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Exhibit 10.13  


STARENT NETWORKS, CORP.  


 
  Restricted Stock Agreement
Granted Under 2000 Stock Incentive Plan    
    


        AGREEMENT
made this 8th day of February, 2007, between Starent Networks, Corp., a Delaware corporation (the "Company"), and Paul J. Milbury (the "Participant"). 



        For
valuable consideration, receipt of which is acknowledged, the parties hereto agree as follows: 


        1.    Purchase of Shares.    The Company shall issue and sell to the Participant, and the Participant shall purchase
from the Company, subject to the terms and conditions set forth in this Agreement and in the Company's 2000 Stock Incentive Plan (the "Plan"), 365,729 shares (the "Shares") of common stock, $0.001 par
value, of the Company ("Common Stock"), at a purchase price of $0.01 per share. The aggregate purchase price for the Shares shall be paid by the Participant by check payable to the order of the
Company or such other method as may be acceptable to the Company. Upon receipt by the Company of payment for the Shares, the Company shall issue to the Participant one or more certificates in the name
of the Participant for that number of Shares purchased by the Participant. The Participant agrees that the Shares shall be subject to the Purchase Option set forth in Sections 2 and 5 of this
Agreement and the restrictions on transfer set forth in Section 4 of this Agreement. 


        2.    Purchase Option.    



        (a)   In
the event that the Participant ceases to be employed by the Company for any reason or no reason, with or without Cause, prior to  July 1, 2009, the Company shall have the right and option (the
"Purchase Option") to purchase from the Participant, for a sum of $0.01 per share
(the "Option Price"), some or all of the Unvested Shares (as defined below). 


        (b)   "Unvested
Shares" and "Vested Shares" at the time the Purchase Option becomes exercisable by the Company shall be as follows: 



	Period
 
	 	Vested

Shares
	 	Unvested

Shares

	February 8, 2007 to February 7, 2008	 	0	 	365,729
	February 8, 2008 to March 31, 2008	 	162,500	 	203,229
	April 1, 2008 to June 30, 2008	 	203,125	 	162,604
	July 1, 2008 to September 30, 2008	 	243,750	 	121,979
	October 1, 2008 to December 31, 2008	 	284,375	 	81,354
	January 1, 2009 to March 31, 2009	 	325,000	 	40,729
	April 1, 2009 to June 30, 2009	 	365,625	 	104
	On and after July 1, 2009	 	365,729	 	0






        (c)   For
purposes of this Agreement, employment with the Company shall include employment with a parent or subsidiary of the Company. 


        (d)   In
the event of an Acquisition (as defined in Section 2(f) below), then, immediately prior to the consummation of the Acquisition, the vesting of the
Participant's Shares (and the date referred to in Section 2(b) above) shall be accelerated by 12 months. In addition, the vesting of the Participant's Shares (and the date referred to in
Section 2(b) above) shall be accelerated by a further 12 months if, on or prior to the first anniversary of the date of the consummation of the Acquisition, the Participant's employment
with the Company or the acquiring or succeeding corporation is terminated for Good Reason (as defined in Section 2(f) below) by the Participant or is terminated without Cause (as defined in
Section 2(f) below) by the Company or the acquiring or succeeding corporation. 








 




        (e)   In
the event an Acquisition has not occurred and the Participant's employment with the Company is terminated without Cause by the Company, the vesting of the
Participant's Shares, to the extent they are not fully vested at such time, shall be accelerated such that an additional number of Shares equal to the lesser of (i) 162,500 and (ii) the
number of Shares for which the Participant has made a timely election under Section 83(b) of the Code with the Internal Revenue Service, shall become "Vested Shares" on the date of such
termination. 


        (f)    For
the purposes of this Agreement, 



        (1)   "Acquisition"
shall mean any (i) merger or consolidation which results in the voting securities of the Company outstanding immediately prior thereto representing
immediately thereafter (either by remaining outstanding or by being converted into voting securities of the surviving or acquiring entity (the "Acquiror")) less than a majority of the combined voting
power of the voting securities of the Company or the Acquiror outstanding immediately after such merger or consolidation, (ii) sale of all or substantially all of the assets of the Company or
(iii) sale of shares of capital stock of the Company, in a single transaction or series of related transactions, representing at least 80% of the voting power of the outstanding securities of
the Company. 


        (2)   "Cause"
shall mean willful misconduct by the Participant or willful failure by the Participant to perform his or her responsibilities to the Company (including, without
limitation, breach by the Participant of any provision of any employment, consulting, advisory, nondisclosure,
non-competition or other similar agreement between the Participant and the Company), as determined by the Company, which determination shall be conclusive. The Participant shall be
considered to have been discharged for "Cause" if the Company determines, within 30 days after the Participant's resignation, that discharge for cause was warranted. 


        (3)   "Good
Reason" shall mean shall mean any significant diminution in the Participant's title, authority, or responsibilities from and after such Acquisition or the
relocation of the place of business at which the Participant is principally located to a location that is greater than 50 miles from Tewksbury, Massachusetts. 





        3.    Exercise of Purchase Option and Closing.    



        (a)   The
Company may exercise the Purchase Option by delivering or mailing to the Participant (or his estate), within 90 days after the termination of the employment
of the Participant with the Company, a written notice of exercise of the Purchase Option. Such notice shall specify the number of Shares to be purchased. If and to the extent the Purchase Option is
not so exercised by the giving of such a notice within such 90-day period, the Purchase Option shall automatically expire and terminate effective upon the expiration of such
90-day period. 


        (b)   Within
10 days after delivery to the Participant of the Company's notice of the exercise of the Purchase Option pursuant to subsection (a) above, the
Participant (or his estate) shall, pursuant to the provisions of the Joint Escrow Instructions referred to in Section 7, tender to the Company at its principal offices the certificate or
certificates representing the Shares which the Company has elected to purchase in accordance with the terms of this Agreement, duly endorsed in blank or with duly endorsed stock powers attached
thereto, all in form suitable for the transfer of such Shares to the Company. Promptly following its receipt of such certificate or certificates, the Company shall pay to the Participant the aggregate
Option Price for such Shares (provided that any delay in making such payment shall not invalidate the Company's exercise of the Purchase Option with respect to such Shares). 



        (c)   After
the time at which any Shares are required to be delivered to the Company for transfer to the Company pursuant to subsection (b) above, the Company shall not
pay any 



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dividend
to the Participant on account of such Shares or permit the Participant to exercise any of the privileges or rights of a stockholder with respect to such Shares, but shall, in so far as
permitted by law, treat the Company as the owner of such Shares. 



        (d)   The
Option Price may be payable, at the option of the Company, in cancellation of all or a portion of any outstanding indebtedness of the Participant to the Company or
in cash (by check) or both. 


        (e)   The
Company shall not purchase any fraction of a Share upon exercise of the Purchase Option, and any fraction of a Share resulting from a computation made pursuant to
Section 2 of this Agreement shall be rounded to the nearest whole Share (with any one-half Share being rounded upward). 


        (f)    The
Company may assign its Purchase Option to one or more persons or entities. 




        4.    Restrictions on Transfer.    The Participant shall not sell, assign, transfer, pledge, hypothecate or otherwise
dispose of, by operation of law or otherwise (collectively "transfer"): 



        (a)   any
Shares, or any interest therein, that are subject to the Purchase Option, except that the Participant may transfer such Shares (i) to or for the benefit of
any spouse, child or grandchild of the Participant, or to a trust for their benefit, provided that such Shares shall remain subject to this Agreement
(including without limitation the restrictions on transfer set forth in this Section 4, the Purchase Option and the right of first refusal set forth in Section 5) and such permitted
transferee shall, as a condition to such transfer, deliver to the Company a written instrument confirming that such transferee shall be bound by all of the terms and conditions of this Agreement or
(ii) as part of the sale of all or substantially all of the Shares of capital stock of the Company (including pursuant to a merger or consolidation),  provided that, in accordance with the Plan, the
securities or other property received by the Participant in connection with such transaction shall
remain subject to this Agreement; or 


        (b)   any
Shares, or any interest therein, that are no longer subject to the Purchase Option, except in accordance with Section 5 below. 




        5.    Right of First Refusal.    



        (a)   If
the Participant proposes to transfer any Shares that are no longer subject to the Purchase Option (either because they are no longer Unvested Shares or because the
Purchase Option expired unexercised), then the Participant shall first give written notice of the proposed transfer (the "Transfer Notice") to the Company. The Transfer Notice shall name the proposed
transferee and state the number of such Shares he proposes to transfer (the "Offered Shares"), the price per share and all other material terms and conditions of the transfer. 


        (b)   For
30 days following delivery to the Company of such Transfer Notice, the Company shall have the option to purchase all (but not less than all) of the Offered
Shares at the price and upon the terms set forth in the Transfer Notice. In the event the Company elects to purchase all of the Offered Shares, it shall give written notice of such election to the
Participant within such 30-day period. Within 10 days after delivery to the Participant of such notice, the Participant shall tender to the Company at its principal offices the
certificate or certificates representing the Offered Shares, duly endorsed in blank by the Participant or with duly endorsed stock powers attached thereto, all in form suitable for transfer of the
Offered Shares to the Company. Promptly following receipt of such certificate or certificates, the Company shall deliver or mail to the Participant a check in payment of the purchase price for the
Offered Shares; provided that if the terms of payment set forth in the Transfer Notice were other than cash against delivery, the Company may pay for
the Offered Shares on the same terms and conditions as were set forth in 



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the
Transfer Notice; and provided further that any delay in making such payment shall not invalidate the Company's exercise of its option to purchase
the Offered Shares. 


        (c)   If
the Company does not elect to acquire all of the Offered Shares, the Participant may, within the 30-day period following the expiration of the option
granted to the Company under subsection (b) above, transfer the Offered Shares to the proposed transferee, provided that such transfer shall not
be on terms and conditions more favorable to the transferee than those contained in the Transfer Notice. Notwithstanding any of the above, all Offered Shares transferred pursuant to this
Section 5 shall remain subject to this Agreement (including without limitation the restrictions on transfer set forth in Section 4 and the right of first refusal set forth in this
Section 5) and such transferee shall, as a condition to such transfer, deliver to the Company a written instrument confirming that such transferee shall be bound by all of the terms and
conditions of this Agreement. 


        (d)   After
the time at which the Offered Shares are required to be delivered to the Company for transfer to the Company pursuant to subsection (b) above, the Company
shall not pay any dividend to the Participant on account of such Offered Shares or permit the Participant to exercise any of the privileges or rights of a stockholder with respect to such Shares, but
shall, in so far as permitted by law, treat the Company as the owner of such Offered Shares. 


        (e)   The
following transactions shall be exempt from the provisions of this Section 5: 



        (1)   a
transfer of Shares to or for the benefit of any spouse, child or grandchild of the Participant, or to a trust for their benefit; 



        (2)   any
transfer pursuant to an effective registration statement filed by the Company under the Securities Act of 1933, as amended (the "Securities Act"); and 


        (3)   the
sale of all or substantially all of the shares of capital stock of the Company (including pursuant to a merger or consolidation); 



provided, however, that in the case of a transfer pursuant to clause (1) above, such Shares shall remain subject to this Agreement (including
without limitation the restrictions on transfer set forth in Section 4 and the right of first refusal set forth in this Section 5) and such transferee shall, as a condition to such
transfer, deliver to the Company a written instrument confirming that such transferee shall be bound by all of the terms and conditions of this Agreement. 





        (f)    The
Company may assign its rights to purchase Offered Shares in any particular transaction under this Section 5 to one or more persons or entities. 


        (g)   The
provisions of this Section 5 shall terminate upon the earlier of the following events: 



        (1)   the
closing of the sale of shares of Common Stock in an underwritten public offering pursuant to an effective registration statement filed by the Company under the
Securities Act; or 


        (2)   the
sale of all or substantially all of the capital stock, assets or business of the Company, by merger, consolidation, sale of assets or otherwise (other than a merger
or consolidation in which all or substantially all of the individuals and entities who were beneficial owners of the Common Stock immediately prior to such transaction beneficially own, directly or
indirectly, more than 75% of the outstanding securities entitled to vote generally in the election of directors of the resulting, surviving or acquiring corporation in such transaction). 




        (h)   The
Company shall not be required (i) to transfer on its books any of the Shares which shall have been sold or transferred in violation of any of the provisions
set forth in this 



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Agreement,
or (ii) to treat as owner of such Shares or to pay dividends to any transferee to whom any such Shares shall have been so sold or transferred. 




        6.    Agreement in Connection with Public Offering.    The Participant agrees, in connection with the initial
underwritten public offering of the Company's securities pursuant to a registration statement under the Securities Act, (i) not to sell, make short sale of, loan, grant any options for the
purchase of, or otherwise dispose of any shares of Common Stock held by the Participant (other than those shares included in the offering) without the prior written consent of the Company or the
underwriters
managing such initial underwritten public offering of the Company's securities for a period of 180 days from the effective date of such registration statement, and (ii) to execute any
agreement reflecting clause (i) above as may be requested by the Company or the managing underwriters at the time of such initial offering. 


        7.    Escrow.    The Participant shall, upon the execution of this Agreement, execute Joint Escrow Instructions in the
form attached to this Agreement as Exhibit A. The Joint Escrow Instructions shall be delivered to the Secretary of the Company, as escrow agent
thereunder. The Participant shall deliver to such escrow agent a stock assignment duly endorsed in blank and hereby instructs the Company to deliver to such escrow agent, on behalf of the Participant,
the certificate(s) evidencing the Shares issued hereunder. Such materials shall be held by such escrow agent pursuant to the terms of such Joint Escrow Instructions. 


        8.    Restrictive Legends.    All certificates representing Shares shall have affixed thereto legends in substantially
the following form, in addition to any other legends that may be required under federal or state securities laws: 




"The
shares of stock represented by this certificate are subject to restrictions on transfer and an option to purchase set forth in a certain Restricted Stock Agreement between the corporation and the
registered owner of these shares (or his predecessor in interest), and such Agreement is available for inspection without charge at the office of the Secretary of the corporation." 


"The
shares represented by this certificate have not been registered under the Securities Act of 1933, as amended, and may not be sold, transferred or otherwise disposed of in the absence of an
effective registration statement under such Act or an opinion of counsel satisfactory to the corporation to the effect that such registration is not required." 





        9.    Provisions of the Plan.    



        (a)   This
Agreement is subject to the provisions of the Plan, a copy of which is furnished to the Participant with this Agreement. 


        (b)   As
provided in the Plan, upon the occurrence of an Acquisition Event (as defined in the Plan), the repurchase and other rights of the Company hereunder shall inure to
the benefit of the Company's successor and shall apply to the cash, securities or other property which the Common Stock was converted into or exchanged for pursuant to such Acquisition Event in the
same manner and to the same extent as they applied to the Common Stock hereunder. If, in connection with an Acquisition Event, a portion of the cash, securities or other property received upon the
conversion or exchange of the Common Stock subject hereto is to be placed into escrow to secure indemnification or similar obligations, the mix between the vested and unvested portion of such cash,
securities or other property that is placed into escrow shall be the same as the mix between the vested and unvested portion of such securities or other property that is not subject to escrow. 



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        10.    Investment Representations.    The Participant represents, warrants and covenants as follows: 



        (a)   The
Participant is purchasing the Shares for his own account for investment only, and not with a view to, or for sale in connection with, any distribution of the Shares
in violation of the Securities Act, or any rule or regulation under the Securities Act. 



        (b)   The
Participant has had such opportunity as he has deemed adequate to obtain from representatives of the Company such information as is necessary to permit him to
evaluate the merits and risks of his investment in the Company. 


        (c)   The
Participant has sufficient experience in business, financial and investment matters to be able to evaluate the risks involved in the purchase of the Shares and to
make an informed investment decision with respect to such purchase. 


        (d)   The
Participant can afford a complete loss of the value of the Shares and is able to bear the economic risk of holding such Shares for an indefinite period. 



        (e)   The
Participant understands that (i) the Shares have not been registered under the Securities Act and are "restricted securities" within the meaning of
Rule 144 under the Securities Act; (ii) the Shares cannot be sold, transferred or otherwise disposed of unless they are subsequently registered under the Securities Act or an exemption
from registration is then available; (iii) in any event, the exemption from registration under Rule 144 will not be available for at least one year and even then will not be available
unless a public market then exists for the Common Stock, adequate information concerning the Company is then available to the public, and other terms and conditions of Rule 144 are complied
with; and (iv) there is now no registration statement on file with the Securities and Exchange
Commission with respect to any stock of the Company and the Company has no obligation or current intention to register the Shares under the Securities Act. 




        11.    Withholding Taxes; Section 83(b) Election.    



        (a)   The
Participant acknowledges and agrees that the Company has the right to deduct from payments of any kind otherwise due to the Participant any federal, state or local
taxes of any kind required by law to be withheld with respect to the purchase of the Shares by the Participant or the lapse of the Purchase Option. 


        (b)   The
Participant has reviewed with the Participant's own tax advisors the federal, state, local and foreign tax consequences of this investment and the transactions
contemplated by this Agreement. The Participant is relying solely on such advisors and not on any statements or representations of the Company or any of its agents. The Participant understands that
the Participant (and not the Company) shall be responsible for the Participant's own tax liability that may arise as a result of this investment or the transactions contemplated by this Agreement. The
Participant understands that it may be beneficial in many circumstances to elect to be taxed at the time of the Shares are purchased rather than when and as the Company's Purchase Option expires by
filing an election under Section 83(b) of the Code with the IRS within 30 days from the date of purchase. 




        THE
PARTICIPANT ACKNOWLEDGES THAT IT IS THE PARTICIPANT'S SOLE RESPONSIBILITY AND NOT THE COMPANY'S TO FILE TIMELY THE ELECTION UNDER SECTION 83(b), EVEN IF THE PARTICIPANT
REQUESTS THE COMPANY OR ITS REPRESENTATIVES TO MAKE THIS FILING ON THE PARTICIPANT'S BEHALF. 


        12.    No Rights to Employment.    The Participant acknowledges and agrees that the vesting of the shares pursuant to
Section 2 hereof is earned only by continuing service as an employee at the will of the Company (not through the act of being hired or purchasing shares hereunder). The Participant further
acknowledges and agrees that the transactions contemplated hereunder and the vesting schedule 


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set
forth herein do not constitute an express or implied promise of continued engagement as an employee for the vesting period, for any period, or at all. 


        13.    Severability.    The invalidity or unenforceability of any provision of this Agreement shall not affect the
validity or enforceability of any other provision of this Agreement, and each other provision of this Agreement shall be severable and enforceable to the extent permitted by law. 


        14.    Waiver.    Any provision for the benefit of the Company contained in this Agreement may be waived, either
generally or in any particular instance, by the Board of Directors of the Company. 


        15.    Binding Effect.    This Agreement shall be binding upon and inure to the benefit of the Company and the
Participant and their respective heirs, executors, administrators, legal representatives, successors and assigns, subject to the restrictions on transfer set forth in Sections 4 and 5 of this
Agreement. 


        16.    Notice.    All notices required or permitted hereunder shall be in writing and deemed effectively given upon
personal delivery or five days after deposit in the United States Post Office, by registered or certified mail, postage prepaid, addressed to the other party hereto at the address shown beneath his or
its respective signature to this Agreement, or at such other address or addresses as either party shall designate to the other in accordance with this Section 16. 



        17.    Pronouns.    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. 


        18.    Entire Agreement.    This Agreement and the Plan constitutes the entire agreement between the parties, and
supersedes all prior agreements and understandings, relating to the subject matter of this Agreement. 



        19.    Amendment.    This Agreement may be amended or modified only by a written instrument executed by both the
Company and the Participant. 


        20.    Governing Law.    This Agreement shall be construed, interpreted and enforced in accordance with the internal
laws of the State of Delaware without regard to any applicable conflicts of laws. 


        21.    Participant's Acknowledgments.    The Participant acknowledges that he: (a) has read this Agreement;
(b) has been represented in the preparation, negotiation and execution of this Agreement by legal counsel of the Participant's own choice or has voluntarily declined to seek such counsel;
(c) understands the terms and consequences of this Agreement; and (d) is fully aware of the legal and binding effect of this Agreement. 


[Signature
Page to Follow] 


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



	 	 	STARENT NETWORKS, CORP.
	

 	
 	

By:	
 	

 
	 	 	 	 	

	 	 	Name:	 	 
	 	 	Title:	 	 
	 	 	Address:	 	30 International Place

Tewksbury, MA 01876




PARTICIPANT'S ACCEPTANCE  


        The Participant has reviewed the provisions of this Agreement, has had an opportunity to obtain the advice of the Purchaser's own tax and legal advisors prior to
executing this Agreement and fully understands and agrees to the provisions hereof. 


        The
undersigned hereby acknowledges receipt of a copy of the Company's 2000 Stock Incentive Plan. 



	

 	
 	


	 	 	Paul J. Milbury
	 	 	Address:	 	 
	 	 	 	 	

	

 	
 	

 	
 	


	

 	
 	

 	
 	






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   STARENT NETWORKS, CORP.  


Joint Escrow Instructions


February 8,
2007 


Kevin
Newman

Secretary

Starent Networks, Corp.

30 International Place

Tewksbury, MA 01876 


Dear
Sir: 


        As
Escrow Agent for Starent Networks, Corp., a Delaware corporation, and its successors in interest under the Restricted Stock Agreement (the "Agreement") of even date herewith, to which
a copy of these Joint Escrow Instructions is attached (the "Company"), and the undersigned person ("Holder"), you are hereby authorized and directed to hold the documents delivered to you pursuant to
the terms of the Agreement in accordance with the following instructions: 



        1.    Appointment.    Holder irrevocably authorizes the Company to deposit with you any certificates evidencing Shares
(as defined in the Agreement) to be held by you hereunder and any additions and substitutions to said Shares. For purposes of these Joint Escrow Instructions, "Shares" shall be deemed to include any
additional or substitute property. Holder does hereby irrevocably constitute and appoint you as his attorney-in-fact and agent for the term of this escrow to execute with
respect to such Shares all documents necessary or appropriate to make such Shares negotiable and to complete any transaction herein contemplated. Subject to the provisions of this
Section 1 and the terms of the Agreement, Holder shall exercise all rights and privileges of a stockholder of the Company while the Shares are held by you. 


        2.    Closing of Purchase.    


        (a)   Upon
any purchase by the Company of the Shares pursuant to the Agreement, the Company shall give to Holder and you a written notice specifying the number of Shares to be
purchased, the purchase price for the Shares, as determined pursuant to the Agreement, and the time for a closing hereunder (the "Closing") at the principal office of the Company. Holder and the
Company hereby irrevocably authorize and direct you to close the transaction contemplated by such notice in accordance with the terms of said notice. 


        (a)   At
the Closing, you are directed (i) to date the stock assignment form or forms necessary for the transfer of the Shares, (ii) to fill in on such form or
forms the number of Shares being transferred, and (iii) to deliver the same, together with the certificate or certificates evidencing the Shares to be transferred, to the Company against the
simultaneous delivery to you of the purchase price for the Shares being purchased pursuant to the Agreement. 


        3.    Withdrawal.    The Holder shall have the right to withdraw from this escrow any Shares as to which the Purchase
Option (as defined in the Agreement) has terminated or expired. 


        4.    Duties of Escrow Agent.    



        (a)   Your
duties hereunder may be altered, amended, modified or revoked only by a writing signed by all of the parties hereto. 


        (b)   You
shall be obligated only for the performance of such duties as are specifically set forth herein and may rely and shall be protected in relying or refraining from
acting on any instrument reasonably believed by you to be genuine and to have been signed or presented by the proper party or parties. You shall not be personally liable for any act you may do or omit
to do hereunder 



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as
Escrow Agent or as attorney-in-fact of Holder while acting in good faith and in the exercise of your own good judgment, and any act done or omitted by you pursuant to the
advice of your own attorneys shall be conclusive evidence of such good faith. 



        (c)   You
are hereby expressly authorized to disregard any and all warnings given by any of the parties hereto or by any other person or entity, excepting only orders or
process of courts of law, and are hereby expressly authorized to comply with and obey orders, judgments or decrees of any court. If you are uncertain of any actions to be taken or instructions to be
followed, you may refuse to act in the absence of an order, judgment or decrees of a court. In case you obey or comply with any such order, judgment or decree of any court, you shall not be liable to
any of the parties hereto or to any other person or entity, by reason of such compliance, notwithstanding any such order, judgment or decree being subsequently reversed, modified, annulled, set aside,
vacated or found to have been entered without jurisdiction. 


        (d)   You
shall not be liable in any respect on account of the identity, authority or rights of the parties executing or delivering or purporting to execute or deliver the
Agreement or any documents or papers deposited or called for hereunder. 


        (e)   You
shall be entitled to employ such legal counsel and other experts as you may deem necessary properly to advise you in connection with your obligations hereunder and
may rely upon the advice of such counsel. 


        (f)    Your
rights and responsibilities as Escrow Agent hereunder shall terminate if (i) you cease to be Secretary of the Company or (ii) you resign by written
notice to each party. In the event of a termination under clause (i), your successor as Secretary shall become Escrow Agent hereunder; in the event of a termination under clause (ii),
the Company shall appoint a successor Escrow Agent hereunder. 


        (g)   If
you reasonably require other or further instruments in connection with these Joint Escrow Instructions or obligations in respect hereto, the necessary parties hereto
shall join in furnishing such instruments. 


        (h)   It
is understood and agreed that if you believe a dispute has arisen with respect to the delivery and/or ownership or right of possession of the securities held by you
hereunder, you are authorized and directed to retain in your possession without liability to anyone all or any part of said securities until such dispute shall have been settled either by mutual
written agreement of the parties concerned or by a final order, decree or judgment of a court of competent jurisdiction after the time for appeal has expired and no appeal has been perfected, but you
shall be under no duty whatsoever to institute or defend any such proceedings. 


        (i)    These
Joint Escrow Instructions set forth your sole duties with respect to any and all matters pertinent hereto and no implied duties or obligations shall be read into
these Joint Escrow Instructions against you. 


        (j)    The
Company shall indemnify you and hold you harmless against any and all damages, losses, liabilities, costs, and expenses, including attorneys' fees and disbursements,
(including without limitation the fees of counsel retained pursuant to Section 4(e) above, for anything done or omitted to be done by you as Escrow Agent in connection with this Agreement or
the performance of your duties hereunder, except such as shall result from your gross negligence or willful misconduct. 




        5.    Notice.    Any notice required or permitted hereunder shall be given in writing and shall be deemed effectively
given upon personal delivery or upon deposit in the United States Post Office, by registered or certified mail with postage and fees prepaid, addressed to each of the other parties 


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thereunto
entitled at the following addresses, or at such other addresses as a party may designate by ten days' advance written notice to each of the other parties hereto. 



	COMPANY:	 	Starent Networks, Corp.

30 International Place

Tewksbury, MA 01876

Attn: Kevin Newman, Secretary
	

HOLDER:	
 	

Notices to Holder shall be sent to the

address set forth below Holder's signature below.
	

ESCROW AGENT:	
 	

Starent Networks, Corp.

30 International Place

Tewksbury, MA 01876

Attn: Kevin Newman, Secretary






        6.    Miscellaneous.    



        (a)   By
signing these Joint Escrow Instructions, you become a party hereto only for the purpose of said Joint Escrow Instructions, and you do not become a party to the
Agreement. 


        (b)   This
instrument shall be binding upon and inure to the benefit of the parties hereto and their respective successors and permitted assigns. 



	 	 	Very truly yours,
	

 	
 	
STARENT NETWORKS, CORP.
	

 	
 	

By:	
 	

 
	 	 	 	 	

	 	 	Name:
	 	 	Title:
	

 	
 	
HOLDER:
	

 	
 	

 Paul J. Milbury
	

 	
 	

Address:	
 	

 
	 	 	 	 	

	

 	
 	


	

 	
 	

Date Signed:	
 	

 
	 	 	 	 	

	
ESCROW AGENT:	
 	

 	
 	

 
	

 Kevin Newman	
 	

 	
 	

 




A-3








Exhibit B  


STOCK POWER  


        FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers
unto                        
(                        ) shares of Common Stock, par value $0.001 per
share, of Starent Networks, Corp., a Delaware corporation, and does hereby irrevocably constitute and appoint the Secretary of Starent Networks, Corp. as its Attorney to transfer said shares on the
books of said corporation with full power of substitution in the premises. 



	Dated:	 	 	 	Signature:
	 	 	
	 	 
	

 	
 	

 	
 	

 Name













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