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                                                                     EXHIBIT 4.1



                                  QUOVADX, INC.

                          REGISTRATION RIGHTS AGREEMENT


         This Registration Rights Agreement (this "Agreement") is made as of
December 14, 2001, between Quovadx, Inc., a Delaware corporation having its
principal place of business at 6400 S. Fiddler's Green Circle, Suite 1400,
Englewood, Colorado (the "Acquiror") and Francis Carden, an individual currently
residing at 6271 Indian River Drive, Norcross, Georgia 30092 (the
"Shareholder").

                                    RECITALS

         A. The Acquiror and the Shareholder are parties to a Share Acquisition
Agreement dated as of December 13, 2001 (the "Acquisition Agreement"), pursuant
to which the Acquiror is purchasing from the Shareholder, and the Shareholder is
selling to the Acquiror, all of the issued and outstanding share capital of
Pixel Innovations Ltd., a company incorporated under the laws of England and
Wales (the "Acquisition");

         B. In connection with the Acquisition, the Acquiror is issuing to the
Shareholder 201,794 shares of its common stock, par value $0.01 per share (the
"Shares"); and

         C. The Acquisition Agreement provides for the execution and delivery of
this Agreement at the closing of the transactions contemplated thereby which
grants the Shareholder certain rights to have the Shares registered under the
Securities Act of 1933, as amended;

         NOW, THEREFORE, in consideration of the premises and the mutual
covenants contained herein and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereby
agree as follows:


                                    SECTION 1

                 RESTRICTIONS ON TRANSFERABILITY OF SECURITIES;
               COMPLIANCE WITH SECURITIES ACT; REGISTRATION RIGHTS

         1.1 CERTAIN DEFINITIONS. Unless otherwise indicated, the terms in this
Agreement shall have the same meanings as those terms in the Purchase Agreement.
As used in this Agreement, the following terms shall have the following
respective meanings:

         "Commission" shall mean the Securities and Exchange Commission or any
other federal agency at the time administering the Securities Act.

         "Common Stock" shall mean the common stock, par value $0.01 per share,
of the Acquiror.

         The terms "register," "registered" and "registration" refer to a
registration effected by preparing and filing a registration statement in
compliance with the Securities Act, and the declaration or ordering of the
effectiveness of such registration statement.


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         "Registration Expenses" shall mean all expenses, except as otherwise
stated in the definition of the term "Selling Expenses" as set forth below,
incurred by the Acquiror in complying with Section 1.2 hereof, including,
without limitation, all registration, qualification and filing fees, printing
expenses, escrow fees, fees and disbursements of counsel for the Acquiror, blue
sky fees and expenses, the expense of any special audits incident to or required
by any such registration.

         "Securities Act" shall mean the Securities Act of 1933, as amended, or
any similar federal statute and the rules and regulations of the Commission
thereunder, all as the same shall be in effect at the time.

         "Selling Expenses" shall mean all selling commissions and stock
transfer taxes applicable to the Shares being sold by the Shareholder.

         1.2 MANDATORY REGISTRATION. The Acquiror shall use its reasonable best
efforts to prepare and file with the Commission, within thirty (30) days after
the closing of the Acquisition, a registration statement under the Securities
Act registering the resale of the Shares by the Shareholder (the "Registration
Statement"). The Acquiror shall use its reasonable best efforts to cause the
Registration Statement to be declared effective by the Commission as soon as
possible after such filing (the "Effective Date").

         1.3 EXPENSES OF REGISTRATION. All Registration Expenses incurred in
connection with all registrations pursuant to Section 1.2 shall be borne by the
Acquiror. Unless otherwise stated, all Selling Expenses shall be borne by the
Shareholder.

         1.4 REGISTRATION PROCEDURES. At its expense the Acquiror will:

             (a) Prepare and file with the Commission the Registration Statement
with respect to the Shares and use its best efforts to cause such Registration
Statement to become effective as soon as possible after the filing thereof, and
keep the Registration Statement effective until one year after its date of
effectiveness.

             (b) Furnish to the Shareholder, and to the Shareholder's brokers,
such reasonable number of copies of the registration statement, preliminary
prospectus, final prospectus and such other documents as the Shareholder or his
brokers may reasonably request in order to facilitate the resale of the Shares.

         1.5 SUSPENSION OF REGISTRATION. The Acquiror shall promptly notify the
Shareholder of (i) the issuance by the Commission of a stop order suspending the
effectiveness of the Registration Statement, (ii) the happening of any event, of
which the Acquiror has knowledge, as a result of which the prospectus included
in the Registration Statement, as then in effect, includes an untrue statement
of a material fact or omission to state a material fact required to be stated
therein or necessary to make the statements therein not misleading, and (iii)
the occurrence or existence of any pending corporate development that, in the
reasonable discretion of the Acquiror, makes it appropriate to suspend the
availability of the Registration Statement to comply with Commission rules. In
each case the Acquiror shall use commercially reasonable efforts to promptly
prepare a supplement or amendment to the Registration Statement to correct such
untrue statement or omission, and deliver such number of copies of such
supplement or amendment to the Shareholder as the Shareholder may reasonably
request; provided; however, that the Acquiror may delay to the extent permitted
by law the disclosure of material non-public information concerning the Acquiror
the disclosure of which at the time is not, in the good faith opinion of the
Acquiror, in the best interests of the Acquiror (an "Allowed Delay"). There
shall be no more than two Allowed Delays in any 365-day period, and no single
Allowed Delay shall exceed 60 consecutive days. The Acquiror shall promptly
notify the Shareholder in writing of the existence of an Allowed Delay and shall
advise the Shareholder in writing to cease all sales under the Registration
Statement until the end of the Allowed Delay.


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         1.6 INDEMNIFICATION.

             (a) The Acquiror will indemnify the Shareholder against all
expenses, claims, losses, damages or liabilities (or actions in respect
thereof), including any of the foregoing incurred in settlement of any
litigation, commenced or threatened, arising out of or based on any untrue
statement (or alleged untrue statement) of a material fact contained in any
registration statement, prospectus, offering circular or other document, or any
amendment or supplement thereto, incident to any such registration,
qualification or compliance, or based on any omission (or alleged omission) to
state therein a material fact required to be stated therein or necessary to make
the statements therein, in light of the circumstances in which they were made,
not misleading, or any violation by the Acquiror of the Securities Act, the
Exchange Act, state securities law or any rule or regulation promulgated under
such laws applicable to the Acquiror in connection with any such registration,
qualification or compliance, and within a reasonable period the Acquiror will
reimburse each the Shareholder for any legal and any other expenses reasonably
incurred in connection with investigating, preparing or defending any such
claim, loss, damage, liability or action; provided, however, that the Acquiror
will not be liable in any such case to the extent that any such claim, loss,
damage, liability or expense arises out of or is based on any untrue statement
or omission or alleged untrue statement or omission, made in reliance upon and
in conformity with information furnished to the Acquiror by the Shareholder for
use in such registration statement, prospectus, offering circular or other
document.

             (c) The Shareholder will indemnify the Acquiror, each of its
directors and officers, each underwriter, if any, of the Acquiror's securities
covered by such a registration statement, each person who controls the Acquiror
or such underwriter within the meaning of Section 15 of the Securities Act,
against all claims, losses, damages and liabilities (or actions in respect
thereof) arising out of or based on any untrue statement (or alleged untrue
statement) of a material fact contained in any such registration statement,
prospectus, offering circular or other document, or any omission (or alleged
omission) to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading, and within a reasonable
period will reimburse the Acquiror, its directors, officers, persons,
underwriters or control persons for any legal or any other expenses reasonably
incurred in connection with investigating or defending any such claim, loss,
damage, liability or action, in each case to the extent, but only to the extent,
that such untrue statement (or alleged untrue statement) or omission (or alleged
omission) is made in such registration statement, prospectus, offering circular
or other document in reliance upon and in conformity with information furnished
to the Acquiror by the Shareholder for use in such registration statement,
prospectus, offering circular or other document.

             (d) Each party entitled to indemnification under this Section 1.6
(the "Indemnified Party") shall give notice to the party required to provide
indemnification (the "Indemnifying Party") promptly after such Indemnified Party
has actual knowledge of any claim as to which indemnity may be sought, and shall
permit the Indemnifying Party to assume the defense of any such claim or any
litigation resulting therefrom, provided that counsel for the Indemnifying
Party, who shall conduct the defense of such claim or litigation, shall be
approved by the Indemnified Party (whose approval shall not unreasonably be
withheld), and the Indemnified Party may participate in such defense at such
party's expense, and provided further that the failure of any Indemnified Party
to give notice as provided herein shall not relieve the Indemnifying Party of
its obligations under this Section 1 unless the failure to give such notice is
materially prejudicial to an Indemnifying Party's ability to defend such action
and provided further, that the Indemnifying Party shall not assume the defense
for matters as to which there is a conflict of interest or separate and
different defenses. No Indemnifying Party, in the defense of any such claim or
litigation, shall, except with the consent of each Indemnified Party, consent to
entry of any judgment or enter into any settlement which does not include as an
unconditional term thereof the giving by the claimant or plaintiff to such
Indemnified Party of a release from all liability in respect to such claim or
litigation.


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         1.7 INFORMATION BY SHAREHOLDER. The Shareholder shall furnish to the
Acquiror such information regarding the Shareholder, the Shares and the
distribution proposed by the Shareholder or as the Acquiror may reasonably
request and as shall be required in connection with any registration,
qualification or compliance referred to in this Section 1.

                                    SECTION 2

                                  MISCELLANEOUS

         2.1 GOVERNING LAW. This Agreement shall be governed in all respects by
the internal laws of the State of Colorado.

         2.2 SURVIVAL. The covenants and agreements made herein shall survive
the closing of the transactions contemplated hereby.

         2.3 SUCCESSORS AND ASSIGNS. Except as otherwise provided herein, the
provisions hereof shall inure to the benefit of, and be binding upon, the
successors, assigns, heirs, executors and administrators of the parties hereto.

         2.4 ENTIRE AGREEMENT; AMENDMENT. This Agreement and the Acquisition
Agreement constitute the full and entire understanding and agreement between the
parties with regard to the subjects hereof and thereof, and no party shall be
liable or bound to any other party in any manner by any warranties,
representations or covenants except as specifically set forth herein or therein.
Except as expressly provided herein, neither this Agreement nor any term hereof
may be amended, waived, discharged or terminated other than by a written
instrument signed by the party against whom enforcement of any such amendment,
waiver, discharge or termination is sought.

         2.5 NOTICES, ETC. All notices and other communications required or
permitted hereunder shall be in writing and shall be mailed by registered or
certified mail, postage prepaid, telecopied or otherwise delivered by hand or by
messenger. Each such notice or other communication shall for all purposes of
this Agreement be treated as effective or having been given when delivered if
delivered personally or telecopied, or, if sent by mail, at the earlier of its
receipt or 72 hours after the same has been deposited in a regularly maintained
receptacle for the deposit of the United States mail, addressed and mailed as
aforesaid.

         2.6 DELAYS OR OMISSIONS. Except as expressly provided herein, no delay
or omission to exercise any right, power or remedy accruing to any party to this
Agreement upon any breach or default of any other party under this Agreement,
shall impair any such right, power or remedy of such nondefaulting party nor
shall it be construed to be a waiver of any such breach or default, or an
acquiescence therein, or of or in any similar breach or default thereafter
occurring; nor shall any waiver of any single breach or default be deemed a
waiver of any other breach or default theretofore or thereafter occurring. Any
waiver, permit, consent or approval of any kind or character on the part of any
party of any breach or default under this Agreement, or any waiver on the part
of any holder of any provisions or conditions of this Agreement, must be in
writing and shall be effective only to the extent specifically set forth in such
writing. All remedies, either under this Agreement or by law or otherwise
afforded to any party to this Agreement, shall be cumulative and not
alternative.

         2.7 COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which shall be enforceable against the parties actually
executing such counterparts, and all of which together shall constitute one
instrument.


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         2.8 SEVERABILITY. In the event that any provision of this Agreement
becomes or is declared by a court of competent jurisdiction to be illegal,
unenforceable or void, this Agreement shall continue in full force and effect
without said provision.

         2.9 TITLES AND SUBTITLES. The titles and subtitles used in this
Agreement are used for convenience only and are not considered in construing or
interpreting this Agreement.

The foregoing Agreement is hereby executed as of the date first above written.


"ACQUIROR"                 QUOVADX, INC.

                           By:    /s/ Linda K. Wackwitz
                              -------------------------------------------------

                           Name:    Linda K. Wackwitz
                                -----------------------------------------------

                           Title:  Executive Vice President and General Counsel
                                 ----------------------------------------------



"SHAREHOLDER"              FRANCIS CARDEN

                              /s/ Francis Carden
                           ----------------------------------------------------