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Exhibit 10.23    
    


 
 

PLEDGE AGREEMENT    
    













Dated:
August 5, 2003 














        To
secure the prompt, punctual, and faithful performance of all and each of the Obligations (as that term is defined herein) of the undersigned, ASPEN
TECHNOLOGY, INC., a Delaware corporation, with offices at Ten Canal Park, Cambridge, Massachusetts 02141 (hereinafter, the "Borrower") to SILICON
VALLEY BANK, a California-chartered bank, with its principal office located at 3003 Tasman Drive, Santa Clara, California 95054 and with a loan production office located at One
Newton Executive Park, Suite 200, 2221 Washington Street, Newton, Massachusetts 02462 (hereinafter, the "Lender"), the Borrower hereby grants to the Lender a security interest in and to, and assigns,
pledges, and delivers to the Lender the following property, and all products, proceeds, substitutions, additions, interest, dividends, and other distributions (including, without limitation, stock
splits) in respect thereto, and all books, records, and papers relating to the foregoing (all of which is referred to hereinafter as the "Collateral"): 




Certificate
No.            , representing 66% of the common stock of HYPROTECH COMPANY, a corporation organized under the laws of Nova Scotia, Canada 





        1.     The
Borrower represents that the Collateral is held and owned by the Borrower free and clear of all liens, encumbrances, attachments, security interests, pledges, and
charges, and if the Collateral is securities, is fully paid for and nonassessable. 


        2.     The
Borrower shall: 



        (a)   execute
all such instruments, documents, and papers, and will do all such acts as the Lender may request from time to time to carry into effect the provisions and intent
of this Agreement, including, without limitation, the execution of stop transfer orders, stock powers, notifications to obligors on the Collateral, the providing of notifications in connection with
book entry securities or general intangibles, and the providing of instructions to the issuers of uncertificated securities, and will do all such other acts as the Lender may request with respect to
the perfection and protection of the security interest granted herein and the assignment effected hereby; 


        (b)   keep
the Collateral free and clear of all liens, encumbrances, attachments, security interests, pledges, and charges other than those created by this Agreement; 


        (c)   deliver
to the Lender, if and when received by the Borrower, any item representing or constituting any of the Collateral, including, without limitation, all cash
dividends (except that the Borrower may collect such cash dividends prior to the occurrence of an Event of Default) and all stock certificates whether now existing or hereafter received as a result of
any stock dividends, stock splits or other transaction; 


        (d)   upon
the request of the Lender after the occurrence of an Event of Default which is not cured, cause the issuer of any uncertificated securities comprising any of the
Collateral to issue certificates with respect thereto; 


        (e)   upon
the request of the Lender after the occurrence of an Event of Default which is not cured, cause certificated securities comprising any of the Collateral to be
issued in the name of the Lender, as pledgee; 


        (f)    not
cause or permit any of the Collateral presently evidenced by written certificates to be converted to uncertificated securities; 



        (g)   not
exercise any right with respect to the Collateral which would dilute or adversely affect the Lender's rights in the Collateral; 






 




        (h)   not
file any affidavit for replacement of lost stock certificates or bonds; and 


        (i)    not
vote the Collateral in favor of or consent to any resolution which might 




	(i)
	impose
any restrictions upon the sale, transfer, or disposition of the Collateral; or



	(ii)
	result
in the issuance of any additional shares of stock of any class; or



	(iii)
	vest
additional powers, privileges, preferences, or priorities to any other class of stock. 






        3.     Upon
the occurrence of any one or more Events of Default, (as defined in a certain Loan and Security Agreement of even date (as may be amended, the "Loan Agreement"),
which Events of Default are not cured to the satisfaction of the Lender, any and all Obligations of the Borrower to the Lender shall become immediately due and payable at the option of the Lender and
without notice or demand, in addition to which the Lender may exercise the Lender's rights and remedies upon default, as provided in the Loan Agreement. 


        4.     The
Borrower hereby designates the Lender as and for the attorney-in- fact of the Borrower to, upon or after the occurrence of an Event of
Default: endorse in favor of the Lender any of the Collateral; cause the transfer of any of the Collateral in such name as the Lender may, from time to time, determine; cause the issuance of
certificates for book entry and/or uncertificated securities; and make demand and initiate actions to enforce the Lender's rights with regard to any of the Collateral. The Lender may take such action
with respect to the Collateral as the Lender may reasonably determine to be necessary to protect and preserve its interest in the Collateral. The Lender shall also have and may exercise at any time
all rights, remedies, powers, privileges, and discretions of the Borrower with respect to and under the Collateral, provided, however, the Lender shall have no right to exercise any voting rights
available to holders of the Collateral at any time the Collateral is held by the Lender solely as pledgee hereunder, and whether or not an Event of Default has occurred. All of the rights, remedies,
powers, privileges and discretions included in this Paragraph 5, may only be exercised by the Lender upon or after the occurrence of an Event of Default. The within designation, being coupled
with an interest, is irrevocable until the within instrument is terminated by a written instrument executed by a duly authorized officer of the Lender. The power of attorney shall not be affected by
subsequent disability or incapacity of the Borrower. The Lender shall not be liable for any act or omission to act pursuant to this Paragraph except for any act or omission to act which is in actual
bad faith, intentional wrong-doing, or gross negligence. 


        5.     As
used herein, the following terms have the following meanings: 



        (a)   "Obligation"
and "Obligations" are defined as provided in the Loan Agreement. 


        (b)   "Events
of Default" are defined as provided in the Loan Agreement. 




        6.     Except
to the extent provided in the Loan Agreement, the Borrower (a) waives presentment, demand, notice, and protest with respect to the Obligations and the
Collateral; and (b) waives any delay on the part of the Lender without notice to or consent from the Borrower; and (c) assents to any indulgence or waiver which the Lender may grant or
give any other person liable or obliged to the Lender for or on the Obligations without notice to or consent from the Borrower; and (d) authorizes the Lender to alter, amend, cancel, waive, or
modify any term or condition of the obligations of any other person liable or obligated to the Lender for or on the Obligations, without notice to or consent from the Borrower; and (e) agrees
that no release of any property securing the Obligations, without notice to or consent from the Borrower, shall affect the rights of the Lender with respect to the Collateral hereunder; and, if
entitled thereto, (f) waives the right to notice and/or hearing prior to the Lender's exercising of the Lender's rights and remedies hereunder upon the occurrence and during the continuance of
an Event of Default. 


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        7.     The
Lender shall have no duty as to the collection or protection of the Collateral or any income or distribution thereon, beyond the safe custody of such of the
Collateral as may come into the possession of the Lender and shall have no duty as to the preservation of rights against prior parties or any other rights pertaining thereto. The Lender's Rights and
Remedies may be exercised without resort or regard to any other source of satisfaction of the Obligations. 


        8.     This
Agreement shall be binding upon the Borrower and upon the Borrower's administrators, successors, and assigns, and shall inure to the benefit of the Lender and the
Lender's successors and assigns. 


        9.     This
Agreement and all other instruments executed in connection with the Obligations incorporate all discussions and negotiations between the Borrower and the Lender
concerning the matters included herein and in such other instruments. No such discussions or negotiations shall limit, modify, or otherwise affect the provisions hereof. No modification, amendment, or
waiver of any provision of the within Agreement or of any provision of any other agreement between the Borrower and the Lender shall be effective unless executed in writing by the party to be charged
with such modification, amendment of waiver, and if such party be the Lender, then by a duly authorized officer thereof. 


        EXECUTED as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first written above. 



	

 	
 	
ASPEN TECHNOLOGY, INC.
	

 	
 	

 	
 	

 	
 	

 
	 	 	By:	 	/s/  CHARLES F. KANE      

	 	 	 	 	Name:	 	Charles F. Kane
	 	 	 	 	Title:	 	CFO




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Exhibit 10.23


PLEDGE AGREEMENT