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                                                                EXHIBIT 10.19(c)

                            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 Cambridge Holdings, Ltd., a Colorado corporation (the
"Purchaser").

                                    RECITALS

     A. On the date hereof, the Purchaser acquired from the Company a note in
the principal amount of $200,000 (the "Note") and a warrant to purchase up to
100,000 shares of Common Stock (the "Warrant") in consideration of the
Purchaser's agreement to advance funds on behalf of the Company in connection
with a Limited Continuing Guaranty, made by the Purchaser to the First Bank of
Tech Center in connection with the Company's construction loan obtained from the
Bank.

     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.

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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) shares of Common Stock issuable or
issued upon exercise of the Warrant, (ii) any shares of Common Stock Purchaser
now owns or hereinafter acquires, 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) 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

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     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,
     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

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     "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 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

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     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, for its own account, are first entirely excluded from the
     underwriting and registration.

          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

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     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 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;

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               (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 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

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               (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 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.

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          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 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

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     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 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

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     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.

               (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.

                                       11
<PAGE>

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;

               (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:    Cambridge Holdings, Ltd.
                                           106 South University, #14
                                           Denver, CO 80209
                                           Fax: (303) 722-4011
                                           Attention: Gregory Pusey, President

               (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,
     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:
                                              ----------------------------------


                                       -----------------------------------------
                                       CAMBRIDGE HOLDINGS, LTD.

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

                                       15

