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                                                                    EXHIBIT 10.3

                            INVESTOR RIGHTS AGREEMENT


                THIS INVESTOR RIGHTS AGREEMENT (the "Agreement") is entered into
this 28th day of December, 2001, by and between AspenBio, Inc., a Colorado
corporation (the "Company") and Cambridge Holdings, Ltd., a Colorado corporation
(the "Purchaser").

                                    RECITALS

        A.      On the date hereof, the Company and the Purchaser entered into a
Securities Purchase Agreement (the "Purchase Agreement"), pursuant to which
Purchaser acquired, and agreed to acquire, certain securities of the Company as
described in the Purchase Agreement. All capitalized terms used in this
Agreement shall have the same meanings as ascribed to such terms in the Purchase
Agreement.

        B.      Section 2.2 of the Purchase Agreement provides that the Parties
enter into this Agreement to provide rights for the Purchaser .

        C.      This Agreement is being executed and delivered at the Closing in
connection with provision for payment of the purchase price under the Purchase
Agreement.

                             STATEMENT OF AGREEMENT

        NOW THEREFORE, in consideration of the premises and of the respective
covenants and provisions herein contained, and intending to be legally bound
hereby, the Parties agree as follows:

1.      Certain Definitions.

        As used in this Agreement, the following terms shall have the meanings
ascribed to them below:

        "Affiliate" means (i) with respect to any Person, any other Person
directly or indirectly controlling or controlled by or under direct or indirect
common control with such specified Person or (ii) with respect to any
individual, the spouse, child, step-child, grandchild, niece, nephew or parent
of such Person, or the spouse thereof.

        "Common Stock" means the Common Stock of the Company and any equity
securities issued or issuable with respect to the Common Stock in connection
with a reclassification, recapitalization, merger, consolidation or other
reorganization.

        "Exchange Act" means the Securities Exchange Act of 1934, as amended.

        "Holder" means any Person owning of record Registrable Securities that
have not been sold to the public.

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        "Person" means any individual, corporation, limited liability company,
limited or general partnership, joint venture, association, joint-stock company,
trust, unincorporated organization or government or any agency or political
subdivisions thereof.

        "Registrable Securities" means any (i) of the Shares purchased pursuant
to the Purchase Agreement, (ii) shares of Common Stock issuable or issued upon
exercise of the Warrants and, (iii) any other shares of Common Stock issued or
issuable, directly or indirectly, with respect to the Common Stock referenced in
clauses (i) or (ii) or by way of stock dividend, stock split or combination of
shares. As to any particular Registrable Securities, such securities shall cease
to be Registrable Securities when (a) a registration statement filed pursuant to
a Demand Registration Request (as defined in Section 2.2 herein) or a Form S-3
Registration (as defined in Section 2.4 herein) with respect to such securities
shall have been declared effective under the Securities Act and the Company has
materially complied with Section 2.3(b) herein, or (b) such securities shall
have been disposed of in accordance with a registration described in Section 2.1
herein ("Piggyback Registration"), or (c) such securities shall have been sold
pursuant to Rule 144 (or any successor provision) under the Securities Act, or
(d) such securities are eligible for sale under Rule 144(k) (or any successor
provision) under the Securities Act. Provided, however, that Registrable
Securities which otherwise would cease to be considered Registrable Securities
as a result of item (a) above shall remain Registrable Securities solely for the
purposes of Section 2.1 herein.

        "SEC" means the United States Securities and Exchange Commission.

        "Securities Act" means the Securities Act of 1933, as amended.

2.      Registration Rights.

                2.1     Piggyback Registrations.

                        (a)     Piggyback Registrations. If, at any time prior
        to June 30, 2007 the Company proposes to register its Common Stock under
        the Securities Act in connection with the public offering of Common
        Stock (other than a registration relating solely to the sale of Common
        Stock to participants in an employee benefit plan or with respect to any
        corporate reorganization or other transaction under Rule 145 of the
        Securities Act) whether or not for its own account, the Company shall
        give prompt written notice of its intention to do so to the Holders.
        Upon the written request of any of the Holders made within 15 days
        following the receipt of any such written notice (which request shall
        specify the Registrable Securities intended to be disposed of by the
        Holders and the intended method of distribution thereof), the Company
        shall use commercially reasonable efforts to cause all such Registrable
        Securities to be registered under the Securities Act (with the
        securities which the Company at the time proposes to register) to permit
        the sale or other disposition by the Holders (in accordance with the
        intended method of distribution thereof) of the Registrable Securities
        to be so registered.

                        (b)     Abandonment or Delay. If, at any time after
        giving written notice of its intention to register its Common Stock and
        prior to the effective date of the



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        registration statement filed in connection with such registration, the
        Company shall determine for any reason not to register or to delay
        registration of its Common Stock, the Company may, at its election, give
        written notice of such determination to all Holders and (i) in the case
        of a determination not to register, shall be relieved of its obligation
        to register any Registrable Securities in connection with such abandoned
        registration, without prejudice, however, to the rights of Holders under
        Section 2.1(a), and (ii) in the case of a determination to delay such
        registration of its Common Stock shall be permitted to delay the
        registration of such Registrable Securities for the same period as the
        delay in registering its Common Stock.

                        (c)     Holder's Right to Withdraw. Any Holder shall
        have the right to withdraw its request for inclusion of its Registrable
        Securities in any registration statement pursuant to this Section 2.1 by
        giving written notice to the Company of its request to withdraw.

                        (d)     Underwriting Requirements. In connection with
        any offering involving an underwriting of the Common Stock, the Company
        shall not be required under Section 2.1 to include any of the
        Registrable Securities in such underwriting unless the Holders accept
        the terms of the underwriting as agreed upon between the Company and the
        underwriters selected by it (or by other persons entitled to select the
        underwriters), and then only in such quantity as the underwriters
        determine in their sole discretion will not jeopardize the success of
        the offering by the Company. If the total amount of securities,
        including Registrable Securities, requested by persons to be included in
        such offering exceeds the amount of securities that the underwriters
        determine in their sole discretion is compatible with the success of the
        offering, then the Company shall be required to include in the offering
        only that number of shares of Common Stock, including Registrable
        Securities, which the underwriters determine in their discretion will
        not jeopardize the success of the offering (the securities so included
        to be apportioned pro rata among the Persons according to the total
        amount of securities entitled to be included therein owned by each
        Person or in such proportions as shall mutually be agreed to by such
        Persons. In the event that the underwriters determine that the total
        amount of securities requested to be included in the offering exceeds
        the amount that the underwriters determine is compatible with the
        success of the offering, then the underwriters shall provide written
        notice of such determination to the Holders.

                2.2     Demand Registration.

                        (a)     Request for Registration. The Holders shall be
        entitled to one Demand Registration Request as defined herein. Subject
        to Section 2.2(c), at any time between September 30, 2002 and June 30,
        2006 one or more Holders holding at least a majority of the Registrable
        Securities then outstanding shall have the right to require the Company
        to file a registration statement under the Securities Act covering the
        Registrable



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        Securities, by delivering a written request therefor to the Company
        specifying the Registrable Securities to be included in such
        registration by such Holder(s) and the intended method of distribution
        thereof. Any such request pursuant to this Section 2.2(a) is referred to
        herein as the "Demand Registration Request" and the registration so
        requested is referred to herein as the "Demand Registration".

                        (b)     Registration. The Company shall, as
        expeditiously as possible following the Demand Registration Request, use
        commercially reasonable efforts to effect such registration under the
        Securities Act (including, without limitation, by means of a shelf
        registration pursuant to Rule 415 under the Securities Act if so
        requested and if the Company is then eligible to use such a
        registration) of the Registrable Securities which the Company has been
        so requested to register, for distribution in accordance with such
        intended method of distribution.

                        (c)     Limitations on Requested Registration. The
        rights of Holders to request the Demand Registration pursuant to Section
        2.2(a) are subject to the following limitations: (i) in no event shall
        the Holders be entitled to more than one Demand Registration Request,
        (ii) if the request is made prior to June 20, 2003 and the Board of
        Directors of the Company makes a reasonable good faith determination
        that the payment of the legal and accounting fees and other pertinent
        expenses incident to the filing and prosecution of the registration
        statement would have a material adverse effect on the financial
        condition of the Company, the Company shall not be required to comply
        with the Demand Registration Request, or (iii) if any of the Holders
        have participated in a Demand Registration or a Form S-3 Registration in
        the twelve-month period preceding the request. Provided, however, that
        the Company shall be required to comply with the Demand Registration
        Request if the Purchaser agrees to pay such expenses.

                        (d)     Company Registration. During the period starting
        with the date of filing of, and ending on a date 180 days after the
        effective date of, a registration subject to Section 2.1 hereof, the
        Company shall not be obligated to effect, or take any action to effect,
        any registration pursuant to this Section 2.2; provided that the Company
        is actively employing good faith and commercially reasonable efforts to
        cause such registration statement to become effective. In the event that
        the Company determines not to pursue a registration or to withdraw a
        registration that has been filed, notice of such action will be provided
        promptly by the Company to the Holders.

                        (e)     Underwriting Requirements. If the Holders intend
        to distribute the Registrable Securities by means of an underwriting,
        they shall so advise the Company as a part of their request made
        pursuant to Section 2.2(a). The underwriter will be selected by the
        Company and shall be reasonably acceptable to the Holders. In such
        event, the right of the Holder to include its Registrable Securities in
        such registration shall be conditioned upon the Holder's participation
        in such underwriting and the inclusion of such Holder's Registrable
        Securities in the underwriting to the extent provided herein. All
        Holders proposing to distribute their Common Stock through such
        underwriting shall (together with the Company as provided in Section 3)
        enter into an underwriting agreement in customary form with the
        underwriter or underwriters selected for such



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        underwriting. Notwithstanding any other provisions of this Section 2.2,
        if the underwriter advises the Holders in writing that marketing factors
        require a limitation of the number of shares to be underwritten, then
        the number of shares of Registrable Securities and other securities that
        may be included in the underwriting shall be allocated among all Holders
        and other Persons whose Common Stock of the Company the Company has
        agreed may be included in the offering (collectively, the "Selling
        Shareholders") in proportion (as nearly practicable) to the amount of
        Common Stock of the Company owned by the Holders and the other Selling
        Shareholders. In the event that notice is received from the underwriter
        that the number of shares to be underwritten should be limited, and the
        number of shares of Registrable Securities included in the offering is
        less than a majority of the Registrable Securities, then the offering
        shall not be deemed to be the Demand Registration Request.

                2.3     Registration Procedures. If and whenever the Company is
required by the provisions of this Agreement to use commercially reasonable
efforts to effect or cause the registration of any Registrable Securities under
the Securities Act as provided in this Agreement, the Company shall, as
expeditiously as possible:

                        (a)     prepare and file with the SEC a registration
        statement on an appropriate registration form of the SEC for the
        disposition of such Registrable Securities in accordance with the
        intended method of disposition thereof, which form (i) shall be selected
        by the Company and (ii) shall, in the case of a shelf registration, be
        available for the sale of the Registrable Securities by the Holders and
        such registration statement shall comply as to form in all material
        respects with the requirements of the applicable form and include all
        financial statements required by the SEC to be filed therewith, and the
        Company shall use its best efforts to cause such registration statement
        to become effective (provided, however, that before filing a
        registration statement or prospectus or any amendments or supplements
        thereto, or comparable statements under securities or blue sky laws of
        any jurisdiction, the Company will furnish to one counsel for the
        Holders participating in the planned offering and the underwriters, if
        any, copies of all such documents proposed to be filed (including all
        exhibits thereto), which documents will be subject to the reasonable
        review and reasonable comment of such counsel, and the Company shall not
        file any registration statement or amendment thereto or any prospectus
        or supplement thereto to which the underwriters, if any, shall
        reasonably object in writing);

                        (b)     prepare and file with the SEC such amendments
        and supplements to such registration statement and the prospectus used
        in connection therewith as may be necessary to keep such registration
        statement effective for such period (which shall not be required to
        exceed 180 days in the case of a Demand Registration and shall not
        exceed 90 days for all other registrations unless mutually agreed to in
        writing by the parties) as any seller of Registrable Securities pursuant
        to such registration statement shall request and to comply with the
        provisions of the Securities Act with respect to the sale or other
        disposition of all Registrable Securities covered by such registration
        statement in accordance with the intended methods of disposition by the
        seller or sellers thereof set forth in such registration statement;

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                        (c)     furnish, without charge, to each seller of such
        Registrable Securities and each underwriter, if any, of the securities
        covered by such registration statement such number of copies of such
        registration statement, each amendment and supplement thereto (in each
        case including all exhibits), and the prospectus included in such
        registration statement (including each preliminary prospectus) in
        conformity with the requirements of the Securities Act, and other
        documents, as such seller and underwriter may reasonably request in
        order to facilitate the public sale or other disposition of the
        Registrable Securities owned by such seller (the Company hereby
        consenting to the use in accordance with applicable law of each such
        registration statement (or amendment or post-effective amendment
        thereto) and each such prospectus (or preliminary prospectus or
        supplement thereto) by each such seller of Registrable Securities and
        the underwriters, if any, in connection with the offering and sale of
        the Registrable Securities covered by such registration statement or
        prospectus);

                        (d)     use its best efforts to register or qualify the
        Registrable Securities covered by such registration statement under such
        other securities or "blue sky" laws of such jurisdictions as any sellers
        of Registrable Securities or any managing underwriter, if any, shall
        reasonably request in writing, and do any and all other acts and things
        which may be reasonably necessary or advisable to enable such sellers or
        underwriter, if any, to consummate the disposition of the Registrable
        Securities in such jurisdictions, except that in no event shall the
        Company be required to qualify to do business as a foreign corporation
        in any jurisdiction where it would not, but for the requirements of this
        paragraph (d), be required to be so qualified, to subject itself to
        taxation in any such jurisdiction or to consent to general service of
        process in any such jurisdiction;

                        (e)     promptly notify each Holder selling Registrable
        Securities covered by such registration statement and each managing
        underwriter, if any: (i) when the registration statement, any
        pre-effective amendment, the prospectus or any prospectus supplement
        related thereto or post-effective amendment to the registration
        statement has been filed and, with respect to the registration statement
        or any post-effective amendment, when the same has become effective;
        (ii) of any request by the SEC or state securities authority for
        amendments or supplements to the registration statement or the
        prospectus related thereto or for additional information; (iii) of the
        issuance by the SEC of any stop order suspending the effectiveness of
        the registration statement or the initiation of any proceedings for that
        purpose; (iv) of the receipt by the Company of any notification with
        respect to the suspension of the qualification of any Registrable
        Securities for sale under the securities or blue sky laws of any
        jurisdiction or the initiation of any proceeding for such purpose; (v)
        of the existence of any fact of which the Company becomes aware which
        results in the registration statement, the prospectus related thereto or
        any document incorporated therein by reference containing an untrue
        statement of a material fact or omitting to state a material fact
        required to be stated therein or necessary to make any statement therein
        not misleading; and (vi) if at any time the representations and
        warranties contemplated by Section 3 below cease to be true and correct
        in all material respects, and, if the notification relates to an event
        described in clause (v), the Company shall promptly prepare and furnish
        to each such seller and each underwriter, if any, a reasonable number of
        copies of a prospectus supplemented or amended so that, as

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        thereafter delivered to the purchasers of such Registrable Securities,
        such prospectus shall not include an untrue statement of a material fact
        or omit to state a material fact required to be stated therein or
        necessary to make the statements therein in the light of the
        circumstances under which they were made not misleading;

                        (f)     enter into such customary agreements (including,
        if applicable, an underwriting agreement) and take such other actions as
        the Holders participating in such offering shall reasonably request in
        order to expedite or facilitate the disposition of such Registrable
        Securities. The Holders of the Registrable Securities which are to be
        distributed by such underwriters shall be parties to such underwriting
        agreement and may, at their option, require that the Company make to and
        for the benefit of such Holders the representations, warranties and
        covenants of the Company which are being made to and for the benefit of
        such underwriters and which are of the type customarily provided in
        secondary offerings;

                        (g)     if an opinion from the Company's counsel is
        delivered to any underwriters in the offering, the Company shall furnish
        to the Holders of Registrable Securities participating in the offering,
        a copy of such opinion and letter addressed to such Holders;

                        (h)     delivery promptly to the Holders of Registrable
        Securities participating in the offering and each underwriter, if any,
        copies of all correspondence between the Commission and the Company, its
        counsel or auditors and any memoranda relating to discussions with the
        Commission or its staff with respect to the registration statement,
        other than those portions of any such memoranda which contain
        information subject to attorney-client privilege with respect to the
        Company, and, upon receipt of such confidentiality agreements as the
        Company may reasonably request, make reasonably available for inspection
        by any seller of such Registrable Securities covered by such
        registration statement, by any underwriter, if any, participating in any
        disposition to be effected pursuant to such registration statement and
        by any attorney, accountant or other agent retained by any such seller
        or any such underwriter, all pertinent financial and other records,
        pertinent corporate documents and properties of the Company, and cause
        all of the Company's officers, directors and employees to supply all
        information reasonably requested by any such seller, underwriter,
        attorney, accountant or agent in connection with such registration
        statement provided the recipient of such information seeks such
        information in good faith and for a proper purpose;

                        (i)     make reasonably available its employees and
        personnel and otherwise provide reasonable assistance to the
        underwriters (taking into account the needs to the Company's businesses
        and the requirements of the marketing process) in the marketing of
        Registrable Securities in any underwritten offering;

                        (j)     cooperate with the Holders of Registrable
        Securities and the managing underwriters, if any, to facilitate the
        timely preparation and delivery of certificates not bearing any
        restrictive legends representing the Registrable Securities to be sold,
        and cause such Registrable Securities to be issued in such denominations
        and

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        registered in such names in accordance with the underwriting agreement
        prior to any sale of Registrable Securities to the underwriters or, if
        not an underwritten offering, in accordance with the instructions of the
        selling holders of the Registrable Securities at least three business
        days prior to any sale of Registrable Securities; and

                        (k)     take all such other commercially reasonable
        actions as are necessary or advisable in order to expedite or facilitate
        the disposition of such Registrable Securities.

                2.4     Form S-3 Registration. At any time between September 30,
2003 and June 30, 2006, in case the Company shall receive from one or more
Holders holding at least a majority of the Registrable Securities then
outstanding a written request that the Company effect a registration on Form S-3
and any related qualification or compliance with respect to all or part of the
Registrable Securities owned by such Holder or Holders, the Company will:

                        (a)     promptly give written notice of the proposed
        registration, and any related qualification or compliance, to all other
        Holders of Registrable Securities; and

                        (b)     as soon as practicable, effect such registration
        and all such qualifications and compliances made as to permit or
        facilitate the sale and distribution of all or such portion of such
        Holder's or Holders' Registrable Securities as are specified in such
        request, together will all such portion of the Registrable Securities of
        any other Holder or Holders joining in such request as are specified in
        a written request given within 15 days after receipt of such written
        notice from the Company; provided, however, that the Company shall not
        be obligated to effect any such registration, qualification or
        compliance pursuant to this Section 2.4:

                        (i)     if Form S-3 is not available for such offering
                by the Holders, or

                        (ii)    if the Holders together with the holders of any
                other securities of the Company entitled to inclusion in such
                registration, propose to sell Registrable Securities and such
                other securities (if any) at an aggregate price to the public of
                less than $500,000.

                        (iii)   if any of the Holders have participated in a
                Demand Registration, a Form S-3 Registration or a Piggyback
                Registration within the twelve-month period preceding the
                request.

                2.5     Registration Expenses.

                        (a)     "Expenses" shall mean any and all fees and
        expenses incident to the Company's performance of or compliance with
        this Article 2, including, without limitation: (i) SEC, stock exchange
        or NASD registration, listing and filing fees and all listing fees and
        fees with respect to the including of securities in NASDAQ, (ii) fees
        and expenses of compliance with state securities or "blue sky" laws and
        in connection with the preparation of a "blue sky" survey, including
        without limitation, reasonable fees and expenses of blue sky counsel,
        (iii) printing and copying expenses, (iv) messenger and

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        delivery expenses, (v) fees and disbursements of counsel for the
        Company, (vi) fees and disbursements of all independent public
        accountants (including the expenses of any audit and/or "cold comfort"
        letter) and fees and expenses of other persons, including special
        experts, retained by the Company, and (vii) any other fees and
        disbursements of underwriters, if any, customarily paid by issuers or
        sellers of securities (collectively, "Expenses").

                        (b)     The Company shall pay all Expenses with respect
        to any Demand Registration, whether or not it becomes effective or
        remains effective for the period contemplated by Section 2.3(b), and
        with respect to any registration effected under Section 2.1 or Section
        2.4.

                        (c)     Notwithstanding the foregoing, (x) the
        provisions of this Section 2.5 shall be deemed amended to the extent
        necessary to cause these expense provisions to comply with "blue sky"
        laws of each state in which the offering is made and (y) in connection
        with any registration hereunder, each Holder of Registrable Securities
        being registered shall pay all underwriting discounts and commissions
        and any transfer taxes, if any, attributable to the sale of such
        Registrable Securities, pro rata with respect to payments of discounts
        and commissions in accordance with the number of shares sold in the
        offering by such Holder, and (z) the Company shall, in the case of all
        registrations under this Article 2, be responsible for all its internal
        expenses (including, without limitation, all salaries and expenses of
        its officers and employees performing legal or accounting duties).

                2.6     Furnish Information. It shall be a condition precedent
to the obligations of the Company to take any action pursuant to this Section 2
with respect to the Registrable Securities of any Holder that such Holder shall
furnish to the Company such information regarding itself, the Registrable
Securities held by it, and the intended method of disposition of such securities
as shall be required to effect the registration of such Holder's Registrable
Securities.

                2.7     Indemnification.

                        (a)     In the event of any registration of any
        securities of the Company under the Securities Act pursuant to this
        Article 2, the Company will, and hereby does, indemnify and hold
        harmless, to the fullest extent permitted by law, each Holder of
        Registrable Securities, its directors, officers and representatives, and
        each other person, if any, who controls such Holder within the meaning
        of the Securities Act, against any and all losses, claims, damages or
        liabilities, joint or several, actions or proceedings (whether commenced
        or threatened) in respect thereof ("Claims") and expenses (including
        reasonable fees of counsel and any amounts paid in any settlement
        effected with the Company's consent, which consent shall not be
        unreasonably withheld or delayed) to which each such indemnified party
        may become subject under the Securities Act or otherwise, insofar as
        such Claims or expenses arise out of or are based upon (i) any untrue
        statement or alleged untrue statement of a material fact contained in
        any registration statement under which such securities were registered
        under the Securities



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        Act, together with the documents incorporated by reference therein, or
        the omission or alleged omission to state therein a material fact
        required to be stated therein or necessary to make the statements
        therein not misleading, or (ii) any untrue statement or alleged untrue
        statement of a material fact contained in any preliminary, final or
        summary prospectus or any amendment or supplement thereto, together with
        the documents incorporated by reference therein, or the omission or
        alleged omission to state therein a material fact required to be stated
        therein or necessary in order to make the statements therein, in the
        light of the circumstances under which they were made, not misleading;
        provided, however, that the Company shall not be liable to any such
        indemnified party in any such case to the extent such Claim or expense
        arises out of or is based upon any untrue statement or alleged untrue
        statement of a material fact or omission or alleged omission of a
        material fact in such registration statement or amendment thereof or
        supplement thereto or in any such prospectus or any preliminary, final
        or summary prospectus in reliance upon and in conformity with written
        information furnished to the Company by or on behalf of such indemnified
        party specifically for use therein. Such indemnity and reimbursement of
        expenses shall remain in full force and effect regardless of any
        investigation made by or on behalf of such indemnified party and shall
        survive the transfer of such securities by such seller.

                        (b)     In the event of any registration of any
        securities of the Company under the Securities Act pursuant to this
        Article 2, the Holders of Registrable Securities will, and hereby
        indemnify and hold harmless, to the fullest extent permitted by law, the
        Company, its shareholders, directors, officers, agents and
        representatives, and each other person, if any, who controls the Company
        within the meaning of the Securities Act, against any and all losses,
        claims, damages or liabilities, joint or several, actions or proceedings
        (whether commenced or threatened) in respect thereof ("Claims") and
        expenses (including reasonable fees of counsel and any amounts paid in
        any settlement effected with the Holders' consent, which consent shall
        not be unreasonably withheld or delayed) to which each such indemnified
        party may become subject under the Securities Act or otherwise, insofar
        as such Claims or expenses arise out of or are based upon (i) any untrue
        statement or alleged untrue statement of a material fact contained in
        any registration statement under which such securities were registered
        under the Securities Act, together with the documents incorporated by
        reference therein, or the omission or alleged omission to state therein
        a material fact required to be stated therein or necessary to make the
        statements therein not misleading, or (ii) any untrue statement or
        alleged untrue statement of a material fact contained in any
        preliminary, final or summary prospectus or any amendment or supplement
        thereto, together with the documents incorporated by reference therein,
        or the omission or alleged omission to state therein a material fact
        required to be stated therein or necessary in order to make the
        statements therein, in the light of the circumstances under which they
        were made, not misleading; provided, however, that the Holders shall not
        be liable to any such indemnified party in any such case to the extent
        such Claim or expense arises out of or is based upon any untrue
        statement or alleged untrue statement of a material fact or omission or
        alleged omission of a material fact in such registration statement or
        amendment thereof or supplement thereto or in any such prospectus or any
        preliminary, final or summary



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        prospectus unless it is contained in the written information furnished
        to the Company by or on behalf of such Holder specifically for use
        therein; provided, further, that the obligation to indemnify will be
        individual to each Holder and will be limited to the amount of proceeds
        received by such Holder from the sale of Registrable Securities pursuant
        to such registration statement.. Such indemnity and reimbursement of
        expenses shall remain in full force and effect regardless of any
        investigation made by or on behalf of such indemnified party and shall
        survive the transfer of such securities by such seller.

                        (c)     Any person entitled to indemnification under
        this Agreement shall notify promptly the indemnifying party in writing
        of the commencement of any action or proceeding with respect to which a
        claim for indemnification may be made pursuant to this Section 2.7, but
        the failure of any indemnified party to provide such notice shall not
        relieve the indemnifying party of its obligations under the preceding
        paragraphs of this Section 2.7, except to the extent the indemnifying
        party is materially prejudiced thereby and shall not relieve the
        indemnifying party from any liability which it may have to any
        indemnified party otherwise than under this Section 2. In case any
        action or proceeding is brought against an indemnified party and it
        shall notify the indemnifying party of the commencement thereof, the
        indemnifying party shall be entitled to participate therein and, unless
        in the reasonable opinion of outside counsel to the indemnified party a
        conflict of interest between such indemnified and indemnifying parties
        may exist in respect of such claim, to assume the defense thereof
        jointly with any other indemnifying party similarly noticed, to the
        extent that it chooses, with counsel reasonably satisfactory to such
        indemnified party, and after notice from the indemnifying party to such
        indemnified party that it so chooses, the indemnifying party shall not
        be liable to such indemnified party for any legal or other expenses
        subsequently incurred by such indemnified party in connection with the
        defense thereof other than reasonable costs of investigation; provided,
        however, that (i) if the indemnifying party fails to take reasonable
        steps necessary to defend diligently the action or proceeding within 20
        days after receiving notice from such indemnified party that the
        indemnified party believes it has failed to do so; or (ii) if such
        indemnified party who is a defendant in any action or proceeding which
        is also brought against the indemnifying party reasonably shall have
        concluded that there may be one or more legal defenses available to such
        indemnified party which are not available to the indemnifying party; or
        (iii) if representation of both parties by the same counsel is otherwise
        inappropriate under applicable standards of professional conduct, then,
        in any such case, the indemnified party shall have the right to assume
        or continue its own defense as set forth above, and the indemnifying
        party shall be liable for any expenses therefor. No indemnifying party
        shall, without the written consent of the indemnified party, effect the
        settlement or compromise of, or consent to the entry of any judgment
        with respect to, any pending or threatened action or claim in respect of
        which indemnification or contribution may be sought hereunder (whether
        or not the indemnified party is an actual or potential party to such
        action or claim) unless such settlement, compromise or judgment (A)
        includes an unconditional release of the indemnified party from all
        liability arising out of such action or claim and (B) does not include a
        statement as to or an admission of fault, culpability or a failure to
        act, by or on behalf of any indemnified party.


                                     - 11 -
<PAGE>

                        (d)     If for any reason the foregoing indemnity is
        unavailable or is insufficient to hold harmless an indemnified party
        under Section 2.7 or each indemnifying party shall contribute to the
        amount paid or payable by such indemnified party as a result of any
        Claim in such proportion as is appropriate to reflect the relative fault
        of the indemnifying party, on the one hand, and the indemnified party,
        on the other hand, with respect to such offering of securities. The
        relative fault shall be determined by reference to, among other things,
        whether the untrue or alleged untrue statement of a material fact or the
        omission or alleged omission to state a material fact relates to
        information supplied by the indemnifying party or the indemnified party
        and the parties' relative intent, knowledge, access to information and
        opportunity to correct or prevent such untrue statement or omission. If,
        however, the allocation provided in the second preceding sentence is not
        permitted by applicable law, then each indemnifying party shall
        contribute to the amount paid or payable by such indemnified party in
        such proportion as is appropriate to reflect not only such relative
        faults but also the relative benefits of the indemnifying party and the
        indemnified party as well as any other relevant equitable
        considerations. The parties hereto agree that it would not be just and
        equitable if contributions pursuant to this Section 2.7(d) were to be
        determined by pro rata allocation or by any other method of allocation
        which does not take into account the equitable considerations referred
        to in the preceding sentences of this Section 2.7(d). The amount paid or
        payable in respect of any Claim shall be deemed to include any legal or
        other expenses reasonably incurred by such indemnified party in
        connection with investigating or defending any such Claim. No person
        guilty of fraudulent misrepresentation (within the meaning of Section
        11(t) of the Securities Act) shall be entitled to contribution from any
        person who was not guilty of such fraudulent misrepresentation.



                                     - 12 -
<PAGE>


        2.8     Underwritten Offerings. If requested by the underwriters for any
underwritten offering by the Holders of Registrable Securities pursuant to a
registration requested under Section 2, the Company shall enter into a customary
underwriting agreement with the underwriters. Such underwriting agreement shall
be reasonably satisfactory in form and substance to the Holders and shall
contain such representations and warranties by, and such other agreements on the
part of, the Company and such other terms as are generally included in the
underwriting agreement of such underwriters, including, without limitations,
indemnities and contribution agreements.

3.      Rule 144 Reporting. With a view of making available to the Holders the
benefits of certain rules and regulations of the SEC which may permit the sale
of the Registrable Securities to the public without registration, the Company
agrees to use its best efforts to:

                        (a)     Make a keep public information available, as
        those terms are understood and defined in SEC Rule 144 or any successor
        rule promulgated under the Securities Act, at all times after the
        effective date of the first registration filed by the Company for an
        offering of its securities to the general public;

                        (b)     File with the SEC, in a timely manner, all
        reports and other documents required of the Company under the Exchange
        Act; and

                        (c)     So long as Holder owns any Registrable
        Securities, furnish to such Holder forthwith upon request a written
        statement by the Company as to its compliance with the reporting
        requirements of Rule 144 and of the Exchange Act at any time after it
        has become subject to such reporting requirements.

4.      Covenants of the Company. The Company covenants as follows:

        4.1     Board of Directors. The Company shall use its best efforts to
have the Board hold a minimum of three meetings per year. During the period from
the date thereof through June 30, 2003, so long as Purchaser owns a minimum of
250,000 Shares, the Company shall use its best efforts to insure that the
Purchaser shall be entitled to appoint one director to the Board. Unless
instructed otherwise by the Purchaser, the person so entitled to be appointed to
the Board shall be Gregory Pusey.

        4.2     Committees. The Company shall establish and maintain a
Compensation and Audit Committee, each of which shall have no more than three
members. Until at least June 20, 2003, Greg Pusey shall serve as a member of the
Compensation Committee.

        4.3     Expenses of Directors. The Company shall promptly reimburse, in
full, the director of the Company who has been designated by the Purchaser for
all of such director's reasonable out-of-pocket expenses incurred in attending
each meeting of the Board or any Committee thereof and any other reasonable
expenses incurred by such director while acting on the Company's behalf at the
request of the Company.

        4.4     Non-Disclosure and Invention Agreements. The Company shall
require all officers, employees, consultants and advisors now or hereafter
employed or engaged by the



                                     - 13 -
<PAGE>

Company who have or shall have access to proprietary information relating to the
Company to enter into nondisclosure and development agreements in form and
substance satisfactory to the Company's Board.

        4.5     Insurance. The Company shall at all times maintain in full force
and effect from a financially sound and reputable insurer a director's and
officer's liability insurance policy in the amount of not less $1 million
covering any representative of the Purchaser who is a director of the Company.

        4.6     Size of the Board of Directors. From the date hereof to December
20, 2002, the size of the Company's Board shall not be increased to more than
five members without the Purchaser's approval.

        4.7     Stock Options. From the date hereof until December 20, 2002, the
Company shall restrict stock option or stock award grants to its employees and
consultants to a limit of 900,000 shares at an exercise price of $1.00 or
greater (exclusive of directors) and will not increase the limit without the
Purchaser's approval. It is understood that the Company has recently granted
options purchase up to 200,000 shares of Common Stock at $1.00 per share to its
directors and prior to December 20, 2002, which shall not reduce the 900,000
available options or awards.

5.      General.


        5.1     Amendments and Waivers. This Agreement may be amended, modified,
supplemented or waived only upon the written agreement of the party against whom
enforcement of such amendment, modification, supplement or waiver is sought.

        5.2     Notices. All notices, elections, request, demands or other
communications hereunder shall be in writing and shall be deemed given at the
time delivered personally or by fax or upon receipt if deposited in the United
States mail, certified or registered, return receipt requested, postage prepaid
addressed to the parties as follows (or to such other person or place, written
notice of which any party hereto shall have given to the other):

               (a)  If to the Purchaser:   Cambridge Holdings, Ltd.
                                           106 S. University Boulevard #14
                                           Denver, Colorado  80209
                                           Attention:  Gregory Pusey, President
                                           Telephone:  (303) 722-4008
                                           Facsimile:  (303) 722-4011

                    With a Copy to:        Patton Boggs LLP
                                           1660 Lincoln Street, Suite 1900
                                           Denver, Colorado  80264
                                           Attention:  Robert M. Bearman, Esq.
                                           Telephone:  (303) 894-6169
                                           Facsimile:  (303) 894-9239

                                     - 14 -
<PAGE>

               (b)  If to Company:         AspenBio, Inc.
                                           8100 Southpark Way, Building B-1
                                           Littleton, Colorado  80120
                                           Attention:  Roger Hurst, President
                                           Telephone:  (303) 794-2000
                                           Facsimile:  (303) 798-8332

                    With a Copy to:        Krendl Krendl Sachnoff & Way PC
                                           370 17th Street, Suite 5350
                                           Denver, Colorado  80202
                                           Telephone:  (303) 629-2600
                                           Facsimile :  (303) 629-2606
                                           Attention:  Cathy S. Krendl, Esq.

5.3     Miscellaneous.

                (a)     This Agreement shall be binding upon and inure to the
benefit of and be enforceable by the parties hereto and the respective
successors, personal representatives and assigns. No Person other than a Holder
shall be entitled to any benefits under this Agreement, except as otherwise
expressly provided herein.

                (b)     This Agreement as well as the Securities Purchase
Agreement (and the Related Agreements referred to therein) between the parties
of even date (with the documents referred to herein or delivered pursuant
hereto) embodies the entire agreement and understanding between the parties
hereto and supersedes all prior agreements and understanding relating to the
subject matter hereof.

                (c)     This Agreement shall be construed and enforced in
accordance with and governed by the laws of the State of Colorado without giving
effect to the conflicts of law principles thereof.

                (d)     The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof. All
section references are to this Agreement unless otherwise expressly provided.

                (e)     This Agreement may be executed in any number of
counterparts, each of which shall be an original, but all of which together
shall constitute one instrument.

                (f)     Any term or provision of this Agreement which is invalid
or unenforceable in any jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such invalidity or unenforceability without
rendering invalid or unenforceable the remaining terms and provisions of this
Agreement or affecting the validity or enforceability of any of the terms or
provisions of this Agreement in any other jurisdiction.


                                     - 15 -
<PAGE>

                (g)     The parties hereto acknowledge that there would be no
adequate remedy at law if any party fails to perform any of its obligations
hereunder, and accordingly agree that each party, in addition to any other
remedy to which it may be entitled at law or in equity, shall be entitled to
injunctive relief, including specific performance, to enforce such obligations
without the posting of any bond, and, if any action should be brought in equity
to enforce any of the provisions of this Agreement, none of the parties hereto
shall raise the defense that there is an adequate remedy at law.

                (h)     Each party hereto shall do and perform or cause to be
done and performed all such further acts and things and shall execute and
deliver all such other agreements, certificates, instruments, and documents as
any other party hereto reasonably may request in order to carry out the intent
and accomplish the purposes of this Agreement and the consummation of the
transactions contemplated hereby.

                            [SIGNATURE PAGE FOLLOWS]



                                     - 16 -
<PAGE>


               IN WITNESS WHEREOF, the undersigned have executed this Inventory
Rights Agreement as of the date set forth above.


                             ASPENBIO, INC.

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


                             CAMBRIDGE HOLDINGS, LTD.

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



                                     - 17 -