**EXHIBIT 10.16**

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# **SECURITYAGREEMENT**

For valuereceived, and in consideration of one or more loans, letters of credit or otherfinancial accommodations extended by **JPMorgan Chase Bank, N.A.**or any of its subsidiaries or affiliates (the “Bank”), to **Avistar CommunicationsCorporation**, a Delaware corporation (the “Grantor”), the Grantor andthe Bank agree as follows:

**1.             Definitions.**

“Collateral” meansall personal property of the Grantor whether presently existing or hereaftercreated or acquired, and wherever located, including but not limited to:(i) accounts (including health-care-insurance receivables), chattel paper,deposit accounts, documents (including negotiable documents), equipment,general intangibles, goods (including fixtures), instruments (includingpromissory notes), inventory (including all goods held for sale or lease or tobe furnished under a contract of service, and including returns andrepossessions), investment property (including securities and securitiesentitlements), letter of credit rights, money, and all of Grantor’s books andrecords with respect to any of the foregoing, and the computers and equipmentcontaining said books and records; (ii) all claims, demands, causes and choses in action in respect of anyof the foregoing and all all accessions and additions thereto; and (iii) any and all cash and non-cashproceeds and products of any of the foregoing, including without limitation,any and all proceeds of any insurance, indemnity, instruments, warranty orguaranty payable to such Grantor from time to time with respect to theCollateral and any and all other amounts from time to time paid or payableunder or in connection with any of the Collateral.

“Default” shallmean each “Event of Default” (as defined in the Note).

“Liabilities” meansindebtedness, obligations and liabilities of any kind of the Grantor to theBank, now or in the future, absolute or contingent, direct or indirect, jointor several, due or not due, arising by operation of law or otherwise, and costsand expenses incurred by the Bank in connection with the Collateral, thisAgreement or any Liability Document.

“LiabilityDocument” means any instrument, agreement or document evidencing or deliveredin connection with the Liabilities (including, without limitation, the Note), as amended from time totime.

“Loan” shall havethe meaning given such term in the Note.

“Note” means the Revolving PromissoryNote (Libor/Prime) dated as of December 23, 2006 by the Grantor in favorof the Bank in the maximum principal amount of $10,000,000, as amended fromtime to time.

“UCC” means theUniform Commercial Code in effect in the State of New York.  Unless the context otherwise requires, allterms used in this Agreement which are defined in the UCC will have themeanings stated in the UCC.

**2.             Grantof Security Interest. **Assecurity for the payment of all the Liabilities, the Grantor pledges, transfersand assigns to the Bank and grants to the Bank a security interest in and rightof setoff against, the Collateral.

**3.             Agreements,Representations and Warranties of the Grantor and Rights of the Bank.**

(a)           The Grantor represents and warrantsthat:****the Grantor is the sole owner of theCollateral and the Collateral is free of all encumbrances except for thesecurity interest in favor of the Bank created by this Agreement

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(b)           The Grantor irrevocably authorizesthe Bank to exercise the rights granted to the Bank herein, at its option, forits own benefit, either in its own name or in the name of the Grantor, andappoints the Bank as its attorney-in-fact to take all action permitted underthis Agreement.

(c)           Without the prior written consent ofthe Bank, the Grantor agrees not to sell, assign, transfer, exchange, orotherwise dispose of, or grant any option with respect to, any Collateral(other than sales of inventory and any grants of non-exclusive licenses orsimilar arrangements for the use of property of the Borrower, in each case inthe ordinary course of business and consistent with past practice), nor willthe Grantor create, incur or permit to exist any pledge, lien, mortgage,hypothecation, security interest, encumbrance, option or any other charge withrespect to any of the Collateral, or any interest therein, or any proceedsthereof, except for the lien and security interest provided for by thisAgreement or as otherwise provided in any other Liability Document.

(d)           The Grantor will not changejurisdiction of its incorporation or organization (by migratory merger orotherwise) except upon 30 days’ prior written notice to the Bank.

(e)           The Bank may, in its name, or in thename of the Grantor:  (i) execute andfile financing statements under the UCC or any other filings or noticesnecessary or desirable to create, perfect or preserve its security interest,all without notice (except as required by applicable law and not waivable) andwithout liability except to account for property actually received by it; (ii)demand, sue for, collect or receive any money or property at any time payableor receivable on account of or in exchange for, or make any compromise orsettlement deemed desirable with respect to, any item of the Collateral  (but shall be under no obligation to do so);(iii) make any notification (to the issuer of any certificate or security,or otherwise, or take any other action in connection with the perfection orpreservation of its security interest  orany enforcement of remedies, and retain any documents evidencing the title ofthe Grantor to any item of the Collateral; and (iv) issue entitlement orderswith respect to any of the Collateral.

The Grantor agreesthat it will not file or permit to be filed any termination statement withrespect to the Collateral or any financing or like statement with respect tothe Collateral in which the Bank is not named as the sole secured party or otherwisedispose of, grant any option with respect to, or pledge, or otherwise encumberthe Collateral.  At the request of theBank the Grantor agrees to do all other things which the Bank may deemnecessary or advisable in order to perfect and preserve its security interest,perfection and operational control and to give effect to the rights granted tothe Bank under this Agreement or enable the Bank to comply with any applicablelaws or regulations.  Notwithstanding theforegoing, the Bank does not assume any duty with respect to the Collateral andis not required to take any action to collect, preserve or protect its or theGrantor’s rights in any item of the Collateral. The Grantor releases the Bank and agrees to hold the Bank harmless fromany claims, causes of action and demands at any time arising with respect tothis Agreement, the use or disposition of any item of the Collateral or anyaction taken or omitted to be taken by the Bank with respect thereto.

**4.             Currency Conversion. **For calculation purposes, any currency in which the Collateral isdenominated (the “Collateral Currency”) will be converted into the currency ofthe Liabilities (the “Liability Currency”) at the spot rate of exchange for thepurchase of the Liability Currency with the Collateral Currency quoted by theBank at such place as the Bank deems appropriate (or, if no such rate is quotedon any relevant date, estimated by the Bank on the basis of the Bank’s lastquoted spot rate) or another prevailing rate that the Bank deems more appropriate.

**5.             Remedies.**

On a Default, the Bank will havethe rights and remedies under the UCC and the other rights granted to the Bankunder this Agreement and may exercise its rights without regard to any premiumor penalty from liquidation of any Collateral and without regard to the Grantor’sbasis or holding period for any Collateral.

The Bank may sell in the Boroughof Manhattan, New York City, or elsewhere, in one or more sales or parcels, atthe price as the Bank deems best, for cash or on credit or for other property,for immediate or future delivery, any item of the Collateral, at any broker’sboard or at public or private sale, in any reasonable manner permissible underthe UCC (except that, to the extent permissible under the UCC, the Grantor waivesany requirements of the UCC) and the Bank or anyone else may be the purchaserof the Collateral and hold it free from any claim or right including, withoutlimitation, any equity of redemption of the Grantor, which right the Grantorexpressly waives.

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The Bank may also, in its solediscretion: (i) convert any part of the Collateral Currency into the LiabilityCurrency;  (ii) hold any monies orproceeds representing the Collateral in a cash collateral account in theLiability Currency or other currency that the Bank reasonably selects; (iii)invest such monies or proceeds on behalf of the Grantor; and (iv) apply anyportion of the Collateral, first, to all costs and expenses of the Bank,second, to the payment of interest on the Liabilities and any fees orcommissions to which the Bank may be entitled, third, to the payment ofprincipal of the Liabilities, whether or not then due, and fourth, to theGrantor.

The Grantor will pay to the Bankall expenses (including attorneys’ fees and legal expenses incurred by the Bankand the allocated costs of its in-house counsel) in connection with theexercise of any of the Bank’s rights or obligations under this Agreement or theLiability Documents.  The Grantor willtake any action requested by the Bank to allow it to sell or dispose of theCollateral.  Notwithstanding that theBank may continue to hold Collateral and regardless of the value of theCollateral, the applicable Liability Party will remain liable for the paymentin full of any unpaid  balance of theLiabilities.

**6.             Jurisdiction.**

Tothe maximum extent not prohibited by applicable law, the Grantor herebyirrevocably: (i) submits to the jurisdiction of any New York state or UnitedStates federal court sitting in New York City over any action or proceedingarising out of this Agreement;(ii) agrees that all claims in respect of suchaction or proceeding may be held and determined in such New York state orfederal court;  (iii) agrees thatany action or proceeding brought against the Bank may be brought only in a NewYork state or United States federal court sitting in New York county;  (iv)consents to the service of process in any such action or proceeding in eitherof said courts by mailing thereof by the Bank by registered or certified mail,postage prepaid, to the Grantor at its address specified on the signature pagehereof, or at the Grantor’s most recent mailing address as set forth in therecords of the Bank; and (v) waives any defense on the basis of inconvenientforum.

The Grantor agrees that afinal judgment in any such action or proceeding shall be conclusive and may beenforced in any other jurisdiction by suit or proceeding in such state.  Nothing herein shall affect the right of theBank to serve legal process in any other manner permitted by law or affect theright of the Bank to bring any action or proceeding against the Grantor or itsproperty in the courts of any other jurisdiction.

**7.             Waiver of Jury Trial**.  THEUNDERSIGNED AND THE BANK EACH WAIVE ANY RIGHT TO JURY TRIAL.

**8.             Notices. **Unless otherwiseagreed in writing, notices may be given to the Bank and the Grantor at theirtelecopier numbers (confirmed by telephone to their telephone numbers) oraddresses listed on the signature page of this Agreement, or such othertelecopier (and telephone) number or addresses communicated in writing byeither party to the other.  Notices tothe Bank are effective on receipt.

**9.             Miscellaneous.**

(a)           This Agreement shall be binding onthe Grantor and its successors and assigns and shall inure to the benefit ofthe Bank and its successors and assigns, except that the Grantor may notdelegate any of its obligations hereunder without the prior written consent ofthe Bank.

(b)           No amendment or waiver of anyprovision of this Agreement nor consent to any departure by the Grantor will beeffective unless it is in writing and signed by the Grantor and the Bank andwill be effective only in that specific instance and for that specificpurpose.  No failure on the part of theBank to exercise, and no delay in exercising, any right will operate as awaiver or preclude any other or further exercise or the exercise of any otherright.

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(c)           Therights and remedies in this Agreement are cumulative and not exclusive of anyrights and remedies which the Bank may have under law or under other agreementsor arrangements with the Grantor or any Liability Party.

(d)           Theprovisions of this Agreement are intended to be severable.  If for any reason any provision of thisAgreement is not valid or enforceable in whole or in part in any jurisdiction,that provision will, as to that jurisdiction, be ineffective to the extent ofthat invalidity or unenforceability without in any manner affecting thevalidity or enforceability in any other jurisdiction or the remainingprovisions of this Agreement.

(e)           TheGrantor hereby waives presentment, notice of dishonor and protest of allinstruments included in or evidencing the Liabilities or the Collateral and anyother notices and demands, whether or not relating to those instruments.

(f)            ThisAgreement is governed by and construed according to the law of the State of NewYork, without regard to the conflict of laws principles, and with the laws ofthe United States of America as applicable.

(g)           ThisAgreement may be executed in any number of counterparts, all of which takentogether shall constitute one and the same instrument.

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IN WITNESS WHEREOF, the Grantor has signed thisAgreement as of December 22, 2006.
| ACCEPTED:                                                                                                                                                     |                                  |   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------|--------|
|                                                                                                                                                          |                                  |   |
|                                                                                                                                                          |                                  |   |
| JPMorgan Chase  Bank, N.A.                                                                                                                                    |                                  |   |
|                                                                                                                                                          |                                  |   |   |
|                                                                                                                                                          |                                  |   |   |
| By:                                                                                                                                                           |  J.P. Morgan Trust Company, N.A. |   |   |
|                                                                                                                                                          |                                  |   |   |
| By:                                                                                                                                                           | /s/ Nancy A.  Sheppard                |   |   |
|                                                                                                                                                          | Name: Nancy A.  Sheppard              |   |   |
|                                                                                                                                                          | Title:  Managing Director        |   |   |
|                                                                                                                                                          |                                  |   |   |
|                                                                                                                                                          |                                  |   |   |
|                                                                                                                                                          |                                  |   |   |
| **Address for notices to the Bank:**                                                                                                                          |                                  |   |
|                                                                                                                                                          |                                  |   |   |
|                                                                                                                                                          |                                  |   |   |
| JPMorgan Chase Bank, N.A.  Private Bank Credit  Attn:** **Patricia DeLeo  345 Park Avenue, Floor 04  New York, NY 10154-0004                             |                                  |
|                                                                                                                                                          |                                  |
| With a courtesy copy to                                                                                                                                       |                                  |
|                                                                                                                                                          |                                  |
| JPMorgan Chase Bank, N.A.  Attn:  Nancy A. Sheppard560 Mission Street, 12th floor  San Francisco, CA 94105                                               |                                  |
|                                                                                                                                                          |                                  |   |   |
|                                                                                                                                                          |                                  |   |   |
| **Avistar  Communications Corporation**                                                                                                                       |                                  |   |
| ** **                                                                                                                                                    |                                  |   |
|                                                                                                                                                          |                                  |   |   |
| By:                                                                                                                                                           | /s/Robert J.  Habig                   |   |   |
|                                                                                                                                                          | Name: Robert J.  Habig                |   |   |
|                                                                                                                                                          | Title: Chief  Financial Officer       |   |   |
|                                                                                                                                                          |                                  |   |   |
|                                                                                                                                                          |                                  |   |   |
| By:                                                                                                                                                           |                                  |   |   |
|                                                                                                                                                          | Name:                                 |   |   |
|                                                                                                                                                          | Title:                                |   |   |
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| **Address  for Notices to the Grantor:**                                                                                                                      |                                  |   |
|                                                                                                                                                          |                                  |   |   |
|                                                                                                                                                          |                                  |   |   |
| Attn:  Robert Habig  555 Twin Dolphin Drive  3rd Floor  Redwood Shores, CA 94065  Telecopier:  (650) 610-2505  Telephone:  (650) 610-2910 |                                  |   |
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| State of  | ** ** |   ) |          |   |
|-----------|------------|---------------|---------------|--------|
|      | ** ** | ** **    |   ) | ss.:   |   |
| County of | ** ** |   ) |          |   |

 

On the ____ day ofDecember in the year 2006, before me, the Grantor, personally appeared **_____________________________**,personally known to me or proved to me on the basis of satisfactory evidence tobe the individual whose name is subscribed to the within instrument andacknowledged to me that he/she executed the same in his/her capacity, and thatby his/her signature on the instrument, the individual, or the person uponbehalf of which the individual acted, executed the instrument.
|            | ** ** | ** ** | ** ** |   |          |
|------------|------------|------------|------------|--------|---------------|
| ** ** | ** ** | ** ** | ** ** |   | Notary Public |

 
| State of  | ** ** |   ) |          |   |
|-----------|------------|---------------|---------------|--------|
|      | ** ** | ** **    |   ) | ss.:   |   |
| County of | ** ** |   ) |          |   |

 

On the ____ day ofDecember in the year 2006, before me, the Grantor, personally appeared **_____________________________**,personally known to me or proved to me on the basis of satisfactory evidence tobe the individual whose name is subscribed to the within instrument andacknowledged to me that he/she executed the same in his/her capacity, and thatby his/her signature on the instrument, the individual, or the person uponbehalf of which the individual acted, executed the instrument.
|            | ** ** | ** ** | ** ** |   |          |
|------------|------------|------------|------------|--------|---------------|
| ** ** | ** ** | ** ** | ** ** |   | Notary Public |

 

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