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                                                                EXHIBIT 10.18(d)

                            INVESTOR RIGHTS AGREEMENT


                  THIS INVESTOR RIGHTS AGREEMENT (the "Agreement") is entered
into this 5th day of July, 2002, by and between AspenBio, Inc., a Colorado
corporation (the "Company") and Michael S. Smith, a resident of Englewood,
Colorado (the "Purchaser").

                                    RECITALS

         A. On the date hereof, the Purchaser acquired from the Company a
convertible note in the principal amount of $500,000 (the "Note") and a warrant
to purchase up to 275,000 shares of Common Stock (the "Warrant") in
consideration of the Purchaser's agreement to advance funds to the Company.

         B. The Purchaser required that the Company enter into this Agreement to
provide rights for the Purchaser as a condition to the Purchaser's agreement to
advance funds to the Company.

                             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.

         "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.



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         "Registrable Securities" means any (i) of the shares of Common Stock
issuable or issued upon conversion of the Note, (ii) shares of Common Stock
issuable or issued upon exercise of the Warrant, (iii) any shares of Common
Stock Purchaser now owns or hereinafter acquires, and (iv) any other shares of
Common Stock issued or issuable, directly or indirectly, with respect to the
Common Stock referenced in clauses (i), (ii) or (iii) 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) 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 between
         September 30, 2002 and June 30, 2005 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 Purchaser. Upon the written request of the Purchaser 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 Purchaser and the intended method of distribution thereof), the
         Company shall 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 Purchaser (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 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 the Purchaser 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,



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         without prejudice, however, to the rights of the Purchaser 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) The Purchaser's Right to Withdraw. The Purchaser
         shall have the right to withdraw his request for inclusion of his
         Registrable Securities in any registration statement pursuant to this
         Section 2.1 by giving written notice to the Company of his 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 Purchaser
         accepts 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
         that have requested securities to be included in such offering
         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 Purchaser.

                  2.2 Demand Registration.

                           (a) Request for Registration. Except as provided in
         Section 2.2(e) below, the Purchaser 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, 2005 the Purchaser
         shall have the right to require the Company to file a registration
         statement under the Securities Act covering the Registrable Securities,
         by delivering a written request therefor to the Company specifying the
         Registrable Securities to be included in such registration by the
         Purchaser 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
         best efforts to effect such registration under the Securities Act
         (including, without limitation, by means of a shelf



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         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 the Purchaser to request the Demand Registration pursuant to Section
         2.2(a) are subject to the following limitations: (i) the Purchaser
         shall not be entitled to a Demand Registration Request if the Purchaser
         has not converted the Note, or some portion of the Note, into a minimum
         of 133,334 shares of Common Stock, (ii) except as provided in Section
         2.2(e), in no event shall the Purchaser be entitled to more than one
         Demand Registration Request, (iii) if the request is made prior to
         December 31, 2002 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 (iv) if
         the Purchaser has participated in a Demand Registration in a 90 day
         period preceding the request. Notwithstanding anything in this Section
         2.2(c) to the contrary, 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 best 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 Purchaser.

                           (e) Underwriting Requirements. If the Purchaser
         intends to distribute the Registrable Securities by means of an
         underwriting, he shall so advise the Company as a part of his request
         made pursuant to Section 2.2(a). The underwriter will be selected by
         the Purchaser and shall be reasonably acceptable to the Company. All
         Persons, including the Purchaser, proposing to distribute their Common
         Stock through such underwriting shall (together with the Company as
         provided in Section 2.7) enter into an underwriting agreement in
         customary form with the underwriter or underwriters selected for such
         underwriting. Notwithstanding any other provisions of this Section 2.2,
         if the underwriter advises the Purchaser 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 the Purchaser and other Persons whose Common Stock 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 owned by the Purchaser and the other Selling
         Shareholders; provided, however, that the number of shares of
         Registrable Securities or Common Stock of the Selling Shareholders the
         Company has agreed may be included in the offering shall not be reduced
         unless all other securities of the Company,



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         for its own account, are first entirely excluded from the underwriting
         and registration. In the event that notice is received from the
         underwriter that the number of shares to be underwritten should be
         limited, and as a result of such limitation Purchaser will continue to
         hold 133,334 or more shares of 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 best 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 Purchaser 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 Purchaser 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;

                           (c) furnish, without charge, to the Purchaser 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 the Purchaser and underwriter may reasonably request in
         order to facilitate the public sale or other disposition of the
         Registrable



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         Securities owned by the Purchaser (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
         the Purchaser 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 the
         Purchaser 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 the Purchaser 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
         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 Purchaser shall reasonably request in order to expedite or
         facilitate the disposition of such Registrable Securities. The Persons
         who are holders of the Registrable Securities which are to be
         distributed by



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         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 Persons 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 or letter from (i) the Company's
         counsel or (ii) an independent accountant of the Company is delivered
         to any underwriters in the offering, the Company shall furnish to the
         Purchaser, a copy of such opinion and letter addressed to the
         Purchaser;

                           (h) delivery promptly to the Purchaser 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 the Purchaser, 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 the Purchaser 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 the Purchaser, 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 Purchaser 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 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.



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                  2.4 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 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.

                           (c) Notwithstanding the foregoing, (x) the provisions
         of this Section 2.4 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, the Purchaser shall pay all underwriting
         discounts and commissions and any transfer taxes, if any, attributable
         to the sale of his Registrable Securities, pro rata with respect to
         payments of discounts and commissions in accordance with the number of
         shares sold in the offering by the Purchaser, 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).

                  2.5 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 the Purchaser that the Purchaser
shall furnish to the Company such information regarding himself, the Registrable
Securities held by him, and the intended method of disposition of such
securities as shall be required to effect the registration of the Purchaser's
Registrable Securities.

                  2.6 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, the Purchaser, its
         agents and representatives 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



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         any settlement effected with the Company's consent, which consent shall
         not be unreasonably withheld or delayed) to which 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 Company shall not be liable to 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 Purchaser will, and hereby does, 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 Purchaser'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 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 Purchaser 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



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<PAGE>

         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 unless it is
         contained in the written information furnished to the Company by or on
         behalf of the Purchaser specifically for use therein; provided,
         further, that the obligation to indemnify will be limited to the amount
         of proceeds received by the Purchaser 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
         the Purchaser.

                           (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 2.6, 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 2.6, 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



                                       10
<PAGE>

         include a statement as to or an admission of fault, culpability or a
         failure to act, by or on behalf of any indemnified party.

                           (d) If for any reason the foregoing indemnity is
         unavailable or is insufficient to hold harmless an indemnified party
         under Section 2.6 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 2.6(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 2.6(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.

         2.7 Underwritten Offerings. If requested by the underwriters for any
underwritten offering by the Purchaser of Registrable Securities pursuant to a
registration requested under Article 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 Purchaser 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 Purchaser 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 and 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;



                                       11
<PAGE>

                           (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 the Purchaser owns any Registrable
         Securities, furnish to the Purchaser 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. General.

         4.1 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.

         4.2 Notices. All notices, elections, request, demands or other
communications required hereunder shall be in writing and shall be deemed given
when sent by facsimile (receipt confirmed electronically), delivered personally,
within three days after mailing when mailed by certified or registered mail,
return receipt requested or within one day after sent by a reputable overnight
carrier, 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: Michael Smith
                                                c/o The Kaitar Foundation
                                                1660 Lincoln St., Suite 1420
                                                Denver, CO 80264
                                                Fax: (303) 832-9015


                           With a Copy to:      Brownstein Hyatt & Farber, P.C.
                                                410 17th Street, Suite 2200
                                                Denver, CO 80202-4437
                                                Attention: Steven C. Demby, Esq.
                                                Telephone: (303) 223-1119
                                                Facsimile: (303) 223-0919

                  (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



                                       12
<PAGE>

                           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.

                                                and

                                                Patton Boggs LLP
                                                1660 Lincoln Street, Suite 1900
                                                Denver, Colorado 80202
                                                Telephone: (303) 830-1776
                                                Facsimile: (303) 894-9239
                                                Attention: Robert M. Bearman,
                                                           Esq.

         4.3 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. The right
         to cause the Company to register the Registrable Securities may be
         assigned or otherwise conveyed by the Purchaser to any transferee who
         acquires the Registrable Securities, Note or Warrant pursuant to and in
         accordance with the documents that govern such securities; provided,
         however, that Purchaser provides the Company written notice of such
         transfer, stating the name and address of said transferee and said
         transferee's agreement to be bound by the provisions of this Agreement
         and if such right is assigned or conveyed to more than one person, the
         holder of a majority of the Registrable Securities shall be entitled to
         effect or cause the Demand Registration Request.

                           (b) This Agreement as well as the Note and Warrant
         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.



                                       13
<PAGE>

                           (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.

                           (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]



                                       14
<PAGE>

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


                                       ASPENBIO, INC.


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


                                       -----------------------------------------
                                       MICHAEL S. SMITH

