Exhibit 10.1

Execution Copy

STOCKHOLDER AGREEMENT

STOCKHOLDER AGREEMENT, dated as of August 13, 2007 (this “Agreement”), among the
stockholders listed on the signature page(s) hereto (collectively,
“Stockholders” and each individually, a “Stockholder”), Gensym Corporation, a
Delaware corporation (the “Company”) and Versata Enterprises, Inc., a Delaware
corporation (“Parent”). Capitalized terms used and not otherwise defined herein
shall have the respective meanings assigned to them in the Merger Agreement
referred to below.

WHEREAS, as of the date hereof, the Stockholders collectively own of record and
beneficially shares of capital stock of the Company, as set forth on Schedule I
hereto (such shares, or any other voting or equity of securities of the Company
hereafter acquired by any Stockholder prior to the termination of this
Agreement, being referred to herein collectively as the “Shares”);

WHEREAS, concurrently with the execution of this Agreement, Parent and the
Company are entering into an Agreement and Plan of Merger, dated as of the date
hereof (the “Merger Agreement”), pursuant to which, upon the terms and subject
to the conditions thereof, a subsidiary of Parent will be merged with and into
the Company, and the Company will be the surviving corporation (the “Merger”);
and

WHEREAS, as a condition to the willingness of Parent to enter into the Merger
Agreement, Parent has required that the Stockholders agree, and in order to
induce Parent to enter into the Merger Agreement, the Stockholders are willing
to enter into this Agreement.

NOW, THEREFORE, in consideration of the foregoing and the mutual covenants and
agreements contained herein, and intending to be legally bound hereby, the
parties hereby agree, severally and not jointly, as follows:

Section 1. Voting of Shares.

(a) Each Stockholder covenants and agrees that until the termination of this
Agreement in accordance with the terms hereof, at the Company Meeting or any
other meeting of the stockholders of the Company, however called, and in any
action by written consent of the stockholders of the Company, such Stockholder
will vote, or cause to be voted, all of his, her or its respective Shares (i) in
favor of adoption of the Merger Agreement and approval of the Merger
contemplated by the Merger Agreement, as the Merger Agreement may be modified or
amended from time to time in a manner not adverse to the Stockholders,
(ii) against any merger agreement or merger (other than the Merger Agreement and
the Merger), consolidation, combination, sale of substantial assets,
reorganization, recapitalization, dissolution, liquidation or winding up of or
by the Company or any other proposal, offer or agreement concerning any merger,
reorganization, consolidation, recapitalization, business combination,
liquidation, share exchange, sale of stock, sale of material assets or similar
business transaction involving the Company, any subsidiary of the Company or any
division of the Company and (iii) against any other action, agreement or
transaction submitted for the vote or written consent of Stockholders that would
reasonably be expected to impede, interfere with, delay, postpone, discourage,
frustrate the purposes of or adversely affect the Merger or the other
transactions contemplated by the Merger Agreement or this Agreement or the
performance by the Company of its obligations under the Merger Agreement or by
such Stockholder of its obligations under this Agreement.

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(b) Each Stockholder hereby irrevocably grants to, and appoints, Parent, and any
individual designated in writing by it, and each of them individually, as its
proxy and attorney-in-fact (with full power of substitution), for and in its
name, place and stead, to vote his, her or its Shares at any meeting of the
stockholders of the Company called with respect to any of the matters specified
in, and in accordance and consistent with this Section 1. Each Stockholder
understands and acknowledges that Parent is entering into the Merger Agreement
in reliance upon the Stockholder’s execution and delivery of this Agreement.
Each Stockholder hereby affirms that the irrevocable proxy set forth in this
Section 1(b) is given in connection with the execution of the Merger Agreement,
and that such irrevocable proxy is given to secure the performance of the duties
of such Stockholder under this Agreement. Except as otherwise provided for
herein, each Stockholder hereby (i) affirms that the irrevocable proxy is
coupled with an interest and may under no circumstances be revoked,
(ii) ratifies and confirms all that the proxies appointed hereunder may lawfully
do or cause to be done by virtue hereof and (iii) affirms that such irrevocable
proxy is executed and intended to be irrevocable in accordance with the
provisions of Section 212(e) of the Delaware General Corporation Law.
Notwithstanding any other provisions of this Agreement, the irrevocable proxy
granted hereunder shall automatically terminate upon the termination of this
Agreement.

(c) Each Stockholder covenants and agrees that until the termination of this
Agreement in accordance with the terms hereof, at the Company Meeting or any
other meeting of the stockholders of the Company, however called, and in any
action by written consent of the stockholders of the Company, such Stockholder
shall appear at each such meeting or otherwise cause the Shares as to which such
Stockholder controls the right to vote to be counted as present thereat for
purposes of calculating a quorum.

(d) The obligations of each Stockholder specified in this Section 1 shall,
subject to Section 6, apply whether or not the Merger or any action described
above is recommended by the Board of Directors of the Company.

Section 2. Transfer of Shares. Each Stockholder covenants and agrees that such
Stockholder will not directly or indirectly (i) sell, assign, transfer
(including by merger, testamentary disposition, interspousal disposition
pursuant to a domestic relations proceeding or otherwise by operation of law),
pledge, encumber or otherwise dispose of any of the Shares, (ii) deposit any of
the Shares into a voting trust or enter into a voting agreement or arrangement
with respect to the Shares or grant any proxy or power of attorney with respect
thereto which is inconsistent with this Agreement or (iii) enter into any
contract, option or other arrangement or undertaking with respect to the direct
or indirect sale, assignment, transfer (including by merger, testamentary
disposition, interspousal disposition pursuant to a domestic relations
proceeding or otherwise by operation of law) or other disposition of any Shares.

Section 3. Representations and Warranties of the Stockholders. Each Stockholder
on its own behalf hereby severally represents and warrants to Parent with
respect to itself and its, his or her ownership of the Shares as follows:

 

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(a) Ownership of Shares. The Stockholder beneficially owns all of the Shares as
set forth on Schedule I hereto and has good and marketable title to such Shares,
free and clear of any claims, liens, encumbrances and security interests
whatsoever. The Stockholder owns no shares of Common Stock other than the Shares
as set forth on Schedule I hereto. The Stockholder has sole voting power,
without restrictions, with respect to all of the Shares.

(b) Power, Binding Agreement. The Stockholder has the legal capacity and all
requisite power and authority to enter into and perform all of its obligations,
under this Agreement. This Agreement has been duly and validly executed and
delivered by the Stockholder and constitutes a valid and binding obligation of
the Stockholder, enforceable against the Stockholder in accordance with its
terms.

(c) No Conflicts. The execution and delivery of this Agreement do not, and the
consummation of the transactions contemplated hereby will not, conflict with or
result in any violation of, or default (with or without notice or lapse of time,
or both) under, or give rise to a right of termination, cancellation or
acceleration of any obligation or to loss of a material benefit under, any
provision of any loan or credit agreement, note, bond, mortgage, indenture,
lease, or other agreement, instrument, permit, concession, franchise, license,
judgment, order, decree, statute, law, ordinance, rule or regulation applicable
to the Stockholder, the Shares or any of the Stockholder’s properties or assets.
Except as expressly contemplated hereby, the Stockholder is not a party to, and
the Shares are not subject to or bound in any manner by, any contract or
agreement relating to the Shares, including without limitation, any voting
agreement, option agreement, purchase agreement, stockholders’ agreement,
partnership agreement or voting trust. Except for any informational filings with
the Securities and Exchange Commission, no consent, approval, order or
authorization of, or registration, declaration or filing with, any court,
administrative agency or commission or other governmental authority or
instrumentality, domestic, foreign or supranational, is required by or with
respect to the Stockholder in connection with the execution and delivery of this
Agreement or the consummation by the Stockholder of the transactions
contemplated hereby.

Section 4. No Solicitation. Prior to the termination of this Agreement in
accordance with its terms, each Stockholder agrees, in its individual capacity
as a stockholder of the Company, that (i) it will not, nor will it authorize or
permit any of its employees, agents and representatives to, directly or
indirectly, (a) initiate, solicit or encourage any inquiries or the making of
any Acquisition Proposal, (b) enter into any agreement with respect to any
Acquisition Proposal, or (c) participate in any discussions or negotiations
regarding, or furnish to any person any information with respect to, or take any
other action to facilitate any inquiries or the making of any proposal that
constitutes, or may reasonably be expected to lead to, any Acquisition Proposal,
and (ii) it will notify Parent as soon as possible if any such inquiries or
proposals are received by, any information or documents is requested from, or
any negotiations or discussions are sought to be initiated or continued with, it
or any of its affiliates in its individual capacity.

Section 5. Stock Dividends, etc. In the event of a stock split, stock dividend
or distribution, or any change in the common stock by reason of any split-up,
reverse stock split, recapitalization, combination, reclassification, exchange
of shares or the like, the term “Shares” shall be deemed to refer to and include
such shares as well as all such stock dividends and

 

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distributions and any securities into which or for which any or all of such
shares may be changed or exchanged or which are received in such transaction;
provided that the foregoing shall not prevent the conversion of any of the
Shares into the right to receive Merger Consideration pursuant to the Merger in
accordance with the terms of the Merger Agreement.

Section 6. Termination. This Agreement shall terminate upon the earlier to occur
of (i) the Effective Time or (ii) any termination of the Merger Agreement in
accordance with the terms thereof; provided that no such termination shall
relieve any party of liability for a willful breach hereof prior to termination.

Section 7. Specific Performance. The parties hereto agree that irreparable
damage would occur in the event any provision of this Agreement was not
performed in accordance with the terms hereof and that the parties shall be
entitled to specific performance of the terms hereof, in addition to any other
remedy at law or in equity.

Section 8. Fiduciary Duties. Each Stockholder is signing this Agreement solely
in such Stockholder’s capacity as an owner of his, her or its respective Shares,
and nothing herein shall prohibit, prevent or preclude such Stockholder from
taking or not taking any action in his or her capacity as an officer or director
of the Company, to the extent permitted by the Merger Agreement.

Section 9. Consent and Waiver. Each Stockholder hereby gives any consents or
waivers that are reasonably required for the consummation of the Merger under
the terms of any agreement to which such Stockholder is a party or pursuant to
any rights such Stockholder may have in its capacity as a Stockholder of the
Company.

Section 10. Waiver of Appraisal Rights. To the fullest extent permitted by
applicable law, each Stockholder hereby waives any rights of appraisal or rights
to dissent from the Merger that it may have under applicable law.

Section 11. Miscellaneous.

(a) Entire Agreement. This Agreement constitutes the entire agreement between
the parties hereto with respect to the subject matter hereof and supersedes all
prior agreements and understandings, both written and oral, between the parties
with respect thereto. This Agreement may not be amended, modified or rescinded
except by an instrument in writing signed by each of the parties hereto.

(b) Severability. If any term or other provision of this Agreement is invalid,
illegal or incapable of being enforced by any rule of law, or public policy, all
other conditions and provisions of this Agreement shall nevertheless remain in
full force and effect. Upon such determination that any term or other provision
is invalid, illegal or incapable of being enforced, the parties hereto shall
negotiate in good faith to modify this Agreement so as to effect the original
intent of the parties as closely as possible to the fullest extent permitted by
applicable law in a mutually acceptable manner in order that the terms of this
Agreement remain as originally contemplated to the fullest extent possible.

 

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(c) Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of Delaware without regard to the
principles of conflicts of law thereof.

(d) Counterparts. This Agreement may be executed in counterparts, each of which
shall be deemed an original and all of which together shall constitute one and
the same instrument.

(e) Notices. All notices and other communications hereunder shall be in writing
and shall be deemed duly delivered (i) three business days after being sent by
registered or certified mail, return receipt requested, postage prepaid, or
(ii) one business day after being sent for next business day delivery, fees
prepaid, via a reputable nationwide overnight courier service, in each case to
the intended recipient as set forth below:

(i) if to a Stockholder to the address set forth on the respective signature
page of this Agreement;

(ii) if to the Parent to:

Versata Enterprises, Inc.

6011 West Courtyard Drive, Suite 300

Austin, TX 78730

Attn: Lance A. Jones

Telecopy: 512-874-3502

with a copy to:

Haynes and Boone, LLP

901 Main Street, Suite 3100

Dallas, TX 75202

Attn: Dennis R. Cassell

Telecopy: 214-200-0788

(iii) if to the Company to:

Gensym Corporation

52 Second Avenue

Burlington, MA 01803

Attn: President

Telecopy: (781) 265-7101

with a copy to:

Wilmer Cutler Pickering Hale and Dorr LLP

60 State Street

Boston, MA 02109

Attn: David Westenberg, Esq.

         Edward Young, Esq.

Telecopy: (617) 526-6000

 

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(f) No Third Party Beneficiaries. This Agreement is not intended, and shall not
be deemed, to confer any rights or remedies upon any person other than the
parties hereto and their respective successors and permitted assigns, to create
any agreement of employment with any person or to otherwise create any
third-party beneficiary hereto.

(g) Assignment. Neither this Agreement nor any of the rights, interests or
obligations under this Agreement may be assigned or delegated, in whole or in
part, by operation of law or otherwise by any of the parties hereto without the
prior written consent of the other parties, and any such assignment without such
prior written consent shall be null and void, except that the Parent may assign
this Agreement to any direct or indirect wholly owned subsidiary of the Parent
without the consent of the Company or the Stockholder, provided that the Parent
shall remain liable for all of its obligations under this Agreement. Subject to
the preceding sentence, this Agreement shall be binding upon, inure to the
benefit of, and be enforceable by, the parties hereto and their respective
successors and permitted assigns.

(h) Interpretation. When reference is made in this Agreement to a Section, such
reference shall be to a Section of this Agreement, unless otherwise indicated.
The headings contained in this Agreement are for convenience of reference only
and shall not affect in any way the meaning or interpretation of this Agreement.
The language used in this Agreement shall be deemed to be the language chosen by
the parties hereto to express their mutual intent, and no rule of strict
construction shall be applied against any party. Whenever the context may
require, any pronouns used in this Agreement shall include the corresponding
masculine, feminine or neuter forms, and the singular form of nouns and pronouns
shall include the plural, and vice versa. Any reference to any federal, state,
local or foreign statute or law shall be deemed also to refer to all rules and
regulations promulgated thereunder, unless the context requires otherwise.
Whenever the words “include,” “includes” or “including” are used in this
Agreement, they shall be deemed to be followed by the words “without
limitation.” No summary of this Agreement prepared by the parties shall affect
in any way the meaning or interpretation of this Agreement.

(i) Submission to Jurisdiction. Each of the parties to this Agreement
(i) consents to submit itself to the personal jurisdiction of any state or
federal court sitting in the State of Delaware in any action or proceeding
arising out of or relating to this Agreement or any of the transactions
contemplated by this Agreement, (ii) agrees that all claims in respect of such
action or proceeding may be heard and determined in any such court, (iii) agrees
that it will not attempt to deny or defeat such personal jurisdiction by motion
or other request for leave from any such court and (iv) agrees not to bring any
action or proceeding arising out of or relating to this Agreement or any of the
transactions contemplated by this Agreement in any other court. Each of the
parties hereto waives any defense of inconvenient forum to the maintenance of
any action or proceeding so brought and waives any bond, surety or other
security that might be required of any other party with respect thereto. Any
party hereto may make service on another party by sending or delivering a copy
of the process to the party to be served at the address and in the manner
provided for the giving of notices in Section 11(e). Nothing in this Section,
however, shall affect the right of any party to serve legal process in any other
manner permitted by law.

 

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(j) WAIVER OF JURY TRIAL. EACH OF THE PARENT, THE COMPANY AND EACH STOCKHOLDER
HEREBY IRREVOCABLY WAIVES ALL RIGHTS TO TRIAL BY JURY IN ANY ACTION, PROCEEDING
OR COUNTERCLAIM (WHETHER BASED ON CONTRACT, TORT OR OTHERWISE) ARISING OUT OF OR
RELATING TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY OR THE
ACTIONS OF THE PARENT, THE COMPANY OR EACH STOCKHOLDER IN THE NEGOTIATION,
ADMINISTRATION, PERFORMANCE AND ENFORCEMENT OF THIS AGREEMENT.

[Signature Page to follow]

 

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IN WITNESS WHEREOF, each of the parties hereto has caused this Agreement to be
signed individually or by its respective duly authorized officer as of the date
first written above.

 

GENSYM CORPORATION By:  

/s/ Robert B. Ashton

Name:   Robert B. Ashton Title:   President and Chief Executive Officer VERSATA
ENTERPRISES, INC. By:  

/s/ Sean Fallon

Name:   Sean Fallon Title:   Vice President of Finance and Chief Financial
Officer

[Signature Page to Stockholder Agreement]

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STOCKHOLDERS:

/s/ Robert B. Ashton

Robert B. Ashton

 

Address

 

Address

/s/ John A. Shane

John A. Shane

 

Address

 

Address

/s/ David A. Smith

David A. Smith

 

Address

 

Address

/s/ Thomas E. Swithenbank

Thomas E. Swithenbank

 

Address

 

Address

[Signature Page to Stockholder Agreement]

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Schedule I

 

Stockholder

  

Number of Shares of

Common Stock Owned

Robert A. Ashton

   1,310,311

John A. Shane

   47,875

David A. Smith

   13,171

Thomas E. Swithenbank

   20,286