EXHIBIT 10.10

[Dow Jones Logo]                                       Dow Jones Markets
                                                       200 Liberty Street
                                                       New York, New York 10281

                                October 27, 1997

Omega Research, Inc.
8700 West Flagler Street
Suite 250
Miami, Florida 33174-2428

         Re:   MODIFICATIONS TO SOFTWARE LICENSE, MAINTENANCE AND DEVELOPMENT
               AGREEMENT DATED MARCH 12, 1997 (THE "SUPERCHARTS AGREEMENT")
               BETWEEN DOW JONES MARKETS, INC. ("TELERATE") AND OMEGA RESEARCH,
               INC. ("OMEGA"), AND MODIFICATION TO SOFTWARE LICENSE, MAINTENANCE
               AND DEVELOPMENT AGREEMENT DATED AUGUST 26, 1994, AS AMENDED BY
               FIRST AMENDMENT TO SOFTWARE LICENSE, MAINTENANCE AND
               DEVELOPMENT AGREEMENT DATED MARCH 7, 1997 (THE "TRADESTATION
               AGREEMENT") BETWEEN TELERATE AND OMEGA

Ladies and Gentlemen:

         Reference is made to the SuperCharts Agreement and the TradeStation
Agreement. This letter shall serve to (a) modify certain provisions of the
SuperCharts Agreement and (b) add one subsection to the TradeStation Agreement.
Capitalized terms used herein, which are not otherwise defined herein, shall
have the respective meanings ascribed to them in the SuperCharts Agreement.

         The parties agree as follows:

         1. SUPERCHARTS AGREEMENT.

                  (a) Notwithstanding anything to the contrary contained in the
SuperCharts Agreement, Telerate shall have the right, but not the obligation, to
include the Telerate Version of SuperCharts Special Edition in Workstations and
Stand-Alone Units that Telerate, its Affiliates and Independent Distributors
distribute to existing Telerate customers and to future customers such as those
Telerate currently serves. To the extent that Telerate exercises this right,
which it may exercise during the term of this Agreement from time to time and in
whole or in part in Telerate's sole and absolute discretion, all other
provisions of the SuperCharts Agreement relating to, or affecting, the exercise
of such right shall continue to apply, including but not limited to Telerate's
obligation to include the Telerate Version of SuperCharts Special Edition only
on a completely royalty-free basis to the subscriber, customer or end-user and
only in Workstations and Stand-Alone Units. Nothing


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herein shall be deemed to have enlarged or expanded in any manner the license
granted to Telerate in the SuperCharts Agreement concerning the Telerate Version
of SuperCharts Special Edition.

                  (b) Notwithstanding anything to the contrary contained in the
SuperCharts Agreement, including but not limited to Section E. 1(a), there shall
be no standard which Telerate shall be required to observe in connection with
its marketing efforts regarding the Telerate Version of SuperCharts Products.
Accordingly, Section E. l(a) is hereby amended in its entirety to read as
follows:

                      "Telerate shall have complete control over, and discretion
in determining the manner of promoting, marketing, selling and/or sublicensing
the Telerate Version of SuperCharts Products."

                  (c) Section 3 of the SuperCharts Agreement is hereby deleted
and is void and of no further force or effect. The Non-Competition Agreement,
dated March 12, 1997 between William Cruz and Ralph Cruz and Telerate is hereby
cancelled and of no further force or effect. It is expressly understood that the
Non-Competition Covenant (as defined in the March 7, 1997 First Amendment to the
TradeStation Agreement) will remain in full force and effect. Nothing contained
in this letter, including this paragraph (c), will in any way be deemed to be a
waiver by Telerate of its assertion that each of the SuperCharts Products is
subject to the Non-Competition Covenant in the TradeStation Agreement (including
as such Non-Competition Covenant is described in Section 1(a) of the March 7,
1997 First Amendment to the TradeStation Agreement). Telerate acknowledges that
Omega has informed it that Omega disputes Telerate's position on this issue.

                  (d) The parties acknowledge and confirm that the Telerate
Version of SuperCharts Products has been Accepted. The parties shall continue to
address in good faith and in a manner consistent with past practices any
existing "bugs" which may exist in the Telerate Version of SuperCharts Products.

                  (e) Except as set forth above, the SuperCharts Agreement
remains unmodified and of full force and effect.

         2. TRADESTATION AGREEMENT.

                  (a) The TradeStation Agreement is hereby amended by adding to
Section E thereof a subsection 4 which reads as follows (with capitalized terms
used therein having the respective meanings ascribed to them in the TradeStation
Agreement):

                      "4. TRADESTATION SLIDE SHOW DEMO. Effective as soon as
practicable after the date hereof but in no event later than the date on which
the next major version of the Dow Jones Workstation Platform is commercially
released (which is anticipated to occur in January 1998), and continuing
throughout the term of this Agreement, Telerate shall have the obligation to
include in the Dow Jones Workstation Platform (and any upgrades or new releases
thereof), and to distribute (and cause its Affiliates and Independent
Distributors to distribute) to all existing Telerate customers and to future
customers such as those Telerate currently serves to which the Dow Jones
Workstation


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Platform (or any upgrade or new release) is licensed, sold or distributed, as
part thereof, on a completely royalty-free basis to the subscriber, customer or
other end-user, an icon in the Workstation Desktop Manager (which is displayed
on the user's screen after logging in) that runs the TradeStation Slide Show
Demo (as defined below). Telerate's obligation to distribute the TradeStation
Slide Show Demo to existing Dow Jones Workstation subscribers relates only to
upgrades and new releases thereof. "TradeStation Slide Show Demo" shall mean a
slide-show demonstration of the Telerate Version of TradeStation which can be
accessed and displayed by a Workstation computer and which is mutually approved
by both parties in writing, such approval not to be unreasonably withheld. The
parties will cooperate to develop and implement the TradeStation Slide Show Demo
as soon as practicable. Omega hereby grants to Telerate a license to use the
TradeStation Slide Show Demo solely for the purposes and in the manner set forth
in this subsection, and for no other purpose and in no other manner whatsoever.
As between Omega and Telerate, solely Omega owns all right, title and interest
in and to the TradeStation Slide Show Demo.

                  (b) Except as set forth in the preceding subparagraph (a), the
TradeStation Agreement remains unmodified and of full force and effect.

         Please indicate your acceptance of, and agreement to, all of the
foregoing by countersigning this letter in the space provided below for that
purpose.

                                                     Very truly yours,

                                            DOW JONES MARKETS, INC.

                                            By: /s/ JULIAN B. CHILDS
                                                ------------------------
                                                Julian B. Childs
                                                Executive Vice President

AGREED TO AND ACCEPTED:

OMEGA RESEARCH, INC.

By: /s/ WILLIAM CRUZ
    -----------------------
    
William Cruz, President