EXHIBIT 10.43(a)















                             MANUGISTICS GROUP, INC.

                             STOCK OPTION AGREEMENT


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                             STOCK OPTION AGREEMENT

     This Stock Option  Agreement,  dated as of April 27, 1999 is by and between
Manugistics Group, Inc., a Delaware corporation (the "Company"), and Greg Owens,
an  individual  residing  at 315  Rainwater  Road,  Senoia,  Georgia  30276 (the
"Employee").

                                   BACKGROUND

     Employee  was  employed by the Company as its Chief  Executive  Officer and
President pursuant to the terms of that certain letter agreement dated April 25,
1999 between  Employee and the Company (the  "Employment  Letter").  In order to
provide the Employee with a direct proprietary interest in the future success of
the Company and to encourage the Employee to achieve  maximum  performance  with
the Company,  the Company agreed as provided in the Employment  Letter, to grant
to the  Employee an option to purchase  2,000,000  shares of Common Stock of the
Company at a price of Seven and thirteen-sixteenths Dollars ($7.8125) per share,
on the terms and subject to the conditions set forth herein.

     NOW,  THEREFORE,  in view of the  foregoing,  and in  consideration  of the
promises herein  contained,  and each intending to be legally bound hereby,  the
parties agree as follows:

     1.   Grant of Option; Payment of Exercise Price.

     a. The  Company  hereby  grants to the  Employee  the  right and  option to
purchase under the terms and conditions set forth below, 2,000,000 shares of the
Company's   common   stock,   (the   "Shares"),   at  a  price  of   Seven   and
thirteen-sixteenths  Dollars  ($7.8125) per share (the "Purchase Price") payable
as set forth below (the "Option").

     b. The Option may be exercised, in whole or in part as to a minimum of 50


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shares or if fewer, the total number of shares subject to the Option,  by giving
written notice of exercise to the Company  specifying the number of Shares to be
purchased.  Such notice shall be  accompanied by payment in full of the purchase
price, plus any required federal, state and/or local withholding taxes, in cash,
or in shares of common stock of the Company  already  owned by the Employee with
such shares valued at their Fair Market Value.  For such purposes,  "Fair Market
Value" shall be defined as the closing  price of the common stock of the Company
on the day  immediately  preceding  the exercise  date as reported on the Nasdaq
System.  The  Employee  may also  simultaneously  exercise the Option (or a part
thereof)  and sell all or part of the Shares  thereby  acquired  pursuant to any
arrangement  then in effect  between any broker and the Company,  and to use the
proceeds from such sale to pay the exercise price and withholding taxes.

     2. Terms and Exercise of Option.

     a. The  Option  shall have a term of ten years  from the date  hereof,  and
shall  vest in sixty  equal  monthly  installments  over the  five  year  period
beginning  on the date hereof  (the  "Vesting  Period").  The Option may only be
exercised during the ten year term hereof and only to the extent it is vested.

     b. In the event of a Change in Control of the Company (defined below),  (i)
if the Employee's  responsibilities are not affected, fifty percent (50%) of the
outstanding   Option  shall   immediately  vest,  and  (ii)  if  the  Employee's
responsibilities are significantly  diminished or the Employee is constructively
terminated  (i.e.,  the Employee's  responsibilities  no longer consist of those
reasonably   associated  with  the  position  of  Chief  Executive  Officer  and
President)  one  hundred  percent  (100%)  of  the   outstanding   Option  shall
immediately vest, in each instance as of

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the  effective  date of such  Change in Control,  without  regard to the Vesting
Period.  A Change in Control  shall be deemed to have  occurred  at such time as
fifty one percent (51%) of the  Company's  voting stock shall have been acquired
by any  person  and/or its  affiliates  in a single  transaction  or a series of
related transactions.

     c. In the event the  Employee's  employment  with the Company is terminated
without cause by the Company, vesting of the Option shall accelerate for the six
monthly  installments   immediately   following  such  date  of  termination  of
employment,  and any  remaining  portion  of the  Option  which is not vested or
accelerated as of such date of termination, shall terminate.

     d. In the event the Employee's employment with the Company is terminated by
the Company for cause or voluntarily by the Employee,  any portion of the Option
not vested as of such date of termination  of employment  shall  terminate.  For
purposes hereof, "cause" shall mean (i) substantial and continued failure by the
Employee to perform his duties as President  and Chief  Executive  Officer which
results,  or could  reasonably  be expected to result,  in material  harm to the
business or reputation  of the Company,  which failure is not cured (if curable)
by the Employee within fifteen (15) days after written notice of such failure is
delivered  to the  Employee by the  Company,  (ii) gross  misconduct  including,
without  limitation,  embezzlement,  fraud,  or  misappropriation,  or (iii) the
commission of a felony.

     e. In no event may this Option be exercised after the expiration of the ten
year term hereof.  Except as provided in this Paragraph 2(e), no portion of this
Option may be  exercised  unless the  Employee is employed by the Company at the
time of exercise, and may only be

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exercised by the following persons,  under the following conditions,  and in all
cases subject to all  provisions of this Option  Agreement,  and all  applicable
laws,  rules  and  regulations:  (i) by the  Employee,  (ii)  by the  Employee's
permitted transferees as provided below in Paragraph 2(f), (iii) if the Employee
shall become disabled or die, and shall not have fully exercised the Option,  by
the  Employee or by the  executors or  administrators  of the Employee or by any
person or persons who shall have acquired the Option  directly from the Employee
by  bequest  or  inheritance,  but only  within one year of the date of death or
disability,  (iv) by the  Employee in the event that the  Employee's  employment
with the Company is  terminated  without  cause by the Company,  but only within
three  months  after  such  date of  termination  of  employment;  or (v) by the
Employee  in the  event  that the  Employee's  employment  with the  Company  is
terminated  voluntarily  by the Employee or with cause by the Company,  but only
within one month after such date of termination  of employment.  Notwithstanding
the foregoing, the Option may be exercised only to the extent that the Option is
vested pursuant to Paragraphs  2(a), 2(b), 2(c) or 2(d) of this Agreement at the
date of the Employee's disability, death or termination of employment.

     f.  Except as  provided  herein,  no part of this  Option,  and no right or
interest  therein,  shall be (i)  assignable,  alienable or  transferable by the
Employee,  except  by will or the  laws of  descent  and  distribution,  or (ii)
subject  to any  obligation,  or the  lien or  claims  of any  creditor,  of the
Employee,  or (iii) subject to any lien,  encumbrance or claim of any party made
in respect of or through the Employee,  however arising.  During the lifetime of
the Employee, this Option is exercisable only by, and the Shares issued upon the
exercise  of this  Option will be issued  only to the  Employee,  his  permitted
transferees, or his legal representative. Notwithstanding the

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foregoing,  the Employee may transfer all or a portion of this Option; provided,
that in no event shall any transfer be made to any person or persons  other than
the Employee's parents, spouse or other life partner, children or grandchildren,
siblings,  or children of siblings,  or a trust for the exclusive benefit of one
or more such  persons,  which  transfer  must be made as a gift and  without any
consideration,  or pursuant to a qualified  domestic  relations order. All other
transfers and any retransfer by any permitted  transferee are prohibited and any
such  purported  transfer  shall be null and void.  This Option and the Employee
shall  continue to be subject to the same terms and conditions as were in effect
immediately  prior  to  such  permitted  transfer.  The  Employee  shall  remain
responsible to the Company for the payment of all withholding  taxes incurred as
a result  of any  exercise  of this  Option.  In no event  shall  any  permitted
transfer of this Option create any right in any party in respect of this Option,
other than the right of the permitted  transferee to exercise this Option to the
extent the  Employee  could have  exercised  this Option had such  transfer  not
occurred.

     3. Recapitalization; Anti-Dilution Protection.

     a. Subject to any required action by the  stockholders of the Company,  the
number of Shares which may be  purchased  at any time under the Option,  and the
price per share therefor,  shall be proportionately adjusted for any increase or
decrease in the number of outstanding  shares of the common stock of the Company
resulting  from a  subdivision  or  consolidation  of shares or the payment of a
stock  dividend (but only on the common stock) or any other increase or decrease
in the number of such shares effected  without receipt of  consideration  by the
Company,  such that,  upon exercise of the Option from time to time  thereafter,
the

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Employee  shall be  entitled  to receive  such number of Shares as he would have
received had the Option been exercised prior to such action.

     b. If the Board of Directors of the Company, during the twelve month period
beginning  on the date  hereof,  directs  management  of the  Company  to obtain
additional  equity  capital (other than through the Company's  employee  benefit
plans),  the Company will provide to the Employee  (provided Employee is then an
employee of the Company)  anti-dilution  protection for this Option with respect
to  common  stock  or   Convertible   Securities   (defined   below)  issued  in
consideration  for the  first  Fifteen  Million  Dollars  ($15,000,000)  of such
additional equity capital obtained. The anti-dilution protection shall be in the
form of  additional  options  granted to Employee  upon the closing  date of the
investment  of such  additional  equity  capital,  (i) priced at the Fair Market
Value of the common stock of the Company on the day  immediately  preceding such
closing  date,  (ii)  subject to terms and  conditions  similar to the terms and
conditions  of this  Option  and (iii)  equal to the  number of shares of common
stock  necessary,  which when added to the Option for  2,000,000  shares  issued
hereunder,  to cause the percentage of  outstanding  common stock of the Company
represented by the sum of the Option and such additional options, to be equal to
the percentage that the Option represented on the date of this Option Agreement,
adjusted  for any  other  issuances  of common  stock  for  which  anti-dilution
protection is not granted hereunder. Vesting of such additional options shall be
in accordance  with the original  grant of this Option  (i.e.,  monthly over the
remaining  Vesting Period).  In the event the securities issued in consideration
for the additional equity capital are in the form of securities convertible into
common  stock  ("Convertible  Securities"),  the  number of  additional  options
granted hereunder shall be determined

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as if the  conversion  rights  attached  to  such  Convertible  Securities  were
immediately exercised; however, the additional options issued as a result of the
issuance of the Convertible Securities shall only be exercisable pro rata to the
extent and at such time as the conversion  rights  attached to such  Convertible
Securities are actually  exercised.  The condition to exercise  contained in the
immediately  preceding  sentence  hereof  shall be applied in  addition  to, and
separately  from, the requirement that the options must be vested in order to be
exercisable.

     4. Consolidation; Merger; Dissolution and Conversion.

     a. Subject to any required action by the  shareholders  of the Company,  if
the Company shall be the surviving  corporation in any merger or  consolidation,
while any part of this Option remains unexercised, such unexercised part of this
Option  shall  pertain to and apply to the  securities  to which a holder of the
number of Shares  subject  hereto would have been entitled  (i.e.,  the Employee
shall be  entitled  to  purchase  such  number of  securities  as he would  have
received had this Option been exercised prior to such merger or consolidation).

     b. Subject to ss.2(b)  above,  in the event of a dissolution or liquidation
of the  Company  or a merger or  consolidation  in which the  Company is not the
surviving  corporation,  the  Employee  shall,  in such  event,  have the right,
immediately prior to such dissolution,  liquidation, merger or consolidation, to
exercise  this  Option in whole or in part  without  regard  to the  installment
provisions  of  Paragraph  2(a)  above,  unless  this  Option is  assumed by the
surviving or acquiring corporation, or its parent.

     c. In the event of a change in the Common Stock of the Company as presently
constituted,  which is limited to a change of all of its authorized  shares with
par value into the same

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number of shares  with a different  par value or without  par value,  the shares
resulting  from any such change shall be deemed to be Shares  within the meaning
of this Option.

     5. Notice of Exercise.  The Option shall be  exercisable  upon the Employee
giving (a) written notice to the Company of such exercise  specifying the number
of Shares to be purchased, (b) payment of the Purchase Price of the Shares being
purchased and any  applicable  withholding  taxes as provided in Paragraph  1(b)
above,  and,  subject to applicable  federal and state securities laws, shall be
effective upon actual receipt of the foregoing (a) and (b).

     6. Failure to Exercise.  If the Employee  fails to exercise any part of the
Option in  accordance  with the terms of this  Agreement  within  the period set
forth in Paragraph 2(a) above,  then such part and all rights  attached  thereto
shall  automatically and immediately  terminate  without notice.  This Agreement
does not impose any  obligation  on the  Employee to exercise  the Option or any
part  hereof nor does it modify the other  terms of  Employee's  employment  set
forth  in the  Employment  Letter.  The  Employee  shall  have  no  rights  as a
stockholder  of the  Company  with  respect to the Shares  covered by the Option
unless  and  except to the  extent  that the  Option  shall  have  been  validly
exercised.

     7. Notices. Any and all notices or other writings, which are required to be
served, or which may be served under the provisions of this Agreement,  shall be
in writing,  and shall be sufficiently served if delivered  personally or mailed
by registered or certified mail (return receipt requested),  postage prepaid, to
the parties at the addresses set forth on the first page of this  Agreement,  or
at such  other  address  for a party  as  shall  be  specified  by like  notice;
provided,  that  notices of a change of  address  shall be  effective  only upon
receipt thereof. If mailed as aforesaid,

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three  (3) days  after the date of  mailing  shall be the date  notice  shall be
deemed to have been received.

     8. Entire  Agreement.  This Agreement and the Employment  Letter constitute
the entire agreement between the parties hereto pertaining to the subject matter
hereof, and supersede all prior and contemporaneous  agreements,  understandings
and discussions,  whether written or oral between the parties and may be amended
only by a written document signed by the parties hereto.

     9. Governing Law. This Agreement  shall be governed by and construed  under
the laws of the State of Delaware,  without reference to principles of conflicts
of laws.

     10.  Headings.   The  headings  and  captions   contained  herein  are  for
convenience  only and shall not control or affect the meaning or construction of
any provision hereof.

     11.  Corporate  Action.  No  provision of this Option shall be construed to
prevent the Company from taking any corporate action deemed by the Company to be
appropriate  or in its best  interest,  whether or not such action could have an
adverse  effect on this  Option,  and  neither the  Employee  or the  Employee's
estate, personal representative,  beneficiary or permitted transferee shall have
any claim against the Company as a result of taking such action.

     IN WITNESS WHEREOF, the patties hereto have executed this Option on the day
and year first above written. MANUGISTICS GROUP, INC.

By: /s/ Helen A. Nastasia
   -------------------------------------
Title: V.P., General Counsel & Secretary
      ----------------------------------
EMPLOYEE:
/s/ Gregory J. Owens
---------------------------
Greg Owens

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