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                                                                     EXHIBIT 4.6

                         WAIVER OF ANTI-DILUTION RIGHTS
              SERIES A PREFERRED STOCK AND SERIES B PREFERRED STOCK

         This WAIVER OF ANTI-DILUTION RIGHTS FOR SERIES A PREFERRED STOCK AND
SERIES B PREFERRED STOCK ("Waiver") is entered into as of this 30th day of March
2001 by and among USDATA Corporation, a Delaware corporation (the
"Corporation"), Safeguard Delaware, Inc., a Delaware corporation ("Safeguard
Delaware"), Safeguard 2000 Capital, L.P., a Delaware limited partnership
("Safeguard 2000") and SCP Private Equity Partners II, L.P., a Delaware limited
partnership ("SCP").

                                    RECITALS

         WHEREAS, Safeguard Delaware and Safeguard 2000 (the "Preferred Stock
Holders") hold shares of Series A Preferred Stock, par value $0.01 per share
(the "Series A Preferred Stock") or Series B Preferred Stock, par value $0.01
per share (the "Series B Preferred Stock") of the Corporation;

         WHEREAS, Section 6(c) of the Corporation's Certificate of Designation
for Series A Preferred Stock and Series B Preferred Stock (the "Series A and B
Designation") provides for certain adjustments to the conversion prices of the
Series A Preferred Stock and Series B Preferred Stock upon certain issuances of
stock or warrants by the Corporation (the "Anti-Dilution Rights");

         WHEREAS, the Corporation plans to issue and sell up to 75,000 shares of
the Parent's Series C-1 Preferred Stock, par value $0.01 per share ("Series C-1
Stock"), to SCP at a purchase price of $40.00 per share and to issue to SCP a
warrant (the "Warrant") to purchase 75,000 shares of Series C-2 Preferred Stock,
par value $0.01 per share ("Series C-2 Stock") pursuant to the Series C
Preferred Stock Purchase Agreement (the "Purchase Agreement");

         WHEREAS, the Corporation plans to reserve shares of Series C-1 Stock
and Series C-2 Stock, issuable as cumulative dividends under the Corporation's
Certificate of Designation for Series C-1 Preferred Stock and Series C-2
Preferred Stock (the "PIK Shares");

         WHEREAS, in order to induce SCP to enter into the Purchase Agreement
and to consummate the transactions contemplated thereby, the Preferred Stock
Holders now desire to provide for the waiver of their Anti-Dilution Rights with
respect to their shares of the Series A Preferred Stock and the Series B
Preferred Stock;

                                     WAIVER

         NOW THEREFORE, in consideration of the foregoing and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto, each intending to be legally bound hereby,
agree as follows:


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1. The Preferred Stock Holders hereby waive their rights to any adjustment to
   the conversion price of their shares of Series A Preferred Stock and Series B
   Preferred Stock under Section 6(c) of the Series A and B Designation arising
   from the issuance of the Series C-1 Stock, the Series C-2 Stock, the Warrant,
   the Warrant Shares and the PIK Shares.

2. The construction, validity and interpretation of this Waiver will be governed
   by the internal laws of the State of Delaware without giving effect to any
   choice of law or conflict of law provision or rule (whether of the State of
   Delaware or any other jurisdiction) that would cause the application of the
   laws of any jurisdiction other than the State of Delaware.

3. This Waiver may be executed in two or more counterparts, each of which shall
   be deemed an original, but all of which together shall constitute one and the
   same instrument.

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         IN WITNESS WHEREOF, the parties have executed this WAIVER OF
ANTI-DILUTION RIGHTS FOR SERIES A PREFERRED STOCK AND SERIES B PREFERRED STOCK
as of the date first above written.

                            USDATA CORPORATION

                            By:
                                --------------------------------------------
                                Robert Merry
                                Chief Executive Officer

                            SAFEGUARD DELAWARE, INC.

                            By:
                                --------------------------------------------
                            Name:
                                  ------------------------------------------
                            Title:
                                   -----------------------------------------


                            SAFEGUARD 2000 CAPITAL, L.P.

                            By: Safeguard Delaware, Inc.,
                                its General Partner

                            By:
                                --------------------------------------------
                            Name:
                                  ------------------------------------------
                            Title:
                                   -----------------------------------------


                            SCP PRIVATE EQUITY PARTNERS II, L.P.

                            By: SCP Private Equity II General Partner, L.P.,
                                its General Partner

                            By: SCP Private Equity II LLC,
                                its Manager

                            By:
                                --------------------------------------------
                            Name:
                                  ------------------------------------------
                            Title:
                                   -----------------------------------------



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