i 2 to satisfy the obligations of Company. In the event Mr. Fischel is required by legal process to disclose any Confidential Information, he shall give prompt notice thereof to Company to allow Company to object to such process, obtain a protective...

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                                                                   EXHIBIT 10.57


                CONFIDENTIALITY AND PROPRIETARY RIGHTS AGREEMENT


      THIS CONFIDENTIALITY AND PROPRIETARY RIGHTS AGREEMENT (the "Agreement") is
entered into as of December 31, 1998 by and between Lexecon Inc. ("Company") and
Xxxxxx X. Xxxxxxx ("Xx. Xxxxxxx").

      WHEREAS, pursuant to a Contribution Agreement (the "Contribution
Agreement"), dated as of December 31, 1998, by and among Nextera Enterprises,
Inc. ("Nextera"), Company and the shareholders of Company (including Xx.
Xxxxxxx), such shareholders are contributing all of the outstanding shares of
capital stock of Company to Nextera (the "Transaction"); and

      WHEREAS, Xx. Xxxxxxx is a key employee of the Company and Nextera deems
Xx. Xxxxxxx'x covenants contained herein to be material and significant to
Company's success; and

      WHEREAS, the execution of this Agreement is a condition to the
consummation by Nextera of the Transaction;

      NOW, THEREFORE, the parties hereto agree as follows:

      1.    Access to Confidential Information. Xx. Xxxxxxx'x services
previously rendered to Company have placed him in a position of confidence and
trust with Company and have allowed and may continue to allow him access to
Confidential Information. As used herein, "Confidential Information" shall mean
information and compilations of information relating to the business of Company
including, but not limited to, information regarding any trade secrets,
proprietary knowledge, operating procedures, finances, financial condition,
organization, employees, customer lists, client lists, suppliers, distributors,
agents, and other personnel, business activities, budgets, strategic or
financial plans, objectives, marketing plans, documents, products, services,
price and price lists, operating and training materials, data bases and analyses
and all other documents relating thereto or strategies of Company. However,
Confidential Information will not include any information which is or becomes
available in the public domain or which is or becomes known to the public or the
industry by any means other than disclosure by Xx. Xxxxxxx.

      2.    Covenant as to Nondisclosure or Use of Confidential Information. Xx.
Xxxxxxx agrees that he will maintain the Confidential Information in strictest
confidence and, unless required to do so by legal process (such as subpoena),
not disclose to any individual or business enterprise of any nature, or use for
his own personal use or financial gain, whether individually or on behalf of
another person, firm, corporation or entity, any Confidential Information.
Without limiting the generality of the foregoing, Xx. Xxxxxxx agrees that
Company's agreements with other persons may include agreements that impose
obligations or restrictions regarding the confidential nature of work pursuant
to such an agreement. Xx. Xxxxxxx agrees to be bound by all such obligations and
restrictions made known to him, and to do whatever is reasonably necessary 


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to satisfy the obligations of Company. In the event Xx. Xxxxxxx is required by
legal process to disclose any Confidential Information, he shall give prompt
notice thereof to Company to allow Company to object to such process, obtain a
protective order or take other reasonable action.

      3.    Assignment of Inventions. To the maximum extent permitted by law,
Xx. Xxxxxxx does hereby assign and transfer to Company his entire right, title
and interest in and to all inventions including, but not limited to, designs,
discoveries, inventions, improvements, formulas, ideas, devices, techniques,
processes, writings, trade secrets, trademarks, trademark applications, patents,
copyrights and all other intellectual property rights including but not limited
to notes, records, reports, software, plans, memoranda and other tangible
information relating to such intellectual property, whether or not subject to
protection under applicable laws, which he solely or jointly with others
conceived, made or acquired at any time during his employment with Company prior
to the date hereof and which relate in any manner to the actual or demonstrably
anticipated business, products, processes, work, operations, research and
development or other activities of Company, or result from any work performed by
Xx. Xxxxxxx for or on behalf of Company ("Inventions"), but excluding those
developed in connection with his activities at The University of Chicago (or
another institution of higher learning). All Inventions shall be the sole
property of Company.

            Notwithstanding anything in this Agreement to the contrary, Company
acknowledges that Xx. Xxxxxxx has (and in the future shall be entitled to) write
books and articles for publication under his own name and is (and shall be)
entitled to receive and retain any royalties therefrom, so long as such books or
articles do not disclose or exploit any confidential or proprietary information
of Company or its clients.

      4.    Disclosure of Inventions, Patents, Copyrights and Other Rights. Xx.
Xxxxxxx agrees:

            4.1   Upon request, to promptly execute a written assignment of
title to Company for any Invention required to be assigned by Section 3
("assignable invention") and he will preserve any such assignable invention as
Confidential Information.

            4.2   Upon request and at Company's expense, to assist Company or
its nominee in every reasonable way to obtain for Company's or its nominee's
benefit, patents, copyrights, mask work rights and other statutory rights
("Statutory Rights") for such assignable inventions in any and all countries,
which inventions shall be and remain the sole and exclusive property of Company
or its nominee whether or not patented, copyrighted or the subject of a mask
work right. Xx. Xxxxxxx shall execute such papers and perform such lawful acts
as Company deems reasonably necessary to exercise all rights, title and interest
in such Statutory Rights.

            4.3   To execute and deliver to Company or its nominee upon request
all documents, including applications for and assignments of Statutory Rights to
be issued therefor, as Company determines are necessary or desirable to apply
for and obtain Statutory Rights on 


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such assignable inventions in any and all countries and/or to protect the
interest of Company or its nominee in Statutory Rights and to vest title thereto
in Company or its nominee.

      5.    Return of Records, Equipment and Confidential Information. Upon
request by Company, Xx. Xxxxxxx shall promptly return to Company: (i) all
Confidential Information and all documents, records, procedures, books,
notebooks, and any other documentation in any form whatsoever (including, but
not limited to, written, audio, video or electronic) containing any information
pertaining to Company which includes Confidential Information, including any and
all copies of such documentation then in his possession or control regardless of
whether such documentation was prepared or compiled by Xx. Xxxxxxx, Company,
employees of Company, representatives, agents, or independent contractors, and
(ii) all equipment or tangible personal property entrusted to Xx. Xxxxxxx by
Company. Xx. Xxxxxxx will not retain any original, copy, description, document,
data base or other form of media that contains or relates to any Confidential
Information whether produced by him or otherwise. Without limiting the
generality of the foregoing, upon request Xx. Xxxxxxx shall permanently delete
all Confidential Information from all computers, disks, CD-ROMS, tapes, and
other media owned or used by or accessible to him, other than from any of the
foregoing owned, used or controlled by Company. Xx. Xxxxxxx acknowledges that
all Confidential Information and all such documentation, copies of such
documentation, equipment, and tangible personal property are and shall at all
times remain the sole and exclusive property of Company.

      6.    Post-Employment Cooperation. Xx. Xxxxxxx shall cooperate and assist
Company at Company's reasonable request and expense in any dispute, controversy,
or litigation to which Company is a party and with respect to which he obtained
knowledge while employed by Company or any of its predecessors, affiliates,
successors, or assigns, including, but not limited to, his participation in any
court or arbitration proceedings, giving of testimony, signing of affidavits, or
such other personal cooperation as counsel for Company shall request.

      7.    Commercial Endeavors. Other than his academic positions at The
University of Chicago (or academic positions at another university or
institution of higher education), Xx. Xxxxxxx agrees not to devote a material
amount of time to any commercial endeavor at any time when he is bound by the
provisions of Section 6.1 of the Contribution Agreement.

      8.    Remedies. Xx. Xxxxxxx has carefully considered the nature and extent
of the restrictions imposed by the covenants in this Agreement and agrees that
they are fair and reasonable and such restrictions will not prevent him from
earning a livelihood. In view of the position of confidence and trust which Xx.
Xxxxxxx has enjoyed with Company and his relationship with the customers,
suppliers and employees of Company, and recognizing both the access to
confidential financial and other information which he has had and the fact that
his covenants herein constitute material provisions of the Transaction, Xx.
Xxxxxxx expressly acknowledges that the restrictive covenants set forth in this
Agreement are necessary in order to protect and maintain the proprietary
interests, goodwill and other legitimate business interests of Company. Xx.
Xxxxxxx further acknowledges that (i) it would be difficult to calculate damages
to Company 


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from any breach of his obligations under this Agreement, (ii) that injury to
Company from any such breach would be irreparable and impossible to measure, and
(iii) that the remedy at law for any breach or threatened breach of this
Agreement would therefore be an inadequate remedy and, accordingly, Company
shall, in addition to all other available remedies (including without limitation
seeking such damages as it can show it has sustained by reason of such breach
and/or the exercise of all other rights it has under this Agreement), be
entitled to injunctive and other similar equitable remedies without the
necessity of showing actual damages or posting bond.

      9.    General Provisions.

      (a)   Services performed by Xx. Xxxxxxx for Company after the date of this
Agreement shall be as an employee. Xx. Xxxxxxx shall be paid at his hourly rate
multiplied by the number of billable hours he works on any client matter;
provided that the first $500,000 of total payments otherwise payable to Xx.
Xxxxxxx pursuant to this Section shall instead be paid to him at 25% of his
hourly rate (i.e., he will receive $125,000 in respect of his first $500,000 of
xxxxxxxx). Xx. Xxxxxxx authorizes Company to deduct and withhold from all
compensation to be paid to Xx. Xxxxxxx any and all sums required to be deducted
or withheld by Company pursuant to the provisions of any federal, state, or
local law, regulation, ruling or ordinance, including, but not limited to,
income tax withholding and payroll taxes. So long as Xx. Xxxxxxx is employed
with Company, Xx. Xxxxxxx will be entitled to such benefits as are provided to
the executive employees of Company (vacation, medical, etc.), in accordance with
and subject to Company's policies and guidelines as in effect from time to time,
but in no event will such benefits be less than those provided to executive
officers of Nextera.

      (b)   All notices hereunder shall be deemed to have been duly given when
delivered, addressed as follows (or at such other address as the addressed party
may have substituted by notice pursuant to this Section):

            If to Xx. Xxxxxxx:   000 Xxxxxxxx Xxxx
                                 Xxxxxxxx Xxxx, XX 00000

            If to Company:       Lexecon Inc.
                                 000 X. Xxxxxxxx Xxx., Xxxxx 0000
                                 Xxxxxxx, XX 00000
                                 Attn:  Xxxxxx X. Xxxxxxxxxx
                                 Fax: (000) 000-0000


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                                 with a copy to:

                                 Maron & Sandler
                                 000 Xxxxxx Xxxxx
                                 Xxx Xxxxxxx, Xxxxxxxxxx 00000
                                 Attn: Xxxxxxx X. Xxxxx, Esq.
                                 Fax: (000) 000-0000

      (c)   This Agreement constitutes the entire agreement between the parties
relating to the subject matter hereof.

      (d)   Every provision of this Agreement is intended to be severable from
every other provision of this Agreement. If any provision of this Agreement is
held to be unreasonable or excessive in scope or duration, that provision will
be deemed to be reformed to the minimum extent necessary so that such provision
as reformed may and shall be enforced to the maximum extent permitted by law. If
any provision of this Agreement is held to be void or unenforceable, in whole or
in part, the remaining provisions will remain in full force and effect, unless
the remaining provisions are so eviscerated by such holding that they do not
reflect the intent of the parties in entering into this Agreement.

      (e)   Any waiver of any breach of any provision of this Agreement will not
be deemed to be a waiver of any subsequent breach of that provision, or of any
breach of any other provision of this Agreement. No failure or delay in
exercising any right under any provision of this Agreement will be deemed a
waiver of that or any other right.

      (f)   Each of the parties has had the opportunity to be represented by
counsel in the negotiation and preparation of this Agreement. The parties agree
that this Agreement is to be construed as jointly drafted. Accordingly, this
Agreement will be construed according to the fair meaning of its language, and
the rule of construction that ambiguities are to be resolved against the
drafting party will not be employed in the interpretation of this Agreement.

      (g)   Transmission by facsimile of an executed counterpart signature page
hereof by a party hereto shall constitute due execution and delivery of this
Agreement by such party.


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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed
by their duly authorized representatives, as of the date first written above.


                                       COMPANY:

                                       LEXECON INC., an Illinois corporation



                                       By:  /S/ XXXXXX X. XXXXXXXXXX        
                                            ------------------------------------
                                            Name:  Xxxxxx X. Xxxxxxxxxx
                                            Title:



                                        /S/ XXXXXX X. XXXXXXX                   
                                       -----------------------------------------
                                       XX. XXXXXX X. XXXXXXX


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