Exh. 10.9.5

FOURTH AMENDMENT  TO  LOAN AND SECURITY AGREEMENT

This Fourth Amendment to the Loan and Security Agreement (the "Amendment") is entered into as of February 27, 2004, by and between COMERICA BANK ("Bank")
and AVISTAR COMMUNICATIONS CORPORATION ("Borrower").

RECITALS

Borrower and Bank are parties to that certain Loan and Security Agreement dated as of February 27, 2002, (as amended from time to time, including without
limitation that certain First Amendment to Loan and Security Agreement dated December 16, 2002, Second Amendment to Loan and Security Agreement dated March 10, 2003, and Third Amendment
to Loan and Security Agreement dated July 2, 2003, together with any related agreements, the "Agreement"). Hereinafter, all indebtedness owing by Borrower to Bank shall be referred to as the
"Indebtedness." The parties desire to amend the Agreement in accordance with the terms of this Amendment.

NOW,
THEREFORE, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties agree as follows:

AGREEMENT









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IN
WITNESS WHEREOF, the undersigned have executed this Amendment as of the first date above written.

| |  | AVISTAR COMMUNICATIONS CORPORATION
| |  | ----------------------------------
| |  | By:                               
| |  | Title:                            
| |  | COMERICA BANK                     
| |  | By:                               
| |  | Title:                            

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EXHIBIT D    COMPLIANCE CERTIFICATE

|TO:   |  | COMERICA BANK                     
|----- |  | ----------------------------------
|FROM: |  | AVISTAR COMMUNICATIONS CORPORATION

The
undersigned authorized officer of AVISTAR COMMUNICATIONS CORPORATION hereby certifies that in accordance with the terms and conditions of the Loan and Security Agreement between
Borrower and Bank (as amended, the "Agreement"), (i) Borrower is in complete compliance for the period
ending                        with all required covenants except as noted below and
(ii) all representations and warranties of Borrower stated in the Agreement are true and correct as of the date hereof, except those representations and warranties expressly referring to
another date shall be true, correct and complete in all material respects as of such date. Attached herewith are the required documents supporting the above certification. The Officer further
certifies that these are prepared in accordance with Generally Accepted Accounting Principles (GAAP) (except for the absence of footnotes and subject to normal year end adjustments) and are
consistently applied from one period to the next except as explained in an accompanying letter or footnotes.

Please indicate compliance status by circling Yes/No under "Complies" column.

|Reporting Covenant                           |  | Required                                               |  | Complies
|-------------------------------------------- |  | ------------------------------------------------------ |  | --------
|Monthly consolidated financial statements    |  | Monthly within 30 days (or quarterly if no borrowings) |  | Yes     
|10K and 10Q                                  |  | 10 days of SEC filing date                             |  | Yes     
|Quarterly consolidating financial statements |  | Quarterly within 30 days                               |  | Yes     
|A/R & A/P Agings                             |  | Monthly within 15 days if borrowing                    |  | Yes     
|A/R Audit                                    |  | Initial and Semi-Annual                                |  | Yes     

|Financial Covenant  |                              | Required |          | Actual |       | Complies
|------------------- | ---------------------------- | -------- | -------- | ------ | ----- | --------
|On a monthly basis: |                              |          |          |        |       |         
|                    | Minimum Adjusted Quick Ratio |          | .75:1.00 |        | :1.00 |         
|                    | Loan to Value Ratio          |          | 50%      |        | %     |         

|Comments Regarding Exceptions:See Attached.
|-------------------------------------------
|                                           
|                                           
|Sincerely,                                 
|                                           
|SIGNATURE                                  
|TITLE                                      
|                                           
|DATE                                       

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