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                                                                  EXHIBIT 10.125


                                     FORM OF
                            INDEMNIFICATION AGREEMENT
                           FOR DIRECTORS AND OFFICERS


                  THIS INDEMNIFICATION AGREEMENT ("Agreement") is made as of
this ____ day of December, 1996, between Ecogen Inc., a Delaware corporation
(the "Company"), and ("Officer" ["Director"]).

                                WITNESSETH THAT:

                  WHEREAS, Officer [Director] is an executive officer [a member
of the Board of Directors] of the Company and in such capacity is performing a
valuable service for the Company; and

                  WHEREAS, the by-laws of the Company (the "By-laws") provide
for the indemnification of its directors and executive officers to the maximum
extent authorized by law; and

                  WHEREAS, Section 145 of the Delaware General Corporation Law
(the "DGCL") specifically provides that it shall not be deemed exclusive of any
other rights to indemnification or advancement of expenses to which directors or
officers may be entitled under any by-law, agreement, vote of stockholders or
disinterested directors or otherwise; and

                  WHEREAS, the number of lawsuits and shareholders' derivative
lawsuits against corporations, their directors and officers has increased in
recent years, such lawsuits frequently are without merit and seek damages in
amounts having no reasonable relationship to the amount of compensation received
by the directors and officers from the corporation, and such lawsuits whether or
not meritorious are expensive and time-consuming to defend; and

                  WHEREAS, recent developments with respect to the application
and interpretation of the business judgment rule and statutory and by-law
indemnification provisions have created uncertainty regarding the adequacy and
reliability of the protections afforded to directors and officers thereby; and

                  WHEREAS, adequate directors and officers liability insurance
may not be available at a reasonable cost; and


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                  WHEREAS, the Company wishes to have Officer [Director]
continue to serve as an executive officer [a director] of the Company free from
undue concern for unpredictable or unreasonable claims for damages by reason of
Officer's [Director's] status as an executive officer [a director] of the
Company, by reason of Officer's [Director's] decisions or actions on its behalf
or by reason of Officer's [Director's] decisions or actions in another capacity
while serving as an executive officer [a director] of the Company; and

                  WHEREAS, Officer [Director] has expressed reluctance to
continue to serve as an executive officer [a director] of the Company without
assurances that adequate insurance and indemnification is and will continue to
be provided; and

                  WHEREAS, in order to induce Officer [Director] to continue to
serve as an executive officer [a director] of the Company, the Company has
determined and agreed to enter into this Agreement with Officer [Director];

                  NOW, THEREFORE, in consideration of Officer's [Director's]
continued service as an executive officer [a director] of the Company, the
parties agree as follows:

                  1.       Directors and Officers Liability Insurance.

                           (a)  Except as provided in (b) below, the Company 
hereby agrees to use its best efforts to obtain and maintain directors and
officers liability insurance for Officer [Director] for so long as Officer
[Director] shall continue to serve as an executive officer [a director] of the
Company and thereafter so long as Officer [Director] shall be subject to any
possible claim or threatened, pending or completed action, suit or proceeding,
whether civil, criminal, administrative or investigative, by reason of the fact
that Officer [Director] was an executive officer [a director] of the Company.

                           (b)  The Company shall have no obligation hereunder
to obtain or maintain directors and officers liability insurance if, in the
reasonable business judgment of the Board of Directors of the Company, such
insurance is not reasonably available, the premium costs for such insurance are
disproportionate to the amount of coverage provided, or the coverage provided by
such insurance is limited, by exclusions or otherwise, so as to provide an
insufficient benefit.


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                           (c)  In all policies of directors and officers 
liability insurance, Officer [Director] shall be covered as an insured party in
such a manner as to provide Officer [Director] the same rights and benefits,
subject to the same limitations, as are accorded to the Company's executive
officer [director] most favorably insured by such policies.

                           (d)  The Company shall give prompt written notice to
Officer [Director] of any amendment or other change or modification, or any
proposed amendment, change or modification, to any policy of directors and
officers liability insurance maintained by the Company and covering Officer
[Director].

                  2.       Indemnification of Officer [Director]. Subject only
to the exclusions set forth in this Agreement, the Company hereby agrees to hold
harmless and indemnify Officer [Director] to the full extent authorized or
permitted by Section 145 of the DGCL, including any amendment thereof, or any
other statutory provisions authorizing or permitting such indemnification which
are adopted after the date hereof. Notwithstanding the foregoing, the Company
shall not be required to indemnify Officer [Director] for any losses to the
extent that such losses are covered by directors and officers liability
insurance as described in Section 1 above. Without limiting the generality of
the foregoing:

                           (a)  Third Party Actions.  The Company shall 
indemnify Officer [Director] if Officer [Director] was or is a party or is
threatened to be made a party to any action, suit or proceeding, whether civil,
criminal, administrative or investigative (other than an action by or in the
right of the Company) by reason of the fact that Officer [Director] is or was or
had agreed to serve as (so long as Officer [Director] actually is serving or did
so serve) an executive officer [a director] of the Company, or is or was serving
or had agreed to serve as an executive officer [a director] (so long as Officer
[Director] actually is serving or did so serve) at the request of the Company as
a director, officer, employee or agent of another corporation, limited liability
company, partnership, joint venture, trust or other enterprise, against any and
all expenses (including attorneys' fees), liabilities, judgments, penalties,
fines and amounts paid in settlement actually and reasonably incurred by Officer
[Director] or on Officer's [Director's] behalf in connection with such action,
suit or proceeding, and any appeal therefrom, if Officer [Director] acted in
good faith and in a manner Officer [Director] reasonably believed to be in or
not opposed to the best interests of the Company, and, with respect to any
criminal action or proceeding, had no reasonable cause to believe Officer's
[Director's] conduct was unlawful. The termination of any action, suit or
proceeding by judgment, order, settlement, conviction or upon a plea of nolo
contendere or its equivalent shall not, of itself, create a presumption that
Officer [Director] did not satisfy the foregoing standard of conduct to the
extent applicable thereto.


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                           (b)  Suits By or in the Right of the Company.  The 
Company shall indemnify Officer [Director] if Officer [Director] is or was a
party or is threatened to be made a party to any action or suit by or in the
right of the Company by reason of the fact that Officer [Director] is or was or
had agreed to be (so long as Officer [Director] actually is or did become) an
executive officer [a director] of the Company, or is or was serving or had
agreed to serve (so long as Officer [Director] actually is or did so serve) at
the request of the Company as a director, officer, employee or agent of another
corporation, limited liability company, partnership, joint venture, trust or
other enterprise, against any and all expenses (including attorneys' fees) and,
to the extent permitted by law, amounts paid in settlement actually and
reasonably incurred by Officer [Director] or on Officer's [Director's] behalf in
connection with the defense or settlement of such action or suit or any appeal
therefrom provided that Officer [Director] acted in good faith and in a manner
Officer [Director] reasonably believed to be in or not opposed to the best
interests of the Company and except that no indemnification shall be made in
respect of any claim, issue or matter as to which Officer [Director] shall have
been adjudged to be liable to the Company unless and only to the extent that the
court in which such action or suit was brought shall determine upon application
that, despite the adjudication of liability but in view of all the circumstances
of the case, Officer [Director] is fairly and reasonably entitled to indemnity
for such expenses which the court shall deem proper.

                           (c)  Successful Defense.  To the extent that Officer
[Director] has been successful on the merits or otherwise in the defense of any
action, suit or proceeding referred to in subsections (a) or (b) of this Section
2, or in the defense of any claim, issue or matter therein, the Company shall
indemnify Officer [Director] against any and all expenses (including attorneys'
fees) actually and reasonably incurred by Officer [Director] or on Officer's
[Director's] behalf in connection therewith. Dismissal of any action with
prejudice, or a settlement not involving any payment or assumption of liability,
shall be deemed a successful defense.

                           (d)  Partial Indemnification.  If Officer [Director]
is entitled to indemnification under any provision of this Agreement for a
portion of the expenses (including attorneys' fees), liabilities, judgments,
penalties, fines and amounts paid in settlement actually and reasonably incurred
by Officer [Director] or on Officer's [Director's] behalf in the investigation,
defense, appeal or settlement of such suit, action or proceeding, but not,
however, for the total amount thereof, the Company shall nevertheless indemnify
Officer [Director] for the portion thereof to which Officer [Director] is
entitled.

                           (e)  Advancement of Expenses.  All expenses 
(including attorney and other expert and professional fees and expenses)
incurred by Officer [Director] or on Officer's [Director's] behalf in defending
a civil or criminal action, suit


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or proceeding, or in enforcing Officer's [Director's] rights under any
provisions of this Agreement, shall be paid by the Company in advance of the
final disposition of such action, suit or proceeding in the manner prescribed by
Section 4 hereof.

                           (f)  Amendments to Indemnification Rights.  The 
Company shall not adopt any amendment to its Certificate of Incorporation, as
amended (the "Certificate") or By-Laws the effect of which would be to deny,
diminish or encumber Officer's [Director's] rights to indemnity pursuant to the
Certificate, By-Laws, the DGCL or any other applicable law as applied to any act
or failure to act occurring in whole or in part prior to the date (the
"Effective Date") upon which the amendment was approved by the Company's Board
of Directors or stockholders, as the case may be. In the event that the Company
shall adopt any amendment to the Certificate or By-Laws the effect of which is
to change Officer's [Director's] rights to indemnity under such instruments,
such amendment shall apply only to acts or failures to act occurring entirely
after the Effective Date thereof. The Company shall give written notice to
Officer [Director] of any proposal with respect to any such amendment no later
than the date such amendment is first presented to the Board of Directors (or
any committee thereof) for consideration, and shall provide a copy of any such
amendment to Officer [Director] promptly after its adoption.

                           (g)  indemnification for Expenses as a Witness.  To
the extent Officer [Director] is, by reason of Officer's [Director's] status as
an executive officer [a director] of the Company, a witness in any proceeding,
the Company shall indemnify Officer [Director] against all expenses in
connection therewith.

                  3.       Limitations on Indemnification.  No indemnity 
pursuant to Section 2 hereof shall be paid by the Company:

                           (a)  on account of Officer's [Director's] conduct 
which is finally adjudged in a non-appealable decision to have been fraudulent,
dishonest or willful misconduct, or a knowing violation of law;

                           (b)  on account of any suit in which judgment in a 
final, non-appealable decision is rendered against Officer [Director] for an
accounting of profits made from the purchase or sale by Officer [Director] of
securities of the Company within the meaning of Section 16(b) of the Securities
Exchange Act of 1934, as amended, or similar provisions of federal or state law;

                           (c)  on account of the receipt by Officer [Director]
of any personal profit or advantage to which Officer [Director] is adjudged in a
final, non-appealable decision not to be entitled;

                           (d)  for expenses incurred by Officer [Director], as
a plaintiff, in suits against the Company or against other executive officers
[directors] of the Company (other than suits


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brought by Officer [Director] to enforce Officer's [Director's] rights under any
provisions of this Agreement), unless such suit is authorized by the Board of
Directors or such indemnification is required by law;

                           (e)  if a final, non-appealable decision by a court
having jurisdiction in the matter shall determine that such indemnification is
not lawful; or

                           (f)  for amounts paid by Officer [Director] in
settlement of any action or proceeding without the Company's written consent.

                  4.       Indemnification Procedures.

                           (a)  Notice to the Company.  Promptly after receipt
by Officer [Director] of notice of the commencement of any action, suit or
proceeding, Officer [Director] shall, if a claim in respect thereof is to be
made against the Company under this Agreement, notify the Company of the
commencement thereof. Such notice shall set forth in reasonable detail the
events giving rise to such claim and the amount requested, if known. Failure of
Officer [Director] to provide such notice shall not relieve the Company of its
obligations under this Agreement except to the extent such failure has a
material and adverse effect on the ability of the Company to meet such
obligations.

                           (b)  Notice to Insurers.  If, at the time of receipt 
of such notice, the Company has directors and officers liability insurance in
effect, the Company shall give prompt notice of the commencement of such action,
suit or proceeding to the insurers in accordance with the procedures set forth
in the respective policies in favor of Officer [Director]. The Company shall
thereafter take all necessary or desirable action to cause such insurers to pay,
on behalf of Officer [Director], all losses and expenses payable as a result of
such action, suit or proceeding in accordance with the terms of such policies.

                           (c)  Advancement of Expenses.  Subject to subsections
(d) and (e) below, the costs and expenses reasonably incurred by Officer
[Director] or on Officer's [Director's] behalf in investigating, defending or
appealing any action, suit or proceeding, whether civil, criminal,
administrative or investigative, or in enforcing Officer's [Director's] rights
under any provisions of this Agreement, covered by Section 2 above shall be paid
by the Company within 20 days of Officer's [Director's] written request therefor
even if there has been no final disposition of such action, suit or proceeding.
Officer's [Director's] written request shall state the amount requested and
shall be accompanied by copies of the invoices or other relevant documentation.

                           (d)  Undertaking to Repay Advances.  Officer 
[Director] agrees that Officer [Director] will reimburse the Company for all
advances paid by the Company to Officer


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[Director] under this Agreement in the event and only to the extent that it
shall ultimately be determined that Officer [Director] was not entitled to be
indemnified under this Agreement.

                           (e)  Assumption of Defense by the Company.  Except as
otherwise provided below, the Company, jointly with any other indemnifying party
similarly notified, will be entitled to assume the defense of any action, suit
or proceeding of which it has been notified by Officer [Director] pursuant to
subsection (a) above, with counsel reasonably satisfactory to Officer
[Director]. After notice from the Company to Officer [Director] of its election
to assume the defense thereof, the Company will not be liable to Officer
[Director] under this Agreement for any legal or other expenses subsequently
incurred by Officer [Director]; provided, however, that Officer [Director] shall
have the right to employ Officer's [Director's] own counsel in such action, suit
or proceeding at the expense of the Company if, at any time after such notice
from the Company, (i) the employment of counsel by Officer [Director] has been
authorized by the Company, (ii) Officer [Director] shall have reasonably
concluded that there may be a conflict of interest between the Company and
Officer [Director] in the conduct of such defense, or (iii) the Company shall
not in fact have employed counsel to assume the defense of such action, in each
of which cases the fees and expenses of Officer's [Director's] counsel shall be
subject to reimbursement in accordance with the terms of this Agreement. The
Company shall not be entitled to assume Officer's [Director's] defense of any
action, suit or proceeding brought by the Company or as to which Officer
[Director] shall have made the conclusion provided for in clause (ii) above.

                           (f)  Determination of Right to Entitlement.  (i)  In
the event that Officer [Director] incurs liability for any fines, judgments,
liabilities, penalties or amounts paid in settlement, and indemnification is
sought under this Agreement, the Company shall pay (or provide for payment if so
required by the terms of any judgment or settlement) such amounts within 30
business days of Officer's [Director's] written request therefor unless a
determination is made within such 30 business days that the claims giving rise
to such request are excluded or indemnification is otherwise not due under this
Agreement. Such determination, and any determination required by applicable law
as to whether Officer [Director] has met the standard of conduct required to
qualify and entitle Officer [Director], partially or fully, to indemnification
under Section 2 of this Agreement, shall be made, at the Company's discretion,
(1) by the Board of Directors of the Company by a majority vote of the directors
who were not parties to such action, suit or proceeding even though less than a
quorum, or (2) if such a majority is not obtainable, or even if obtainable a
majority of the disinterested directors so directs, by written opinion of
independent legal counsel selected by the Company and reasonably satisfactory to
Officer [Director], or (3) by the Company's stockholders; provided, however,
that if a change of control has occurred such 


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determination shall be made by written opinion of independent legal counsel
selected by Officer [Director] or, if requested by Officer [Director], by the
Company. The term "independent legal counsel" shall mean for this purpose an
attorney or firm of attorneys experienced in matters of corporation law that is
not now nor has within the previous three years been retained to represent
Officer [Director], the Company or any other party to the proceeding giving rise
to the claim for indemnification hereunder; provided that "independent legal
counsel" shall not include any person who under applicable standards of
professional conduct would have a conflict of interest in representing Officer
[Director] or the Company in an action to determine Officer's [Director's]
rights under this Agreement. The term "change of control" shall mean: (1) the
consummation of any transaction after which any "person" or "group" (as such
terms are used in Sections 3(a)(9), 13(d)(3) or 14(d)(2) of the Securities
Exchange Act of 1934 (the "Exchange Act")) is or becomes the "beneficial owner"
(as defined in Rule 13d-3 under the Exchange Act), directly or indirectly, of
securities, or possesses the power to vote or control the vote of securities, of
the Company representing 30% or more of the combined voting power of either the
Common Stock or all outstanding securities of the Company; or (2) the
stockholders of the Company approve a merger or consolidation of the Company
with any other corporation or entity, other than a merger or consolidation which
would result in the voting securities of the Company outstanding immediately
prior thereto continuing to represent (either by remaining outstanding or by
being converted into voting securities of the surviving entity) at least 66 2/3%
of the combined voting power of the voting securities of the Company or such
surviving entity outstanding immediately after such merger or consolidation, or
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.

                 (ii) Notwithstanding the foregoing, Officer [Director] may
within 60 days after a determination adverse to Officer [Director] has been made
as provided above, or if no determination has been made within 30 business days
of Officer's [Director's] written request for payment, petition the Court of
Chancery of the State of Delaware or any other court of competent jurisdiction,
or may seek an award in arbitration to be conducted by a single arbitrator
pursuant to the rules of the American Arbitration Association, which award shall
be deemed final, unappealable and binding, to determine whether Officer
[Director] is entitled to indemnification under this Agreement, and such court
or arbitrator, as the case may be, shall thereupon have the exclusive authority
to make such determination unless and until such court or arbitrator dismisses
or otherwise terminates such action without having made a determination. The
court or arbitrator, as the case may be, shall make an independent determination
of entitlement irrespective of any prior determination made by the Board of
Directors, independent legal counsel or stockholders. In any such action before
the court or 


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arbitrator, Officer [Director] shall be presumed to be entitled to
indemnification and the Company shall have the burden of proving that
indemnification is not required under this Agreement. All fees and expenses of
any arbitrator pursuant to this provision shall be paid by the Company.

                     (g)  Enforcement Expenses.  In the event that Officer 
[Director] brings suit or takes any other action to enforce Officer's
[Director's] rights or to collect monies due under this Agreement, and if
Officer [Director] is successful therein, the Company shall reimburse (to the
extent not previously advanced) Officer [Director] for all of Officer's
[Director's] reasonable expenses, including attorneys' fees, in any such suit or
action.

                  5. Continuation of Indemnification. The Company's obligations
to indemnify Officer [Director] hereunder shall continue throughout the period
Officer [Director] is an executive officer [a director] of the Company (or is
serving at the Company's request in the capacities described in subsections 2(a)
and 2(b) above) and thereafter so long as Officer [Director] shall be subject to
any possible claim, action, suit or proceeding by reason of the fact that
Officer [Director] was an executive officer [a director] of the Company (or was
serving in such other capacities).

                  6. Successors and Assigns. This Agreement shall be binding
upon the Company, its successors and assigns (including any transferee of all or
substantially all of its assets and any successor by merger or otherwise by
operation of law), and shall inure to the benefit of Officer [Director] and
Officer's [Director's] heirs, personal representatives, executors and
administrators and shall be binding upon Officer [Director] and Officer's
[Director's] successors in interest under this Agreement.

                  7. Rights Not Exclusive. The rights provided hereunder shall
not be deemed exclusive of any other rights to which Officer [Director] may be
entitled under any provision of law, By-law, other agreement, vote of
stockholders or of disinterested directors or otherwise, both as to action in
Officer's [Director's] official capacity and as to action in any other capacity
while occupying any of the positions referred to in Section 2 of this Agreement.

                  8. Subrogation. Upon payment of any amount under this
Agreement, the Company shall be subrogated to the extent of such payment to all
of Officer's [Director's] rights of recovery therefor and Officer [Director]
shall take all reasonable actions requested by the Company to secure such
rights, including, without limitation, execution of all documents necessary to
enable the Company to enforce such rights.


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                  9.  Severability. In the event that any provision of this
Agreement shall be held to be invalid, illegal or unenforceable for any reason,
such provision shall be limited or modified in its application to the minimum
extent necessary to avoid a violation of law, and, as so limited or modified,
such provision and the balance of this Agreement shall be enforceable in
accordance with their terms.

                  10. Integration.  This Agreement embodies the entire agreement
and understanding between the parties hereto with respect to the subject matter
hereof and supersedes all prior agreements and understandings relating to the
subject matter hereof.

                  11. Modification.  No amendment, modification, termination or
cancellation of this Agreement shall be effective unless in writing signed by
both parties hereto.

                  12. Notices. All notices given under this Agreement shall be
in writing and delivered either (i) personally, (ii) by registered or certified
mail (postage prepaid, return receipt requested), (iii) by recognized overnight
courier service or (iv) by telecopy (if promptly followed by a copy delivered as
provided in clauses (i), (ii) or (iii) above), as follows:

         If to Officer [Director]:_______________________________________

                                  _______________________________________

                                  _______________________________________


         If to the Company:   Ecogen Inc.
                              2005 Cabot Boulevard West
                              Langhorne, Pennsylvania  19047

Notices hereunder given as provided above shall be deemed to be duly given upon
delivery if delivered personally, three business days after mailing if by
registered or certified mail, one business day after mailing if by overnight
courier service and upon confirmation of transmission if by telecopy.

                  13. Governing Law.  This Agreement shall be interpreted and 
enforced in accordance with the laws of the State of Delaware.


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                  IN WITNESS WHEREOF, the parties hereto have executed this
Agreement on and as of the day and year first above written.



                                            ECOGEN INC.



                                            By:      ___________________________
                                            Name:    James P. Reilly, Jr.
                                            Title:   Chairman and Chief
                                                     Executive Officer



                                            By:      ___________________________
                                            Name:
                                            Title:



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