the shares of
stock with respect to which such Option is to be exercised, such certificates to
be accompanied by stock powers duly endorsed in blank by the record holder of
the shares of stock represented by such certificates, with the signature of such
record holder guaranteed by a national banking association (or, in lieu of such
certificates, other arrangements for the transfer of such shares to the Company
which are satisfactory to the Company) and (y) if the Option Price of the shares
of stock with respect to which such Options are to be exercised exceeds such
fair market value, a check drawn on a national banking association and payable
to the order of the Company in an amount, in United States dollars, equal to the
amount of such excess plus the amount of money necessary to satisfy any
withholding tax liability that may result from the exercise of such Option.
Notwithstanding the provisions of the immediately preceding sentence, the
Committee, in its sole discretion, may refuse to accept shares of stock in
payment of the Option Price of the shares of stock with respect to which such
Option is to be exercised and, in that event, any certificates representing
shares of stock that were received by the Company with such written notice shall
be returned to such optionee, together with notice by the Company to such
optionee of the refusal of the Committee to accept such shares of stock. The
Company may, at its option and upon approval by the Board of Directors of the
Company, retain shares of Common Stock which would otherwise be issued upon
exercise of an Option to satisfy any withholding tax liability that may result
from the exercise of such Option, which shares shall be valued for such purpose
at their then fair market value. If, at the expiration of seven business days
after the delivery to such optionee of such written notice from the Company,
such optionee shall not have delivered to the Company a check drawn on a
national banking association and payable to the order of the Company in an
amount, in United States dollars, equal to the Option Price of the shares of
stock with respect to which such Option is to be exercised, such written notice
from the optionee to the Company shall be ineffective to exercise such Option.

    As promptly as practicable after the receipt by the Company of (i) such
written notice from the optionee, (ii) payment, in the form required by the
foregoing provisions of this Paragraph 7, of the Option Price of the shares of
stock with respect to which such Option is to be exercised, and (iii) payment,
if required, in the form required by the foregoing provisions of this Paragraph
7, of an amount necessary to satisfy any withholding tax liability that may
result from the exercise of such Option, a certificate representing the number
of shares of stock with respect to which such Option has been so exercised,
reduced, to the extent applicable by the number of shares retained by the
Company to pay any required withholding tax, such certificate to be registered
in the name of such optionee, provided that such delivery shall be considered to
have been made when such certificate shall have been mailed, postage prepaid, to
such optionee at the address specified for such purpose in such written notice
from the optionee to the Company.

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                                                                          Page 3
<PAGE>

    For purposes of this Paragraph 7, the "fair market value" of a share of
stock as of any particular date shall mean the closing sale price of a share of
Common Stock on that date as reported by the principal national securities
exchange on which the Common Stock is listed if the Common Stock is then listed
on a national securities exchange, or if the Common Stock is not so listed, the
average of the bid and asked price of a share of Common Stock on that date and
reported in the National Association of Securities Dealers Automated Quotation
system (the "NASDAQ System"); provided that if no such closing price or quotes
are so reported on that date or if in the discretion of the Committee another
means of determining the fair market value of a share of stock at such date
shall be necessary or advisable, the Committee may provide for another means for
determining such fair market value.

    8.  Transferability of Options. Options shall not be transferable by the
optionee otherwise than by will or under the laws of descent and distribution,
and shall be exercisable, during his lifetime, only by him.

    9.  Termination. Except as may be otherwise expressly provided herein,
each Option, to the extent it shall not previously have been exercised, shall
terminate on the earlier of the following:

    (a) On the last day within the three month period commencing on the date on
        which the optionee ceases to be a member of the Company's Board of
        Directors, for any reason other than the death, disability or retirement
        of the optionee, during which period the optionee shall be entitled to
        exercise all Options fully vested as described in Paragraph 6 by the
        optionee on which the optionee ceased on the date on which the optionee
        ceased be a member of the Company's Board of Directors;

    (b) On the last day within the one year period commencing on the date on
        which the optionee ceases to be a member of the Company's Board of
        Directors because of permanent disability, during which period the
        optionee shall be entitled to exercise all Options fully vested as
        described in Paragraph 6 by the optionee on the date on which the
        optionee ceased to be a member of the Company's Board of Directors
        because of such disability;

    (c) On the last day within the one year period commencing on the date of the
        optionee's death while serving as a member of the Company's Board of
        Directors, during which period the executor or administrator of the
        optionee's estate or the person or persons to whom the optionee's Option
        shall have been transferred by will or the laws of descent or
        distribution, shall be entitled to exercise all Options in respect of
        the number of shares that the optionee would have been entitled to
        purchase had the optionee exercised such Options on the date of his
        death;

    (d) On the last day within the one year period commencing on the date an
        optionee who has had at least five years of service on the Board of
        Directors of the Company retires from the Board of Directors of the
        Company, during which period the optionee, or the executor or
        administrator of the optionee's estate or the person or persons to whom
        such Option shall have been transferred by the will or the laws of
        descent or distribution in the event of the optionee's death within such
        one year period, as the case may be, shall be entitled to exercise all
        Options in respect of the number of shares that the optionee would have
        been

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                                                                          Page 4
<PAGE>

        entitled to purchase had the optionee exercised such Options on the
        date of such retirement; and

    (e) Five years after the date of grant of such Option.

    10. Requirements of Law. The Company shall not be required to sell or issue
any shares under any Option if the issuance of such shares shall constitute a
violation by the optionee or the Company of any provisions of any law or
regulation of any governmental authority. Each Option granted under the Plan
shall be subject to the requirements that, if at any time the Board of Directors
of the Company or the Committee shall determine that the listing, registration
or qualification of the shares subject thereto upon any securities exchange or
under any state or federal law of the United States or of any other country or
governmental subdivision thereof, or the consent or approval of any governmental
regulatory body, or investment or other representations, are necessary or
desirable in connection with the issue or purchase of shares subject thereto, no
such Option may be exercised in whole or in part unless such listing,
registration, qualification, consent, approval or representation shall have been
effected or obtained free of any conditions not acceptable to the Board of
Directors. If required at any time by the Board of Directors or the Committee,
an Option may not be exercised until the optionee has delivered an investment
letter to the Company. In addition, specifically in connection with the
Securities Act of 1933 (as now in effect or hereafter amended), upon exercise of
any Option, the Company shall not be required to issue the underlying shares
unless the Committee has received evidence satisfactory to it to the effect that
the holder of such Option will not transfer such shares except pursuant to a
registration statement in effect under such Act or unless an opinion of counsel
satisfactory to the Company has been received by the Committee to the effect
that such registration is not required. Any determination in this connection by
the Committee shall be final, binding and conclusive. In the event the shares
issuable on exercise of an Option are not registered under the Securities Act of
1933, the Company may imprint on the certificate for such shares the following
legend or any other legend which counsel for the Company considers necessary or
advisable to comply with the Securities Act of 1933:

    "The shares of stock represented by this certificate have not been
    registered under the Securities Act of 1933 or under the securities laws of
    any state and may not be sold or transferred except upon such registration
    or upon receipt by the Corporation of an opinion of counsel satisfactory, in
    form and substance to the Corporation, that registration is not required for
    such sale or transfer."

The Company may, but shall in no event be obligated to, register any securities
covered hereby pursuant to the Securities Act of 1933 (as now in effect or as
hereafter amended) and, in the event any shares are so registered, the Company
may remove any legend on certificates representing such shares. The Company
shall not be obligated to take any other affirmative action in order to cause
the exercise of an Option or the issuance of shares pursuant thereto to comply
with any law or regulation of any governmental authority.

    11. No Rights as Stockholder. No optionee shall have rights as a stockholder
with respect to shares covered by his Option until the date of issuance of a
stock certificate for such shares; and,

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                                                                          Page 5
<PAGE>

except as otherwise provided in Paragraph 12 hereof, no adjustment for
dividends, or otherwise, shall be made if the record date therefor is prior to
the date of issuance of such certificate.

    12. Changes in the Company's Capital Structure. The existence of outstanding
Options shall not affect in any way the right or power of the Company or its
stockholders to make or authorize any or all adjustments, recapitalizations,
reorganizations or other changes in the Company's capital structure or its
business, or any merger or consolidation of the Company, or any issue of bonds,
debentures, preferred or prior preference stock ahead of or affecting the Common
Stock or the rights thereof, or the dissolution or liquidation of the Company,
or any sale or transfer of all or any part of its assets or business, or any
other corporate act or proceeding, whether of a similar character or otherwise.

    If the Company shall effect a subdivision or consolidation of shares or
other capital adjustment of, or the payment of a dividend in capital stock or
other equity securities of the Company on, its Common Stock, or other increase
or reduction of the number of shares of the Common Stock without receiving
consideration therefor in money, services, or property, or the reclassification
of its Common Stock, in whole or in part, into other equity securities of the
Company, then (a) the number, class and per share price of shares of stock
subject to outstanding Options hereunder shall be appropriately adjusted (or in
the case of the issuance of equity securities as a dividend on, or in a
reclassification of, the Common Stock, the Options shall extend to such other
securities) in such a manner as to entitle an optionee to receive, upon exercise
of an Option, for the same aggregate cash compensation, the same total number
and class or classes of shares (or in the case of a dividend of, or
reclassification into, other equity securities, such other securities) he would
have held after such adjustment if he had exercised his Option in full
immediately prior to the event requiring the adjustment, or, if applicable, the
record date for determining stockholders to be affected by such adjustment; and
(b) the number and class of shares then reserved for issuance under the Plan (or
in the case of a dividend of, or reclassification into, other equity securities,
such other securities) shall be adjusted by substituting for the total number
and class of shares of stock then received, the number and class or classes of
shares of stock (or in the case of a dividend of, or reclassification into,
other equity securities, such other securities) that would have been received by
the owner of an equal number of outstanding shares of Common Stock as the result
of the event requiring the adjustment. Comparable rights shall accrue to each
optionee in the event of successive subdivisions, consolidations, capital
adjustment, dividends or reclassifications of the character described above.

    If the Company shall distribute to all holders of its shares of Common Stock
(including any such distribution made to non-dissenting stockholders in
connection with a consolidation or merger in which the Company is the surviving
corporation and in which holders of shares of Common Stock continue to hold
shares of Common Stock after such merger or consolidation) evidences of
indebtedness or cash or other assets (other than cash dividends payable out of
consolidated retained earnings not in excess of, in any one year period, the
greater of (a) $.10 per share of Common Stock and (b) two times the aggregate
amount of dividends per share paid during the preceding calendar year and
dividends or distributions payable in shares of Common Stock or other equity
securities of the Company described in the immediately preceding paragraph),
then in each case the Option Price shall be adjusted by reducing the Option
Price in

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                                                                          Page 6
<PAGE>

effect immediately prior to the record date for the determination of
stockholders entitled to receive such distribution by the fair market value, as
determined in good faith by the Board of Directors of the Company (whose
determination shall be described in a statement filed in the Company's corporate
records and be available for inspection by any holder of an Option) of the
portion of the evidence of indebtedness or cash or other assets so to be
distributed applicable to one share of Common Stock; provided that in no event
shall the Option Price be less than the par value of a share of Common Stock.
Such adjustment shall be made whenever any such distribution is made, and shall
become effective on the date of the distribution retroactive to the record date
for the determination of the stockholders entitled to receive such distribution.
Comparable adjustments shall be made in the event of successive distributions of
the character described above.

    After the Company shall make a tender offer for, or grant to all of its
holders of its shares of Common Stock the right to require the Company to
acquire from such stockholders shares of, Common Stock, at a price in excess of
the Current Market Price (a "Put Right") or the Company shall grant to all of
its holders of its shares of Common Stock the right to acquire shares of Common
Stock for less than the Current Market Price (a "Purchase Right") then, in the
case of a Put Right, the Option Price shall be adjusted by multiplying the
Option Price in effect immediately prior to the record date for the
determination of stockholders entitled to receive such Put Right by a fraction,
the numerator of which shall be the number of shares of Common Stock then
outstanding minus the number of shares of Common Stock which could be purchased
at the Current Market Price for the aggregate amount which would be paid if all
Put Rights are exercised and the denominator of which is the number of shares of
Common Stock which would be outstanding if all Put Rights are exercised; and, in
the case of a Purchase Right, the Option Price shall be adjusted by multiplying
the Option Price in effect immediately prior to the record date for the
determination of the stockholders entitled to receive such Purchase Right by a
fraction, the numerator of which shall be the number of shares of Common Stock
then outstanding plus the number of shares of Common Stock which could be
purchased at the Current Market Price for the aggregate amount which would be
paid if all Purchase Rights are exercised and the denominator of which is the
number of shares of Common Stock which would be outstanding if all Purchase
Rights are exercised. In addition, the number of shares subject to the Option
shall be increased by multiplying the number of shares then subject to the
Option by a fraction which is the inverse of the fraction used to adjust the
Option Price. Notwithstanding the foregoing if any such Put Rights or Purchase
Rights shall terminate without being exercised, the Option Price and number of
shares subject to Option shall be appropriately readjusted to reflect the Option
Price and number of shares subject to the Option which would have been in effect
if such unexercised Rights had never existed. Comparable adjustments shall be
made in the event of successive transactions of the character described above.

    After the merger of one or more corporations into the Company, after any
consolidation of the Company and one or more corporations, or after any other
corporate transaction described in Section 424(a) of the Internal Revenue Code
of 1986, as amended (the "Code") in which the Company shall be the surviving
corporation, each optionee, at no additional cost, shall be entitled to receive,
upon any exercise of his Option, in lieu of the number of shares as to which the
Option shall then be so exercised, the number and class of shares of stock or
other equity securities to which the optionee would have been entitled pursuant
to the terms of the agreement

--------------------------------------------------------------------------------
                                                                          Page 7
<PAGE>

of merger or consolidation if at the time of such merger or consolidation such
optionee had been a holder of a number of shares of Common Stock equal to the
number of shares as to which the Option shall then be so exercised and, if as a
result of such merger, consolidation or other transaction, the holders of Common
Stock are not entitled to receive any shares of Common Stock pursuant to the
terms thereof, each optionee, at no additional cost, shall be entitled to
receive, upon exercise of his Option, such other assets and property, including
cash, to which he would have been entitled if at the time of such merger,
consolidation or other transaction he had been the holder of the number of
shares of Common Stock equal to the number of shares as to which the Option
shall then be so exercised. Comparable rights shall accrue to each optionee in
the event of successive mergers or consolidations of the character described
above.

    After a merger of the Company into one or more corporations, after any
consolidation of the Company and any one or more corporations, or after any
other corporate transaction described in Section 424(a) of the Code in which the
Company is not the surviving corporation, each optionee shall, at no additional
cost, be entitled at the option of the surviving corporation, (i) to have his
then existing Option assumed or to have a new option substituted for the
existing Option by the surviving corporation to the transaction which is then
employing him, or a parent or subsidiary of such corporation, on a basis where
the excess of the aggregate fair market value of the shares subject to the
option immediately after the substitution or assumption over the aggregate
option price of such option is equal to the excess of the aggregate fair market
value of all shares subject to the option immediately before such substitution
or assumption over the aggregate option price of such shares, provided that the
shares subject to the new option must be traded on the New York Stock Exchange
or the American Stock Exchange or quoted on the NASDAQ, or (ii) to receive upon
any exercise of his Option, in lieu of the number of shares as to which the
Option shall then be so exercised, the securities, property and other assets,
including cash, to which the Optionee would have been entitled pursuant to the
terms of the agreement of merger or consolidation or the agreement giving rise
to the other corporate transaction if at the time of such merger, consolidation
or other transaction such optionee had been the holder of the number of shares
of Common Stock equal to the number of shares as to which the Option shall then
be so exercised.

    If a corporate transaction described in Section 424(a) of the Code which
involves the Company is to take place and there is to be no surviving
corporation while an Option remains in whole or in part unexercised, it shall be
cancelled by the Board of Directors as of the effective date of any such
corporate transaction but before the date each optionee shall be provided with a
notice of such cancellation and each optionee shall have the right to exercise
such Option in full (without regard to any limitations set forth in or imposed
pursuant to Paragraph 9 of the Plan) to the extent it is then still unexercised
during a 30-day period preceding the effective date of such corporate
transaction.

    For purposes of this Paragraph 12, "Current Market Price per share of Common
Stock" shall mean the closing price of a share of Common Stock on the principal
national securities exchange on which the Common Stock is listed or, if the
Common Stock is not so listed, the average bid and asked price of a share of
Common Stock as reported in the NASDAQ System, in each case on the trading day
immediately preceding the first trading day on which, as a result of the
establishment of a record date or otherwise, the trading price reflects that an
acquiror of

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                                                                          Page 8
<PAGE>

Common Stock in the public market will not participate in or receive the payment
of any applicable dividend or distribution.

    Except a hereinbefore expressly provided, the issue by the Company of shares
of Common Stock of any class, or securities convertible into shares of stock of
any class, for cash or property, or for labor or services either upon direct
sale or upon the exercise of rights or warrants to subscribe therefor, or upon
conversion of shares or obligations of the Company convertible into such shares
or other securities, shall not affect, and no adjustment by reason thereof shall
be made with respect to, the number or price of shares of Common Stock then
subject to outstanding Options.

    13. Amendment or Termination of Plan. The Board of Directors may modify,
revise or terminate the Plan at any time and from time to time; provided,
however, that without the further approval of the holders of a majority of the
shares of voting stock present in person or by proxy at a meeting of
stockholders, or if the provisions of the corporate charter, by-laws or
applicable state law prescribes a greater degree of stockholder approval for
this action, without the degree of stockholder approval thus required, the Board
of Directors may not (a) change the aggregate number of shares which may be
issued under Options pursuant to the provisions of the Plan; (b) reduce the
option price permitted for the Options; (c) extend the term during which an
option may be exercised or the termination date of the Plan; or (d) materially
increase any other benefits accruing to directors under the Plan or materially
modify the requirements as to eligibility for participation in the Plan unless,
in each such case, the Board of Directors of the Company shall have obtained an
opinion of legal counsel to the effect that stockholder approval of the
amendment is not required (i) by law, (ii) by the applicable rules and
regulations of, or any agreement with, any national securities exchange that the
Common Stock is then listed on or if the Common Stock is not so listed, the
rules and regulations, or any agreement with, the National Association of
Securities Dealers, Inc., and (iii) in order to make available to the optionee
with respect to any option granted under the Plan, the benefits of Rule 16b-3 of
the Rules and Regulations under the Securities Exchange Act of 1934, or any
similar or successor rule. In addition, the terms of the Plan relating to the
number of shares that may be subject to an Option, the times at which Options
shall be granted, and the means by which the Option Price for Options granted is
to be determined shall not be amended more than once every six months, other
than to comport with changes in the Code, the Employee Retirement Income
Security Act or the rules thereunder.

    14. Written Agreement. Each Option granted hereunder shall be embodied in a
written option agreement, which shall be subject to the terms and conditions
prescribed above, and shall be signed by the optionee and by the appropriate
officer of the Company for and in the name and on behalf of the Company. Such an
option agreement shall contain such other provisions as the Committee in its
discretion shall deem advisable.

    15. Indemnification of Committee. The Company shall indemnify each present
and future member of the Committee against, and each member of the Committee
shall be entitled without further act on his part to indemnity from the Company
for, all expenses (including the amount of judgments and the amount of approved
settlements made with a view to the curtailment of costs of litigation, other
than amounts paid to the Company itself) reasonably incurred by him in

--------------------------------------------------------------------------------
                                                                          Page 9
<PAGE>

connection with or arising out of any action, suit or proceeding in which he may
be involved by reason of his being or having been a member of the Committee,
whether or not he continues to be such member of the Committee at the time of
incurring such expenses; provided, however, that such indemnity shall not
include any expenses incurred by any such member of the Committee (a) in respect
of matters as to which he shall be finally adjudged in any such action, suit or
proceeding to have been guilty of gross negligence or willful misconduct in the
performance of his duty as such member of the Committee, or (b) in respect of
any matter in which any settlement is effected, to an amount in excess of the
amount approved by the Company on the advice of its legal counsel; and provided
further, that no right of indemnification under the provisions set forth herein
shall be available to or enforceable by any such member of the Committee unless,
within sixty (60) days after institution of any such action, suit or proceeding,
he shall have offered the Company, in writing, the opportunity to handle and
defend same at its own expense. The foregoing right of indemnification shall
inure to the benefit of the heirs, executors or administrators of each such
member of the Committee and shall be in addition to all other rights to which
such member of the Committee may be entitled to as a matter of law, contract, or
otherwise. Nothing in this Section 15 shall be construed to limit or otherwise
affect any right to indemnification, or payment of expense, or any provisions
limiting the liability of any officer or director of the Company or any member
of the Committee, provided by law, the Certificate of Incorporation of the
Company or otherwise.

    16. Effective Date of Plan. The Plan shall be deemed to have been adopted
and effective on December 19, 1995.

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                                                                         Page 10

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