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                                                                   Exhibit 10.23

                    AMENDED AND RESTATED EMPLOYMENT AGREEMENT

         AGREEMENT dated as of the 19th day of February, 2003 between Barr
Laboratories, Inc., a New York corporation having its principal executive
offices at 300 Corporate Drive, Building #10, Bradley Corporate Park, Blauvelt,
New York 10913 (the "Company"), and Salah U. Ahmed (the "Employee").

                                   WITNESSETH:

         WHEREAS, the Company and the Employee entered into an employment
agreement dated as of February 7, 2001, the term of which is scheduled to expire
on February 7, 2004 ("the Employment Agreement"); and

         WHEREAS, the Company and the Employee wish to amend and restate the
Employment Agreement in its entirety;

         NOW, THEREFORE, the Company and the Employee hereby agree that,
effective as of February 19, 2003, the Employment Agreement is amended and
restated in its entirety to read as follows:

         1.       Employment. The Company agrees to employ the Employee, and the
Employee agrees to remain in the employ of the Company, during the term of this
Agreement on the terms and conditions hereafter set forth.

         2.       Term. The term of this Agreement shall commence on February
19, 2003, (the "Commencement Date") and shall terminate at the close of business
on the third anniversary of the Commencement Date unless sooner terminated in
accordance with the terms of this Agreement or extended as hereinafter provided.
The term of this Agreement shall be extended, without further action by the
Company or the Employee, on the date (the "Extension Effective Date") which is
six months before the third anniversary of the Commencement Date and on the date
(also an "Extension Effective Date") which is six months before each subsequent
anniversary of the Commencement Date, for successive periods of twelve months
each, unless either party shall have given written notice to the other party, in
the manner set forth in paragraph 13(e) or (f) below, prior to the Extension
Effective Date in question, that the term of this Agreement that is in effect at
the time such written notice is given is not to be extended or further extended,
as the case may be. Examples that illustrate the intended operation of the
preceding sentence appear in the Appendix to this Agreement.

         3.       Positions and Responsibilities; Place of Performance.

                  (a)      Throughout the term of this Agreement, the Employee
agrees to remain in the employ of the Company, and the Company agrees to employ
the Employee, as its Senior Vice President, Research & Development, reporting to
the Chief Executive Officer of the Company (the "CEO"), and /or the President
and Chief Operations Officer of the Company (the "COO"), as the CEO or COO may
direct. As the Senior Vice President, Research & Development of the Company, the
Employee shall be responsible

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for managing and supervising, and shall have responsibility for the day-to-day
conduct of, the research and development activities of the Company and its
subsidiaries, other than new proprietary drug discovery and development
activities, subject to the authority of the Board of Directors of the Company
(the "Board) and the CEO and the COO, and shall have all of the powers,
authority, duties and responsibilities he has had prior to the Commencement Date
and all of the powers, authority, duties and responsibilities usually incident
to the position and role of Senior Vice President, Research & Development (other
than with respect to new proprietary drug discovery and development activities),
and shall perform such other reasonable duties, consistent with the position of
Senior Vice President, Research & Development, as may lawfully be assigned to
him by the Board or the CEO or the COO.

                  (b)      In connection with his employment by the Company, the
Employee shall be based at the principal executive offices of the Company in the
greater New York City metropolitan area, and he agrees to travel, to the extent
reasonably necessary to perform his duties and obligations under this Agreement,
to Company facilities and other destinations elsewhere at the Company's expense.

                  (c)      During the term of this Agreement, the Employee shall
serve the Company on an exclusive basis and shall devote all his business time,
attention, skill and efforts to the faithful performance of his duties
hereunder; provided that the Employee may engage in community service and
charitable activities that do not materially interfere with the performance of
his duties and responsibilities hereunder.

         4.       Compensation. For all services rendered by the Employee in any
capacity during the term of this Agreement, and for his undertakings with
respect to confidential information, non-solicitation and disparaging remarks
set forth in sections 6 and 7 below, the Employee shall be entitled to the
following:

                  (a)      a salary, payable in installments not less frequent
than monthly, at the annual rate of two hundred and fifty thousand dollars
($250,000), with such increases in such rate, if any, as the Compensation
Committee of the Board may approve from time to time during the term of this
Agreement in accordance with the Company's regular administrative practices
applicable to senior officers from time to time during the term of this
Agreement (the annual salary rate as increased from time to time during the term
of this Agreement being hereafter referred to as the "Base Salary");

                  (b)      participation in the Company's annual executive
incentive or bonus plan as in effect from time to time, with the opportunity to
receive an award in accordance with the terms and conditions of such plan, for
each fiscal year of the Company that commences or terminates during the term of
this Agreement, of up to 40% of the Base Salary earned during such year (or such
higher percentage as the Board or a committee of the Board may allow from time
to time during the term of this Agreement), it being understood that any award
for the fiscal year of the Company in which the term of this Agreement
terminates pursuant to the terms hereof shall be prorated based on the portion
of such fiscal year that coincides with the term of this Agreement and shall be

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made at the same time as awards (if any) are made to other participants with
respect to such fiscal year;

                  (c)      participation in the Company's stock incentive plan
as from time to time in effect, subject to the terms and conditions of such
plan;

                  (d)      the business and personal use of an automobile at
Company expense including, without limitation, payment or reimbursement of
automobile insurance and maintenance expenses in accordance with the Company's
automobile policy applicable to senior officers on the Commencement Date; and

                  (e)      participation in all Company health, welfare, savings
and other employee benefit and fringe benefit plans (including vacation pay
plans or policies and life and disability insurance plans) in which other senior
officers of the Company participate during the term of this Agreement, subject
in all events to the terms and conditions of such plans as in effect from time
to time. Nothing in this paragraph (e) shall preclude the Company from amending
or terminating any such plan at any time. The plans covered by this paragraph
(e) shall not include the annual incentive or stock incentive plans, which are
covered by paragraphs (b) and (c) above.

         5.       Termination of Employment.

                  (a)      Termination by the Company without Good Cause or by
the Employee for Good Reason.

                           (i)      If the Employee's employment with the
Company is terminated by the Company without Good Cause or is terminated by the
Employee for Good Reason during the term of this Agreement and other than at or
after the expiration of the term of this Agreement as the same may have been
extended in accordance with the provisions of section 2 above (any such
employment termination being hereafter referred to as a "Compensable
Termination"), the Company shall pay the Employee the portion of his Base Salary
accrued through the date of the Compensable Termination and any other amounts to
which he is entitled by law or pursuant to the terms of any compensation or
benefit plan or arrangement in which he participated prior to the Compensable
Termination and, in addition, subject to compliance by the Employee with the
provisions of sections 6 and 7 below, relating to confidential information,
non-solicitation and disparaging remarks, the Company shall, as liquidated
damages or severance pay or both (whichever characterization(s) will serve to
validate the payments), and as additional consideration for the Employee's
undertakings under sections 6 and 7 below, pay the Employee the following:

                                    (A)      his annual bonus for the fiscal
year of the Company preceding the fiscal year of the Company in which the
Compensable Termination occurs, if unpaid at the time of the Compensable
Termination, the amount of such bonus to be determined by the Compensation
Committee of the Board on a basis consistent with its prior bonus determinations
with respect to the Employee or, in the event a Change in Control or Potential
Change in Control (as defined in section 11 below) occurred before

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the Compensable Termination, consistent with its bonus determinations with
respect to the Employee prior to the Change in Control or Potential Change in
Control; and

                                    (B)      a prorated annual bonus for the
fiscal year of the Company in which the Compensable Termination occurs, such
prorated annual bonus to be determined by multiplying the "Applicable Average
Bonus" as defined below in this subparagraph 5(a)(i)(B) by a fraction the
numerator of which shall be the number of days elapsed in such fiscal year
through (and including) the date on which the Compensable Termination occurs and
the denominator of which shall be the number 365. For purposes of this
Agreement, the "Applicable Average Bonus" means the higher of (I) the average
annual bonus (including any deferred bonus) awarded to the Employee during the
three year period immediately preceding the Compensable Termination, or (II) the
average annual bonus (including any deferred bonus) awarded to the Employee
during the three fiscal years of the Company preceding the fiscal year in which
the Compensable Termination occurs; provided that, if the Compensable
Termination occurs after a Change in Control or Potential Change in Control, the
Applicable Average Bonus shall not be less than the average annual bonus
(including any deferred bonus) awarded to the Employee during the three years
preceding the date on which the Change in Control or Potential Change in Control
occurred; and

                                    (C)      an amount of money (the "Severance
Payment") equal to two (2) times the Employee's "Annual Cash Compensation" as
hereafter defined, unless the Severance Payment is payable solely on account of
the Employee's resignation for Good Reason pursuant to subparagraph 5(d)(v)
below (relating to the Company's giving the Employee notice of non-extension),
in which case the Severance Payment shall be equal to one and one-quarter (1
1/4) times the Employee's "Annual Cash Compensation" as hereafter defined.
Except as otherwise provided hereafter in this subparagraph 5(a)(i)(C),
seventy-five percent (75%) of the Severance Payment shall be paid in a lump sum
within ten days after the date of the Compensable Termination. The twenty-five
percent (25%) balance of the Severance Payment shall be paid in six (6) equal
monthly installments one of which shall be paid at the end of each of the first
six (6) months after the date of the Compensable Termination, provided, in the
case of each of such six installments, that the Employee has not accepted
full-time or regular part-time employment with or regularly served as a
consultant to a for-profit pharmaceutical company prior to the date for payment
of such installment, it being understood and agreed that the foregoing condition
shall not be violated by the Employee's serving as a member of a board of
directors of a for-profit pharmaceutical company or by his performing consulting
services on an ad hoc basis for such a company. If a Change in Control or
Potential Change in Control as defined in section 11 below occurs (either before
or after the Compensable Termination), the Severance Payment (or, in the case of
a Change in Control or Potential Change in Control that occurs after the
Compensable Termination, any portion thereof that remains unpaid at the time
such Change in Control or Potential Change in Control occurs) shall be paid in a
lump sum within ten days after the Compensable Termination (or, in the case of a
Change in Control or Potential Change in Control that occurs after the
Compensable Termination, within ten days after the Change in Control or
Potential Change in Control occurs), and the two preceding sentences of this
subparagraph shall not apply. In addition, if the Severance Payment is

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payable solely on account of the Employee's resignation for Good Reason pursuant
to subparagraph 5(d)(v) below (relating to the Company's giving the Employee
notice of non-extension), the Severance Payment shall be paid in a lump sum
within ten days after the Employee resigns for such Good Reason, and the second
and third preceding sentences of this subparagraph shall not apply. During the
18 month period following a Compensable Termination, the Company shall also
provide the Employee with COBRA coverage at its expense. For purposes of this
section 5, the Employee's "Annual Cash Compensation" shall mean the sum of (I)
the Employee's highest Base Salary (i.e., one year's salary at its highest
rate), plus (II) the "Applicable Average Bonus" as defined in subparagraph
5(a)(i)(B) above.

                           (ii)     If the term of this Agreement as the same
may have been extended in accordance with the provisions of section 2 above is
not extended or further extended because the Company gives written notice of
non-extension to the Employee as provided in section 2 above, and the Company
does not have Good Cause for termination of the Employee's employment at the
time of giving such notice, and the Employee does not thereafter resign for Good
Reason during the term of this Agreement as permitted by paragraph 5(d)(v)
below, then the Company, subject to fulfillment by the Employee of his
obligations under this Agreement during the balance of the term and his
compliance with the provisions of sections 6 and 7 below, relating to
confidential information, non-solicitation and disparaging remarks, shall, as
non-renewal compensation, and as additional consideration for the Employee's
undertakings under this Agreement including sections 6 and 7 below, pay the
Employee an amount of money (the "Non-Renewal Payment") equal to the Employee's
Annual Cash Compensation as defined in subparagraph 5(a)(i)(C) above, in
addition to any other amounts to which the Employee may be entitled hereunder
(including without limitation his annual bonus pursuant to paragraph 4(b) above
for the fiscal year of the Company in which his employment terminates and any
amounts to which he may be entitled under section 8, 9 or 10 below) or by law or
pursuant to the terms of any compensation or benefit plan or arrangement in
which he participated before his employment terminated. The Non-Renewal Payment
shall be paid in a lump sum within ten days after the date on which the
Employee's employment terminates. During the 18 month period following the
termination of his employment, the Company shall also provide the Employee with
COBRA coverage at its expense.

                           (iii)    The foregoing provisions of (including any
payments under) this paragraph 5(a) shall be in lieu of any severance pay that
may be payable under any plan or practice of the Company, but shall be in
addition to (and not in lieu of) any payments to which the Employee may be
entitled under sections 8, 9 and 10 below. Subparagraphs 5(a)(i)(C) and 5(a)(ii)
above are intended to be mutually exclusive, and in no event shall such
subparagraphs, either individually or collectively, be construed to require the
Company to pay an amount of money in excess of two times the Employee's Annual
Cash Compensation under such subparagraphs, either individually or collectively,
in addition to the 18 months of COBRA coverage provided for therein. The
Employee shall not be required to mitigate the amount of any payment or benefit
provided for in this Agreement (including but not limited to any payment
provided for above in this paragraph 5(a)) by seeking other employment or
otherwise, nor shall any compensation

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earned by the Employee in other employment or otherwise reduce the amount of any
payment or benefit provided for in this Agreement.

                  (b)      Termination by the Company for Good Cause or by the
Employee without Good Reason. If, during the term of this Agreement, the
Employee's employment by the Company is terminated by the Company for Good Cause
or by the Employee without Good Reason, the Employee shall not be entitled to
receive any compensation under section 4 above accruing after the date of such
termination or any payment under paragraph 5(a) above. The provisions of this
paragraph 5(b) shall be in addition to, and not in lieu of, any other rights and
remedies the Company may have at law or in equity or under any other provision
of this Agreement in respect of such termination of employment. However, if
during the term of this Agreement the Employee's employment is terminated by the
Employee without Good Reason and the Employee gives the Company at least 120
days' advance notice of such termination, then the Employee shall not have any
obligation or liability to the Company under this Agreement in respect of such
termination of employment, but his obligations under section 6 and 7 hereof
shall not be affected by such termination of employment.

                  (c)      Good Cause Defined. For purposes of this Agreement,
the Company shall have "Good Cause" to terminate the Employee's employment
during the term of this Agreement only if:

                           (i)      the Employee fails to substantially perform
his duties hereunder for any reason or fails to devote substantially all his
business time exclusively to the affairs of the Company, and such failure is not
discontinued within a reasonable period of time, in no event to exceed 30 days,
after the Employee receives written notice from the Company of such failure; or

                           (ii)     the Employee commits an act of dishonesty
resulting or intended to result directly or indirectly in gain or personal
enrichment at the expense of the Company; or

                           (iii)    the Employee is grossly negligent or engages
in willful misconduct or insubordination in the performance of his duties
hereunder; or

                           (iv)     the Employee materially breaches his
obligations under section 6 or paragraph 7(a) below, relating to confidential
information and non-solicitation.

Any foregoing provision of this paragraph 5(c) to the contrary notwithstanding,
the Company shall not have "Good Cause" to terminate the Employee's employment
within three years after a Change in Control or Potential Change in Control (as
such terms are defined in section 11 below) unless (A) the Employee's act or
omission is willful and has a material adverse effect upon the Company, (B) the
Board of Directors gives the Employee (I) written notice warning of its
intention to terminate the Employee for Good Cause if the specified act or
omission alleged to constitute Good Cause is not discontinued and, if curable,
cured, and (II) a reasonable opportunity after receipt of such

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written notice, but in no event less than two weeks, to discontinue and, if
curable, cure the conduct alleged to constitute Good Cause, and (C) the Employee
fails to discontinue and, if curable, cure the act or omission in question;
provided that clauses (B) and (C) of this sentence shall not apply with respect
to misconduct on the part of the Employee that constitutes a felony in the
jurisdiction in which the Employee engages in such misconduct, and, provided
further, that this sentence shall not apply to conduct involving moral
turpitude. For all purposes of this Agreement, no act, or failure to act, on the
Employee's part shall be deemed "willful" unless done, or omitted to be done, by
him intentionally and in bad faith (i.e., without reasonable belief that his
action or omission was in furtherance of the interests of the Company or a
subsidiary of the Company).

                  (d)      Good Reason Defined. For purposes of this Agreement,
the Employee shall have "Good Reason" to terminate his employment during the
term of this Agreement only if:

                           (i)      the Company fails to pay or provide any
amount or benefit that the Company is obligated to pay or provide under section
4 above or section 8, 9 or 10 below and the failure is not remedied within 30
days after the Company receives written notice from the Employee of such
failure; or

                           (ii)     the Company assigns the Employee duties,
responsibilities or reporting relationships not contemplated by section 3 above
without his consent, or limits his duties or responsibilities or power or
authority contemplated by section 3 above in any respect materially detrimental
to him, and in either case the situation is not remedied within 30 days after
the Company receives written notice from the Employee of the situation; or

                           (iii)    he is removed from, or not elected or
reelected to, the office, title or position of Senior Vice President, Research &
Development of the Company, and the Company does not have Good Cause for doing
so; or

                           (iv)     the Company relocates his office outside of
either the Company's principal executive offices or the greater New York City
metropolitan area without his written consent (given in a personal rather than
representative capacity) and the situation is not remedied within 30 days after
the Company receives written notice from the Employee of the situation; or

                           (v)      the Company gives the Employee written
notice, in the manner set forth in paragraph 13(f) below, prior to any Extension
Effective Date, that the term of this Agreement that is in effect at the time
such written notice is given is not to be extended or further extended, as the
case may be; provided that the giving of such written notice to the Employee
shall constitute Good Reason only if and when the Employee shall have performed
such of his duties and responsibilities for such period of time, in no event to
exceed ninety (90) days after the giving of such notice, as the CEO, the COO or
the Board may reasonably request in writing to transition his duties and
responsibilities; or

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                           (vi)     a Change in Control occurs and as a result
thereof either (A) equity securities of the Company cease to be publicly-traded,
or (B) the Employee is not elected or designated to serve as the sole Senior
Vice President, Research & Development (other than new proprietary drug
discovery and development) of the surviving company; or

                           (vii)    a Change in Control or Potential Change in
Control occurs and (A) the dollar value of the stock optioned to the Employee
annually thereafter is less than the average annual dollar value of the stock
that was optioned to the Employee during the four years prior to the Change in
Control or Potential Change in Control, or (B) the material terms of such
options (including without limitation vesting schedules) are less favorable to
the Employee than the material terms of the options that were granted to the
Employee during the four years prior to the Change in Control or Potential
Change in Control, and in either case (A) or (B) the situation is not remedied
within 30 days after the Company receives written notice from the Employee of
the situation.

In no event shall the Employee's continued employment after any of the foregoing
constitute his consent to the act or omission in question, or a waiver of his
right to terminate his employment for Good Reason hereunder on account of such
act or omission.

         6.       Confidential Information. The Employee agrees not to disclose,
either while in the Company's employ or at any time thereafter, to any person
not employed by the Company, or not engaged to render services to the Company,
except with the prior written consent of an authorized officer of the Company or
as necessary or appropriate for the performance of his duties hereunder, any
confidential information obtained by him while in the employ of the Company,
including, without limitation, information relating to any of the inventions,
processes, formulae, plans, devices, compilations of information, research,
methods of distribution, suppliers, customers, client relationships, marketing
strategies or trade secrets of the Company or any subsidiary thereof; provided,
however, that this provision shall not preclude the Employee from use or
disclosure of information known generally to the public or of information not
considered confidential by persons engaged in the businesses conducted by the
Company or any subsidiary thereof, or from disclosure required by law or court
order. The Employee also agrees that upon leaving the Company's employ he will
not take with him, without the prior written consent of an authorized officer of
the Company, and he will surrender to the Company, any record, list, drawing,
blueprint, specification or other document or property of the Company or any
subsidiary thereof, together with any copy or reproduction thereof, mechanical
or otherwise, which is of a confidential nature relating to the Company or any
subsidiary thereof, or without limitation, relating to its or their methods of
distribution, suppliers, customers, client relationships, marketing strategies
or any description of any formulae or secret processes, or which was obtained by
him or entrusted to him during the course of his employment with the Company.

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         7.       Restrictive Covenants

                  (a)      Non-Solicitation. Employee covenants and agrees that,
during his employment by the Company and during the one year period immediately
following the termination of his employment with the Company for any reason
(including, without limitation, a termination of employment by the Company
without cause and a voluntary termination of employment by the Employee, in
either case whether during the term of this Agreement, at the expiration of the
term of this Agreement or at any time thereafter), he will not solicit or
attempt to persuade any employee of the Company, its subsidiaries or affiliates
(except the Employee's personal secretary or administrative assistant), or any
other person who performs services for the Company, its subsidiaries or
affiliates at the time the Employee's employment terminates or at any time
within one year thereafter, to terminate or reduce or refrain from engaging in
his or her employment or other service relationship with the Company, its
subsidiaries or affiliates; provided, however, that responding to inquiries from
any such employees or other persons that are not initiated by the Employee, and
subsequently hiring such employees or other persons following the termination of
their employment with the Company, its subsidiaries and affiliates shall be
permitted.

                  (b)      Specific Enforcement. Employee recognizes and agrees
that, by reason of his knowledge, experience, skill and abilities, his services
are extraordinary and unique, that the breach or attempted breach of any of the
restrictions set forth above in this section 7 will result in immediate and
irreparable injury for which the Company will not have an adequate remedy at
law, and that the Company shall be entitled to a decree of specific performance
of those restrictions and to a temporary and permanent injunction enjoining the
breach thereof, and to seek any and all other remedies to which the Company may
be entitled, including, without limitation, monetary damages, without posting
bond or furnishing security of any kind.

                  (c)      Restrictions Reasonable. Employee specifically and
expressly represents and warrants that (i) he has reviewed and agreed to the
restrictive covenants contained in this section 7 and their contemplated
operation after receiving the advice of counsel of his choosing; (ii) he
believes, after receiving such advice, that the restrictive covenants and their
contemplated operation are fair and reasonable; (iii) he will not seek or
attempt to seek to have the restrictive covenants declared invalid, and, after
receiving the advice of counsel, expressly waives any right to do so; and (iv)
if the full breadth of any restrictive covenant and/or its contemplated
operation shall be held in any fashion to be too broad, such covenant or its
contemplated operation, as the case may be, shall be interpreted in a manner as
broadly in favor of the beneficiary of such covenant as is legally permissible.
Employee recognizes and agrees that the restrictions on his activities contained
in this section 7 are required for the reasonable protection of the Company and
its investments; and that the restriction on his activities set forth in
paragraph 7(a) will not deprive the Employee of the ability to earn a
livelihood.

                  (d)      Non-Disparagement. Employee covenants and agrees
that, during the one year period immediately following the termination of his
employment with the Company for any reason (including, without limitation, a
termination of employment by

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the Company without cause and a voluntary termination of employment by the
Employee, in either case whether during the term of this Agreement, at the
expiration of the term of this Agreement or at any time thereafter), he will not
make disparaging remarks about the Company, its subsidiaries or affiliates or
any of their officers, directors or employees, unless required by law or
reasonably necessary to assert or defend his position in a bona fide dispute
arising out of or relating to this Agreement or the breach thereof.

                  (e)      Effect on Termination Payments. The Employee
recognizes and agrees that the Company shall not be obligated to make any
payments provided for in paragraph 5(a) above if the Employee violates the
provisions of section 6 or paragraph 7(a) or 7(d) above during the one year
period immediately following the termination for any reason of his employment
with the Company. In addition, the Employee recognizes and agrees that, if the
Employee violates such provisions, the Company may recoup any payments the
Company may have theretofore made pursuant to paragraph 5(a) above and any
payments the Company may thereafter make under paragraph 5(a). The foregoing
provisions of this paragraph 7(e) shall be in addition to and not by way of
limitation of any other rights and remedies the Company may have in respect of
the violation in question.

         8.       Indemnification

         To the fullest extent permitted by applicable law, the Company shall
indemnify, defend and hold harmless the Employee from and against any and all
claims, demands, actions, causes of action, liabilities, losses, judgments,
fines, costs and expenses (including reasonable attorneys' fees and settlement
expenses) arising from or relating to his service or status as an officer,
director, employee, agent or representative of the Company or any subsidiary of
the Company or in any other capacity in which the Employee serves or has served
at the request of, or for the benefit of, the Company or its subsidiaries. The
Company's obligations under this section 8 shall be in addition to, and not in
derogation of, any other rights the Employee may have against the Company to
indemnification or advancement of expenses, whether by statute, contract or
otherwise.

         9.       Certain Additional Payments by the Company

                  (a)      Anything in this Agreement (other than the second
sentence of this paragraph 9(a)) to the contrary notwithstanding, in the event
it shall be determined that any payment or distribution by the Company to or for
the benefit of the Employee (whether paid or payable or distributed or
distributable pursuant to the terms of this Agreement or otherwise, but
determined without regard to any additional payments required under this section
9) (a "Payment"), would be subject to the excise tax imposed by Section 4999 of
the United States Internal Revenue Code (the "Code") or any interest or
penalties are incurred by the Employee with respect to such excise tax (such
excise tax, together with any such interest and penalties, are hereinafter
collectively referred to as the "Excise Tax"), then the Employee shall be
entitled to receive an additional payment (a "Gross-Up Payment") in an amount
such that after payment by the Employee of all taxes and any benefits that
result from the deductibility by the Employee of such

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taxes (including, in each case, any interest or penalties imposed with respect
to such taxes), including, without limitation, any income taxes (and any
interest and penalties imposed with respect thereto) and Excise Tax imposed upon
the Gross-Up Payment, the Employee retains an amount of the Gross-Up Payment
equal to the Excise Tax imposed upon the Payments. However, if it shall be
determined that none of the Payments would be subject to the Excise Tax if the
total Payments were reduced in the aggregate by $25,000 or less, then in that
event the total Payments shall be reduced by the smallest amount (in no event to
exceed $25,000 in the aggregate) necessary to ensure that none of the Payments
will be subject to the Excise Tax. The decision as to which Payments shall be so
reduced shall be made by the Employee.

                  (b)      Subject to the provisions of paragraph 9(a) above and
9(c) below, all determinations required to be made under this section 9,
including whether and when a Gross-Up Payment is required and the amount of such
Gross-Up Payment and the assumptions to be utilized in arriving at such
determination, and whether Payments are to be reduced pursuant to the second
sentence of paragraph 9(a) above, shall be made by Deloitte & Touche or such
other certified public accounting firm as may be designated by the Employee (the
"Accounting Firm") which shall provide detailed supporting calculations both to
the Company and the Employee within 15 business days of the receipt of notice
from the Employee that there has been a Payment, or such earlier time as is
requested by the Company. In the event that the Accounting Firm is serving as
accountant or auditor for the individual, entity or group effecting the "change
in ownership or effective control" or "change in the ownership of a substantial
portion of assets" (within the meaning of Code section 280G(b)(2)(A)) that gives
rise to the Excise Tax, the Employee shall appoint another nationally recognized
accounting firm to make the determinations required hereunder (which accounting
firm shall then be referred to as the Accounting Firm hereunder). All fees and
expenses of the Accounting Firm shall be borne solely by the Company. Any
Gross-Up Payment, as determined pursuant to this section 9, shall be paid by the
Company to the Employee within five days of the receipt of the Accounting Firm's
determination. Any determination by the Accounting Firm shall be binding upon
the Company and the Employee. As a result of the uncertainty in the application
of Section 4999 of the Code at the time of the initial determination by the
Accounting Firm hereunder, it is possible that Gross-Up Payments which will not
have been made by the Company should have been made (an "Underpayment"),
consistent with the calculations required to be made hereunder. In the event
that the Company exhausts its remedies pursuant to paragraph 9(c) and the
Employee thereafter is required to make a payment of any Excise Tax, the
Accounting Firm shall determine the amount of the Underpayment that has occurred
and any such Underpayment, along with any penalty and interest imposed with
respect to such Underpayment, shall be promptly paid by the Company to or for
the benefit of the Employee.

                  (c)      The Employee shall notify the Company in writing of
any claim by the Internal Revenue Service that, if successful, would require
either the payment by the Company of the Gross-Up Payment or the reduction of
Payments pursuant to the second sentence of paragraph 9(a) above. Such
notification shall be given as soon as practicable but no later than ten
business days after the Employee is informed in writing of such claim and shall
apprise the Company of the nature of such claim and the date on which

                                       11

<PAGE>

such claim is requested to be paid. The Employee shall not pay such claim prior
to the expiration of the 30-day period following the date on which it gives such
notice to the Company (or such shorter period ending on the date that any
payment of taxes with respect to such claim is due). If the Company notifies the
Employee in writing prior to the expiration of such period that it desires to
contest such claim, the Employee shall:

                           (i)      give the Company any information reasonably
requested by the Company relating to such claim,

                           (ii)     take such action in connection with
contesting such claim as the Company shall reasonably request in writing from
time to time, including, without limitation, accepting legal representation with
respect to such claim by an attorney reasonably selected by the Company,

                           (iii)    cooperate with the Company in good faith in
order effectively to contest such claim, and

                           (iv)     permit the Company to participate in any
proceedings relating to such claim;

provided, however, that the Company shall bear and pay directly all costs and
expenses (including additional interest and penalties) incurred in connection
with such contest and shall indemnify and hold the Employee harmless, on an
after-tax basis, for any Excise Tax or income tax (including interest and
penalties with respect thereto) imposed as a result of such representation and
payment of costs and expenses. Without limitation on the foregoing provisions of
this paragraph 9(c), the Company shall control all proceedings taken in
connection with such contest and, at its sole option, may pursue or forgo any
and all administrative appeals, proceedings, hearings and conferences with the
taxing authority in respect of such claim and may, at its sole option, either
direct the Employee to pay the tax claimed and sue for a refund or contest the
claim in any permissible manner, and the Employee agrees to prosecute such
contest to a determination before any administrative tribunal, in a court of
initial jurisdiction and in one or more appellate courts, as the Company shall
determine, provided, however, that if the Company directs the Employee to pay
such claim and sue for a refund, the Company shall, if permissible under Section
402 of the Sarbanes-Oxley Act of 2002, advance the amount of such payment to the
Employee on an interest-free basis or, if such an advance is not permissible
thereunder, pay the amount of such payment to the Employee as additional
compensation, and shall indemnify and hold the Employee harmless, on an
after-tax basis, from any Excise Tax or income tax (including interest or
penalties with respect thereto) imposed with respect to such advance or
additional compensation; and further provided that any extension of the statute
of limitations relating to payment of taxes for the taxable year of the Employee
with respect to which such contested amount is claimed to be due is limited
solely to such contested amount. Furthermore, the Company's control of the
contest shall be limited to issues with respect to which a Gross-Up Payment
would be payable hereunder and the Employee shall be entitled to settle or
contest, as the case may be, any other issue raised by the Internal Revenue
Service or any other taxing authority.

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<PAGE>

                  (d)      If, after the receipt by the Employee of an amount
advanced or paid by the Company pursuant to paragraph 9(a) or 9(c), the Employee
becomes entitled to receive any refund with respect to such claim, the Employee
shall (subject to the Company's complying with the requirements of paragraph
9(c)) promptly pay to the Company the amount of such refund (together with any
interest paid or credited thereon after taxes applicable thereto). If, after the
receipt by the Employee of an amount advanced by the Company pursuant to
paragraph 9(c), a determination is made that the Employee shall not be entitled
to any refund with respect to such claim and the Company does not notify the
Employee in writing of its intent to contest such denial of refund prior to the
expiration of 30 days after such determination, then such advance shall be
forgiven and shall not be required to be repaid and the amount of such advance
shall offset, to the extent thereof, the amount of Gross-Up Payment required to
be paid.

         10.      Certain Enforcement Matters

                  (a)      If, after a Change in Control or Potential Change in
Control, a dispute arises (i) with respect to this Agreement or the breach
thereof, or (ii) with respect to the Employee's or the Company's rights or
obligations under this Agreement, including but not limited to any such dispute
between the Employee and the Company, the Company shall pay or reimburse the
Employee for all reasonable costs and expenses (including court costs,
arbitrators' fees and reasonable attorneys' fees and disbursements) the Employee
incurs in connection with such dispute, including without limitation costs and
expenses he incurs to obtain payment or otherwise enforce his rights under this
Agreement, or to obtain payment of costs and expenses due under this paragraph
10(a). In addition, the Company shall pay the Employee such additional amount (a
"Gross Up") as will be sufficient, after the Employee pays his tax liability
with respect to the Gross Up from the Gross Up, to pay all of his federal, state
and local tax liability with respect to any costs and expenses that are paid by
the Company pursuant to this paragraph 10(a). The Company shall promptly pay or
reimburse the Employee for all such costs and expenses as he incurs them, upon
presentation of reasonable documentation of such costs and expenses, and shall
promptly pay the related Gross Up as and when it pays or reimburses costs and
expenses. The Employee shall not be obligated to repay any such costs, expenses
or Gross Up unless it is finally determined by the trier of fact in a
non-appealable judicial or arbitral decision or ruling (as applicable) that the
Employee's principal positions with respect to the principal matter(s) in
dispute were unreasonable and pursued in bad faith.

                  (b)      Any payments to which the Employee may be entitled
under this Agreement, including, without limitation, under section 5, 8, 9 or 10
hereof, shall be made forthwith on the applicable date(s) for payment specified
in this Agreement. If for any reason the amount of any payment due to the
Employee cannot be finally determined on that date, such amount shall be
estimated on a good faith basis by the Company and the estimated amount shall be
paid no later than within 10 days after such date. As soon as practicable
thereafter, the final determination of the amount due shall be made and any
adjustment requiring a payment to or from the Employee shall be made as promptly
as practicable.

                                       13

<PAGE>

                  (c)      Any controversy or claim arising, after a Change in
Control or Potential Change in Control, out of or related to this Agreement or
the breach thereof, shall be settled by binding arbitration in the City of New
York, in accordance with the employment dispute arbitration rules of the
American Arbitration Association then in effect, and the arbitrator's decision
shall be binding and final and judgment upon the award rendered may be entered
in any court having jurisdiction thereof, except that the Employee may elect to
have any such controversy or claim settled by judicial determination in lieu of
arbitration by bringing a court action, if he is the plaintiff or, if he is not
the plaintiff, demanding such judicial determination within the time to answer
any complaint in any arbitration action that may be commenced.

         11.      Change in Control

                  (a)      The term "Change in Control" as used in this
Agreement means a change of control of the Company of a nature that would be
required to be reported in response to Item 6(e) of Schedule 14A of Regulation
14A promulgated under the Securities Exchange Act of 1934, as amended (the
"Exchange Act"), whether or not the Company is then subject to such reporting
requirement; provided that, whether or not any of the following events would
constitute a change of control of such a nature, a Change in Control shall be
deemed to occur for purposes of this Agreement if and when any of the following
events occur:

                           (i)      any "person" (as such term is used in
Sections 13(d) and 14(d)(2) of the Exchange Act), other than--

                                    (A) the Company,

                                    (B) a Subsidiary,

                                    (C) a trustee or other fiduciary holding
                           securities under an employee benefit plan of the
                           Company or a Subsidiary, or

                                    (D) an underwriter engaged in a distribution
                           of Company stock to the public with the Company's
                           written consent,

becomes the beneficial owner (as defined in Rule 13d-3 under the Exchange Act),
directly or indirectly, of Voting Securities that represent more than thirty
percent (30%) of the combined voting power of the then outstanding Voting
Securities. However, if the "person" in question is an institutional investor
whose investment in Voting Securities is purely passive when such person becomes
such a more than thirty percent beneficial owner of Voting Securities, then such
event (i.e., such person's becoming a more than thirty percent beneficial owner
of Voting Securities) shall not be deemed to constitute a Change in Control
under this subparagraph 11(a)(i) for so long as (and only for so long as) such
person's investment in Voting Securities remains purely passive; or

                           (ii)     the stockholders of the Company approve a
merger, consolidation, recapitalization or reorganization of the Company or a
Subsidiary, reverse split of any class of Voting Securities, or an acquisition
of securities or assets by the Company or a Subsidiary, or consummation of any
such transaction if stockholder

                                       14

<PAGE>

approval is not obtained, other than (A) any such transaction in which the
holders of outstanding Voting Securities immediately prior to the transaction
receive, with respect to such Voting Securities (or, in the case of a
transaction in which the Company is the surviving corporation or a transaction
involving a Subsidiary, retain), voting securities of the surviving or
transferee entity representing more than fifty percent (50%) of the total voting
power outstanding immediately after such transaction, with the voting power of
each such continuing holder relative to other such continuing holders not
substantially altered in the transaction, or (B) any such transaction which
would result in a Related Party beneficially owning more than 50 percent of the
voting securities of the surviving entity outstanding immediately after such
transaction; or

                           (iii)    the stockholders of the Company approve a
plan of complete liquidation of the Company or an agreement for the sale or
disposition by the Company of all or substantially all of the Company's assets
other than any such transaction which would result in a Related Party owning or
acquiring more than 50 percent of the assets owned by the Company immediately
prior to the transaction; or

                           (iv)     the persons who were members of the Board of
Directors of the Company immediately before a tender or exchange offer for
shares of Common Stock by any person other than the Company or a Related Party,
or before a merger or consolidation of the Company or a Subsidiary, or contested
election of the Board of Directors of the Company, or before any combination of
such transactions, cease to constitute a majority of the Board of Directors of
the Company as a result of such transaction or transactions.

                  (b)      For purposes of paragraph 11(a) above:

                           (i)      the term "Related Party" shall mean (A) a
Subsidiary, (B) an employee or group of employees of the Company or any
Subsidiary, (C) a trustee or other fiduciary holding securities under an
employee benefit plan of the Company or any Subsidiary, or (D) a corporation or
other form of business entity owned directly or indirectly by the stockholders
of the Company in substantially the same proportion as their ownership of Voting
Securities;

                           (ii)     the term "Subsidiary" means a corporation or
other form of business association of which shares (or other ownership
interests) having more than 50% of the voting power are, or in the future
become, owned or controlled, directly or indirectly, by the Company; and

                           (iii)    the term "Voting Securities" shall mean any
securities of the Company which carry the right to vote generally in the
election of directors.

                  (c)      For purposes of this Agreement, a "Potential Change
in Control" means that (i) the Company enters into an agreement, the
consummation of which would result in the occurrence of a Change of Control; or
(ii) the Board adopts a resolution to the effect that, for purposes of this
Agreement, a potential change in control of the Company has occurred.

                                       15

<PAGE>

         12.      Severability; Survival

                  (a)      In the event that any provision of this Agreement
shall be determined to be invalid or unenforceable for any reason, the remaining
provisions of this Agreement not so invalid or unenforceable shall be unaffected
thereby and shall remain in full force and effect to the fullest extent
permitted by law; and

                  (b)      Any provision of this Agreement which may for any
reason be invalid or unenforceable in any jurisdiction shall remain in effect
and be enforceable in any jurisdiction in which such provision shall be valid
and enforceable.

                  (c)      The provisions of sections 6, 7, 8, 9 and 10 of this
Agreement, and any other provision of this Agreement which is intended to apply,
operate or have effect after the expiration or termination of the term of this
Agreement, or at a time when the term of this Agreement may have expired or
terminated, shall survive the expiration or termination of the term of this
Agreement for any reason.

         13.      General Provisions

                  (a)      No right or interest to or in any payments to be made
under this Agreement shall be subject to anticipation, alienation, sale,
assignment, encumbrance, pledge, charge or hypothecation or to execution,
attachment, levy or similar process, or assignment by operation of law. All
payments to be made by the Company hereunder shall be subject to the withholding
of such amounts as the Company may determine it is required to withhold under
the laws or regulations of any governmental authority, whether foreign, federal,
state or local.

                  (b)      To the extent that the Employee acquires a right to
receive payments from the Company under this Agreement, such right shall be no
greater than the right of an unsecured general creditor of the Company. All
payments to be made hereunder shall be paid from the general funds of the
Company and no special or separate fund shall be established and no segregation
of assets shall be made to assure payment of any amount hereunder.

                  (c)      This Agreement shall be governed by and construed and
enforced in accordance with the laws of the State of New York, without giving
effect to the principles of conflicts of laws of that State.

                  (d)      This Agreement shall be binding upon and inure to the
benefit of the Company, its successors and assigns, and the Employee, his heirs,
devisees, distributees and legal representatives.

                  (e)      Any notice or other communication to the Company
pursuant to any provision of this Agreement shall be given in writing and will
be deemed to have been delivered:

                                       16

<PAGE>

                           (i)      when delivered in person to the Corporate
Secretary or Chief Executive Officer of the Company; or

                           (ii)     one week after it is deposited in the United
States certified or registered mail, postage prepaid, addressed to the Corporate
Secretary of the Company at 300 Corporate Drive, Building #10, Bradley Corporate
Park, Blauvelt, New York 10913 or at such other address of which the Company may
from time to time give the Employee written notice in accordance with paragraph
13(f) below.

                  (f)      Any notice or other communication to the Employee
pursuant to any provision of the Agreement shall be given in writing and will be
deemed to have been delivered:

                           (i)      when delivered to the Employee in person, or

                           (ii)     one week after it is deposited in the United
States certified or registered mail, postage prepaid, addressed to the Employee
at his address as it appears on the records of the Company or at such other
address of which the Employee may from time to time give the Company written
notice in accordance with paragraph 13(e) above.

                  (g)      No provision of this Agreement may be amended,
modified or waived unless such amendment, modification or waiver shall be agreed
to in a writing signed by the Employee and an authorized officer of the Company.

                  (h)      This instrument contains the entire agreement of the
parties relating to the subject matter of this Agreement and supersedes and
replaces all prior agreements and understandings with respect to such subject
matter, and the parties have made no agreements, representations or warranties
relating to the subject matter of this Agreement which are not set forth herein.

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the date first above written.

                                                    BARR LABORATORIES, INC.

                                                    By: /s/ Catherine F. Higgins
                                                       -------------------------
[SEAL]
Attest:

/s/ Phillandas Thompson                                 /s/ Salah U. Ahmed
-----------------------                                -------------------------
Secretary                                              Employee

                                       17

<PAGE>

                                                                        APPENDIX

 EXAMPLES ILLUSTRATING INTENDED OPERATION OF EXTENSION PROVISIONS OF PARAGRAPH 2

Example 1:

                  Facts: Neither the Company nor the Employee gives the other
                  party written notice of non-extension before the date that is
                  six months before the third anniversary of the Commencement
                  Date.

                  Result: Effective as of the date that is six months before the
                  third anniversary of the Commencement Date, the term of the
                  Agreement is extended 12 months, so that it will expire on the
                  fourth anniversary of the Commencement Date unless further
                  extended in accordance with the provisions of Paragraph 2 of
                  the Agreement.

Example 2:

                  Facts: Either the Company or the Employee gives the other
                  party written notice of non-extension before the date that is
                  six months before the third anniversary of the Commencement
                  Date.

                  Result: The term of the Agreement is not extended, and expires
                  on the third anniversary of the Commencement Date.

Example 3:

                  Facts: Neither the Company nor the Employee gives the other
                  party written notice of non-extension before the date that is
                  six months before the fourth anniversary of the Commencement
                  Date.

                  Result: Effective as of the date that is six months before the
                  fourth anniversary of the Commencement Date, the term of the
                  Agreement as extended in accordance with Example 1 above is
                  further extended 12 months, so that it will expire on the
                  fifth anniversary of the Commencement Date unless further
                  extended in accordance with the provisions of Paragraph 2 of
                  the Agreement.

Example 4:

                  Facts: Either the Company or the Employee gives the other
                  party written notice of non-extension on or after the date
                  that is six months before the fourth anniversary of the
                  Commencement Date and before the date that is six months
                  before the fifth anniversary of the Commencement Date.

                  Result: The term of the Agreement as extended is not further
                  extended, and expires on the fifth anniversary of the
                  Commencement Date.

                                       18