UNITED STATES
SECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549

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FORM 10-K/A
Amendment No. 1

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|ý                                                         | ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934    
|--------------------------------------------------------- | ----------------------------------------------------------------------------------------
|For the fiscal year ended December 31, 2003              
|OR                                                       
|o                                                         | TRANSITION REPORT PURSUANT TO SECTION 13 OF 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|For the transition period
from            to            .

Commission File Number: 000-31121

AVISTAR COMMUNICATIONS CORPORATION(Exact name of registrant as specified in its charter)

|Delaware(State or other jurisdiction
of incorporation or organization)                               | 88-0463156(I.R.S. Employer
Identification Number)
|---------------------------------------------------------------------------------------------------- | -------------------------------------------------
|555 Twin Dolphin Drive, Suite 360
Redwood Shores, California(Address of Principal Executive Offices) | 94065(Zip Code)                                  

Registrant's telephone number, including area code: (650) 610-2900

Securities registered pursuant to Section 12(b) of the Act:

|Title of each class |  | Name of each exchange on which registered
|------------------- |  | -----------------------------------------
|None                |  | None                                     

Securities registered pursuant to Section 12(g) of the Act:
Common Stock, $0.001 par value

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past
90 days. Yes  ý    No  o

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be
contained, to the best of the registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment
to this Form 10-K. ý

Indicate by check mark whether the registrant is an accelerated filer (as defined in Rule 12b-2 of the
Act). Yes  o    No  ý

Aggregate market value of the voting and non-voting common equity held by non-affiliates computed by reference to the price at which the
common equity was last sold on June 30, 2003 was $4,656,141. Shares of Common Stock held by each executive officer and director and by each person who owns 5% or more of the outstanding Common
Stock have been excluded in that such persons may be deemed to be affiliates. This determination of affiliate status is not necessarily a conclusive determination for other purposes.

As
of December 31, 2003, the registrant had outstanding 30,210,758 shares of Common Stock.

DOCUMENTS INCORPORATED BY REFERENCE

The Registrant has incorporated by reference into Part III of this Annual Report on Form 10-K specific portions of its Proxy Statement
for its 2004 Annual Meeting of Stockholders.



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EXPLANATORY NOTE

This Annual Report on Form 10-K/A ("Form 10-K/A") is being filed as Amendment No. 1 to the Registrant's Annual Report
on Form 10-K for the fiscal year ended December 31, 2003 ("Form 10-K"). This Form 10-K/A is filed with the Securities and Exchange
Commission (the "Commission") solely for the purpose of re-filing Exhibit 31.1Rule 13a-14(a)/15d-14(a) Certification by the Chief
Executive Officer and Exhibit 31.2Rule 13a-14(a)/15d-14(a) Certification by the Chief Financial Officer. These exhibits are being
re-filed solely for the purpose of removing an extra certification included in such exhibits as previously filed, which extra certification is not required by
Rule 13a-14(a) or 15d-14(a). This Form 10-K/A does not otherwise change or update the disclosures set forth in the Form 10-K as
originally filed and does not otherwise reflect events occurring after the original filing of the Form 10-K.

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PART IV

ITEM 15. EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K

Exhibit 31.1
filed with the original Form 10-K is replaced in its entirety by Exhibit 31.1 filed with this Form 10-K/A.
Exhibit 31.2 filed with the original Form 10-K is replaced in its entirety by Exhibit 31.2 filed with this Form 10-K/A.

|Exhibit Number |  | Description                                                                                                                                                                     
|-------------- |  | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|               |  |                                                                                                                                                                                 
|31.1           |  | Rule 13a-14(a)/15d-14(a) Certification by the Chief Executive Officer                                                                                                           
|31.2           |  | Rule 13a-14(a)/15d-14(a) Certification by the Chief Financial Officer                                                                                                           
|32             |  | Certification by the Chief Executive Officer and Chief Financial Officer pursuant to 18 U.S.C Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report on
Form 10-K/A to be signed on its behalf by the undersigned, thereunto duly authorized.

| | AVISTAR COMMUNICATIONS CORPORATION
| | ----------------------------------
| | By:                               

Date:
March 26, 2004

Pursuant
to the requirements of the Securities Exchange Act of 1934, as amended, this report on Form 10-K/A has been signed below by the following persons on behalf of
the registrant and in the capacities and on the dates indicated:

|Signature                                             |  | Title                                                                |  | Date          
|----------------------------------------------------- |  | -------------------------------------------------------------------- |  | --------------
|                                                      |  |                                                                      |  |               
|/s/GERALD J. BURNETTGerald J. Burnett                 |  | Chief Executive Officer and Chairman
(Principal Executive Officer)   |  | March 26, 2004
|/s/ROBERT J. HABIGRobert J. Habig                     |  | Chief Financial Officer
(Principal Financial and Accounting Officer) |  | March 26, 2004
|/s/WILLIAM L. CAMPBELL*William L. Campbell            |  | Executive Vice President and Director                                |  | March 26, 2004
|/s/R. STEPHEN HEINRICHS*R. Stephen Heinrichs          |  | Director                                                             |  | March 26, 2004
|/s/ROBERT P. LATTA*Robert P. Latta                    |  | Director                                                             |  | March 26, 2004
|/s/ROBERT M. METCALFE*Robert M. Metcalfe              |  | Director                                                             |  | March 26, 2004
|/s/DAVID M. SOLO*David M. Solo                        |  | Director                                                             |  | March 26, 2004
|*/s/ROBERT J. HABIG(Robert J. HabigAttorney in Fact) |  | Attorney in Fact                                                     |  | March 26, 2004

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INDEX TO EXHIBITS

|Exhibits |  |                                                                                                                                                                                 
|-------- |  | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|         |  |                                                                                                                                                                                 
|31.1     |  | Rule 13a-14(a)/15d-14(a) Certification by the Chief Executive Officer                                                                                                           
|31.2     |  | Rule 13a-14(a)/15d-14(a) Certification by the Chief Financial Officer                                                                                                           
|32       |  | Certification by the Chief Executive Officer and Chief Financial Officer pursuant to 18 U.S.C Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

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