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                                                                     Exhibit 4.5

                                  CATUITY INC.

                             SUBSCRIPTION DOCUMENTS

CATUITY INC. IS OFFERING UP TO 270,000 SHARES OF ITS COMMON STOCK ("SHARES") AT
A PURCHASE PRICE OF US$7.50 PER SHARE.

THIS OFFERING IS MADE, AND SALES OF SHARES WILL BE MADE, ONLY TO PURCHASERS WHO
QUALIFY AS "ACCREDITED INVESTORS" UNDER REGULATION D PROMULGATED UNDER THE
SECURITIES ACT OF 1933. THE SECURITIES COVERED BY THIS SUBSCRIPTION AGREEMENT
HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR THE SECURITIES LAWS
OF ANY OTHER STATE.

EACH OFFEREE MAY, IF THE OFFEREE SO DESIRES, MAKE INQUIRIES OF CATUITY WITH
RESPECT TO CATUITY'S BUSINESS OR ANY OTHER MATTERS RELATING TO CATUITY AND ANY
INVESTMENT IN THE SECURITIES THEREOF, AND MAY OBTAIN ANY ADDITIONAL INFORMATION
THAT SUCH PERSON DEEMS TO BE NECESSARY IN CONNECTION WITH MAKING AN INVESTMENT
DECISION IN ORDER TO VERIFY THE ACCURACY OF THE INFORMATION CONTAINED IN THIS
SUBSCRIPTION AGREEMENT (TO THE EXTENT THAT CATUITY POSSESSES SUCH INFORMATION OR
CAN ACQUIRE IT WITHOUT UNREASONABLE EFFORT OR EXPENSE). IN CONNECTION WITH SUCH
INQUIRY, ANY DOCUMENTS WHICH ANY OFFEREE WISHES TO REVIEW WILL BE MADE AVAILABLE
FOR INSPECTION AND COPYING OR PROVIDED, UPON REQUEST, SUBJECT TO THE OFFEREE'S
AGREEMENT TO MAINTAIN SUCH INFORMATION IN CONFIDENCE AND TO RETURN THE SAME TO
CATUITY IF THE RECIPIENT DOES NOT PURCHASE THE SECURITIES OFFERED HEREUNDER. ANY
SUCH INQUIRIES OR REQUESTS FOR ADDITIONAL INFORMATION OR DOCUMENTS SHOULD BE
MADE IN WRITING TO CATUITY DIRECTED TO CATITY'S ADDRESS AS NOTED FURTHER DOWN IN
THIS DOCUMENT.

NO PERSON OTHER THAN AS PROVIDED FOR HEREIN HAS BEEN AUTHORIZED TO GIVE ANY
INFORMATION OR TO MAKE ANY REPRESENTATIONS OTHER THAN THOSE CONTAINED IN THIS
SUBSCRIPTION AGREEMENT IN CONNECTION WITH THE OFFER BEING MADE HEREBY, AND, IF
GIVEN OR MADE, SUCH INFORMATION OR REPRESENTATION MUST NOT BE RELIED ON AS
HAVING BEEN AUTHORIZED BY CATUITY.

THIS SUBSCRIPTION AGREEMENT DOES NOT CONSTITUTE AN OFFER TO SELL OR THE
SOLICITATION OF AN OFFER TO BUY ANY SECURITIES OTHER THAN THE SECURITIES OFFERED
HEREBY, NOR DOES IT CONSTITUTE AN OFFER TO SELL OR A SOLICITATION OF AN OFFER TO
BUY SUCH SECURITIES BY ANYONE IN ANY JURISDICTION IN WHICH SUCH OFFER OR
SOLICITATION IS NOT AUTHORIZED, OR IN WHICH THE PERSON MAKING SUCH OFFER OR
SOLICITATION IS NOT QUALIFIED TO DO SO.

PROSPECTIVE INVESTORS ARE NOT TO CONSTRUE THE CONTENTS OF THIS SUBSCRIPTION
AGREEMENT AS LEGAL, INVESTMENT OR TAX ADVICE. PROSPECTIVE INVESTORS SHOULD
CONSULT THEIR ADVISORS AS TO LEGAL,

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INVESTMENT, TAX AND RELATED MATTERS CONCERNING AN INVESTMENT BY SUCH PROSPECTIVE
INVESTORS IN CATUITY.

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                            SUBSCRIPTION INSTRUCTIONS

      In connection with a subscription for shares of common stock being offered
by Catuity, Inc., a Delaware corporation (the "Company"), the following
documents should be properly and fully completed and signed:

      1. SUBSCRIPTION AGREEMENT AND INVESTOR QUESTIONNAIRE. Please read this
document thoroughly. This must be completed and signed in accordance with the
instructions.

      2. SUBSCRIPTION PRICE. Subscription funds, in full, should be wired to the
following account:

                              [Account Information]

      3. DELIVERY INSTRUCTIONS AND QUESTIONS. Please return the completed and
signed subscription documents to:

                                  Catuity, Inc.
                            2711 E. Jefferson Avenue
                                Detroit, MI 48207
                      Attention: John Racine or Jack Lowry
                                Fax: 313-567-4734

      If you have any questions, please contact John Racine or Jack Lowry at
(313) 567-4348 or jackl@catuity.com.

      4. ANTICIPATED TIMING.

            Offering Commences:                September 8, 2005
            Subscription Agreements Due:       September 12, 2005
            Funds Due into Catuity Account:    September 12, 2005
            Final Allotments Made:             September 12, 2005
            Offering Closes:                   September 12, 2005
            Funds Released From Escrow:        Noon, September 16, 2005

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                SUBSCRIPTION AGREEMENT AND INVESTOR QUESTIONNAIRE

      1. SUBSCRIPTION. The undersigned (the "Subscriber") hereby irrevocably
subscribes for and agrees to purchase that number of Shares and to pay to
Catuity the purchase price set forth on the signature page hereof. The full
purchase price for the Shares is due on delivery of the Subscription Documents.
The date that Catuity accepts this Subscription Agreement and the Subscriber is
issued Shares shall be referred to herein as the "Closing Date."

      2. ACCEPTANCE OR REJECTION OF SUBSCRIPTION. Catuity reserves the right to
reject this subscription for Shares, in whole or in part, or to allot to
Subscriber fewer than the subscribed-for total amount, at any time prior to the
Closing Date for any reason whatsoever. Catuity shall promptly notify Subscriber
of the acceptance, rejection or allotment of Subscriber's subscription.

      3. ACCREDITED INVESTOR STATUS. Subscriber understands that, in order to
invest in Catuity, the Subscriber must be an "Accredited Investor" within the
meaning of Regulation D promulgated under the Securities Act of 1933, as amended
("Regulation D"). Subscriber hereby represents and warrants to Catuity that the
Subscriber is an Accredited Investor because he, she or it meets one or more of
the requirements set forth below. (Please mark all items which are applicable.)

      Entity Subscribers

      _____ The Subscriber is a trust whose sole trustee is a bank or savings
            and loan association as described in Regulation D.

      _____ The Subscriber is a corporation, a limited liability company, a
            partnership or other entity not formed for the specific purpose of
            acquiring the Shares in Catuity, with total assets in excess of
            $5,000,000.00.

      _____ The Subscriber is a trust not formed for the specific purpose of
            acquiring the Shares in Catuity, with total assets in excess of
            $5,000,000.00, and the person making the investment decision has
            such knowledge and experience in financial and business matters that
            he is capable of evaluating the merits and risks of an investment in
            Catuity.

      _____ The Subscriber is a bank as defined in Section 3(a)(2) of the
            Securities Act of 1933, as amended (the "Securities Act").

      _____ The Subscriber is a savings and loan association or other
            institution as defined in Section 3(a)(5)(A) of the Securities Act.

      _____ The Subscriber is a broker or dealer registered pursuant to Section
            15 of the Securities Exchange Act of 1934, as amended.

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      _____ The Subscriber is an insurance company as defined in Section 2(13)
            of the Securities Act.

      _____ The Subscriber is a revocable grantor trust, and the grantor is an
            Accredited Investor (i.e., meets one or more of the requirements set
            forth above--Indicate which requirements).

      _____ The Subscriber is an investment company registered under the
            Investment Fund Act of 1940, as amended, or a business development
            company as defined in Section 2(a)(48) of the Securities Act.

      _____ The Subscriber is an entity but does not meet either of the
            qualifications set forth above; however, each owner of equity
            interests in Subscriber qualifies as an Accredited Investor. Please
            attach a list of all owners and indicate how each equity owner
            qualifies as an Accredited Investor.

      Individual Subscribers

      _____ The Subscriber has an individual net worth, or joint net worth with
            his or her spouse, of more than $1,000,000.00.

      _____ The Subscriber had individual income (not including his or her
spouse's income) in excess of $200,000.00 in each of the two most recent years,
or joint income with his or her spouse in excess of $300,000.00 in each of those
years, and has a reasonable expectation of reaching the same income level in the
current year.

      4. REPRESENTATIONS, WARRANTIES AND AGREEMENTS. The Subscriber hereby
represents, warrants and agrees as follows, with the knowledge that Catuity will
rely upon the same in deciding whether to accept this subscription:

      (a) The Subscriber acknowledges that all documents, records and books
pertaining to this investment as requested by Subscriber have been made
available for inspection by it and its attorneys, accountants, investment
advisors and other representatives. The Subscriber and its advisors and
representatives have principally relied on information relating to Catuity
contained in its documents as publicly filed with the SEC, and also have had a
reasonable opportunity to ask questions of and receive answers from the officers
of Catuity concerning the business, affairs and prospects of Catuity, and all
such questions have been answered to the Subscriber's full satisfaction.

      (b) The Shares were not offered for sale to the Subscriber by means of:
(i) an advertisement, article, notice, letter, circular or other communication
published in any newspaper, magazine or similar medium or by other written
communication or broadcast over television or radio; or (ii) a seminar or
meeting held pursuant to public invitation or announcement; or (iii) any other
form of general solicitation or advertising.

      (c) All information contained in this Subscription Agreement and all other
information which the Subscriber has provided to Catuity is correct and complete
as of the date

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set forth on the signature page hereof, and, if there should be any material
change in such information before this subscription is accepted, the Subscriber
will immediately provide Catuity with such information.

      (d) If the Subscriber is an entity, (i) the Subscriber is duly organized,
validly existing and in good standing under all laws applicable to it and has
full power and authority to acquire the Shares in Catuity, and (ii) those
persons executing this Subscription Agreement on the Subscriber's behalf are
duly authorized to act for and bind the Subscriber.

      (e) The Subscriber and its stockholders, members, partners or
beneficiaries (if any) have adequate means of providing for their current needs
and possible personal contingencies, have no need for liquidity in this
investment, are able to bear the substantial economic risks of an investment in
Catuity for an indefinite period, and at the present time could afford a
complete loss of the investment. The Subscriber has such knowledge and
experience in financial and business matters that the Subscriber is capable of
evaluating the merits and risks of this investment. Upon acceptance of this
subscription, the Subscriber will have invested less than ten percent (10%) of
its total assets into Catuity.

      (f) The Subscriber recognizes that there is substantial economic risk
associated with an investment in Catuity, which could result in a complete loss
of investment. The Subscriber has carefully read and understands the Risk
Factors and other information disclosed in Catuity's public filings with the
U.S. Securities and Exchange Commission.

      (g) The Subscriber understands, or has consulted with its tax advisors
concerning, the tax consequences of an investment in Catuity. The Subscriber has
not received or relied upon any representations, warranties or assurances of
Catuity or any persons acting on its behalf concerning the tax aspects of an
investment in Catuity.

      (h) The Subscriber understands that the Shares have not been registered
under the Securities Act of 1933, as amended, or the securities laws of any
state. The Subscriber will not sell or otherwise transfer any Shares unless they
are registered under the Securities Act of 1933, as amended, and any applicable
state securities laws, or an exemption from such registration is available. The
Subscriber further agrees to enter into a Registration Rights Agreement with
Catuity and various other purchasers of Shares in this placement, and
understands that Catuity is under no other or further obligation to register the
Shares on its behalf or to assist it in complying with any exemption from
registration except as set forth in the Registration Rights Agreement. The
Subscriber is purchasing the Shares solely for its own account for investment
only and not for the account of any other person and not for distribution,
assignment or resale to others, and no other person has a direct or indirect
beneficial interest in the Shares.

      5. INDEMNIFICATION. The Subscriber hereby agrees to indemnify Catuity and
its directors, officers, employees, agents, their respective affiliates and
anyone acting on their behalf against all liability, damages, loss, costs and
expenses (including reasonable attorneys' fees and expenses) which any of them
may incur by reason of the Subscriber's failure to fulfill any of the
agreements, terms or conditions of this Subscription Agreement, or by reason of
the falsity of

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any representation or breach of any warranty made by the Subscriber herein or in
connection with the Operating Agreement, or in any document provided by the
Subscriber to Catuity.

      6. MISCELLANEOUS.

      (a) The Subscriber agrees that upon acceptance of this Subscription
Agreement by Catuity, the Subscriber's execution and delivery of this
Subscription Agreement is irrevocable and the Subscriber may not terminate or
revoke the same or any agreement made by the Subscriber hereunder, and that the
same shall survive the death or disability of the Subscriber and shall be
binding upon the Subscriber's heirs, executors, administrators, successors and
assigns; provided, however, that if the Subscriber is not satisfied with the
terms of the Operating Agreement or the offering memorandum describing the
investment in Catuity, when such documents are finalized, the Subscriber may
withdraw, and Catuity shall refund to the Subscriber, his, her or its
investment. The Subscriber agrees that, although after acceptance Catuity will
return to the Subscriber a copy of this Subscription Agreement, the acceptance
of this Subscription Agreement will be effective when an officer of Catuity
signs the appropriate form below without delivery or notice of such acceptance.

      (b) This Subscription Agreement constitutes the entire agreement among the
parties hereto with respect to the subject matter hereof and may be amended only
by a writing executed by all parties, except as otherwise provided herein.

      (c) This Subscription Agreement shall be construed and enforced in
accordance with, and governed by, the laws of the State of Delaware.

      7. SECURITIES LAWS PROVISION. The Subscriber has read, understands and
agrees to be bound by the following:

      THE SECURITIES SUBSCRIBED FOR HEREIN HAVE NOT BEEN APPROVED OR DISAPPROVED
BY THE SECURITIES AND EXCHANGE COMMISSION (THE "COMMISSION") OR ANY OTHER STATE
SECURITIES AGENCY, NOR HAS THE COMMISSION OR ANY OTHER STATE SECURITIES AGENCY
PASSED UPON THE ACCURACY OR ADEQUACY OF THE OFFERING DOCUMENTS. SUCH INTERESTS
HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR THE SECURITIES LAWS
OF ANY OTHER STATE AND ARE SUBJECT TO RESTRICTION ON TRANSFERABILITY AND SALE OF
SECURITIES AS SET FORTH IN THIS SUBSCRIPTION AGREEMENT. THE SUBSCRIBER AGREES
THAT SUCH INTERESTS WILL NOT BE SOLD WITHOUT REGISTRATION UNDER ALL APPLICABLE
SECURITIES LAWS OR EXEMPTION THEREFROM.

                       [Signatures to follow on next page]

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                              SUBSCRIBER SIGNATURE

      IN WITNESS WHEROF, the undersigned Subscriber hereby executes and delivers
this Subscription Agreement and Investor Questionnaire as of the date written
below.

Dated: September ___, 2005                         _____________________________
                                                   Print Name of Subscriber

                                                   By: _________________________
                                                              (Signature)

                                                   Title: ______________________
                                                             (if applicable)

Legal Residence of Subscriber:    ______________________________________________
                                  ______________________________________________

Mailing Address of Subscriber:    ______________________________________________
  (if different from above)       ______________________________________________

Telephone Number of Subscriber:   ______________________________________________

E-Mail Address of Subscriber:     ______________________________________________

Taxpayer Identification or Social
Security Number of Subscriber:    ______________________________________________

Total Capital Commitment:         $_______________(Minimum  is  $100,000
                                  subject to the discretion of Catuity to accept
                                  lesser amounts)

Share price:                      US$7.50 per share

SUBSCRIPTION ACCEPTED:

Dated: September ___, 2005                 Catuity Inc., a Delaware corporation

                                           By: ________________________________

                                           Its: ________________________________

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