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                                                                     EXHIBIT 4.2

                        Primecore Mortgage Trust, Inc.
                     Founder's Registration Rights Agreement

     This Founder's Registration Rights Agreement is made and entered into as of
March 30, 1999, by and among Primecore Mortgage Trust, Inc., a Maryland
corporation, and Michael Heren, Susan Fox and Michael Rider, holders of shares
of the Company's Common stock.

     In consideration of the mutual agreements contained herein and for other
good and valuable consideration, the receipt and sufficiency of which is hereby
acknowledged, the parties hereto, intending to be legally bound, hereby agree as
follows:

Section 1. Definitions
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     In this agreement, the following terms shall have the following meanings:

     "affiliate" of a specified person shall mean any other person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified person. For purposes of this definition, "control,"
when used with respect to any person means the power to direct the management
and policies of such person, directly or indirectly, whether through the
ownership of voting securities, by contract or otherwise; and the terms
"controlling" and "controlled" have meanings correlative to the foregoing.

     "common stock" shall mean the Company's common stock, par value $0.01 per
share.

      "Company" shall mean Primecore Mortgage Trust, Inc., a Maryland
corporation, and any successor.

     "Exchange Act" shall mean the Securities Exchange Act of 1934, as amended,
and the rules and regulations of the SEC promulgated thereunder.

     "holders" shall be as defined in section 2(b) hereof.

     "NASD" means National Association of Securities Dealers, Inc.

     "NASDAQ/NMS shall mean Nasdaq National Market.

     "person" shall mean an individual, trustee, corporation, partnership,
limited liability company, joint stock company, trust, unincorporated
association, union, business association, firm or other entity.

     "preferred stock" shall mean Primecore Mortgage's Class A Convertible
Preferred Stock, par value $0.01 per share.

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     "proceeding" shall mean an action, claim, suit or proceeding, including,
without limitation, an investigation or partial proceeding, such as a
deposition, where commenced or threatened.

     "prospectus" shall mean the prospectus included in any registration
statement, including, without limitation, a prospectus that discloses
information previously omitted from a prospectus filed as part of an effective
registration statement in reliance upon Rule 430A promulgated under the
Securities Act, as amended or supplemented by any prospectus supplement, with
respect to the terms of the offering of any portion of the registrable
securities covered by such registration statement, and all other amendments and
supplements to that prospectus, including post-effective amendments, and all
material incorporated by reference or deemed to be incorporated by reference in
that prospectus.

     "registrable securities" shall mean the shares of common stock held by such
holder on the date of this agreement until such time as such shares of common
stock shall have been effectively registered under the Securities Act and
disposed of in accordance with the registration statement covering such shares,
or are otherwise freely transferable by the holder without requirement of
registration under the Securities Act.

     "registration statement" shall mean any registration statement of the
Company that covers any of the registrable securities pursuant to the provisions
of this agreement, including the prospectus, amendments and supplements of such
registration statement and all exhibits and all material incorporated by
reference or deemed to be incorporated by reference in such registration
statement.

     "Rule 144" shall mean Rule 144 under the Securities Act, as such rule may
be amended from time to time, or any similar rule or regulation hereafter
adopted by the SEC.

     "SEC" shall mean the United States Securities and Exchange Commission.

     "shelf registration statement" shall mean the registration statement
covering sales of securities of the Company by purchasers of the preferred stock
in the Company's private placement first closing in April 1999.

     "underwriter" shall mean any underwriter, placement agent, selling broker,
dealer manager, qualified independent underwriter or similar securities industry
professional.

     "underwritten registration or underwritten offering" shall mean a
registration in which securities of the Company are sold to an underwriter for
re-offering to the public.

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Section 2. Securities Subject to this Agreement

     (a)  Registrable securities. The securities entitled to the benefits of
          ----------------------
this agreement are the registrable securities.

     (b)  Holders of Registrable securities. A person is deemed to be a holder
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of registrable securities whenever such person owns registrable securities.

Section 3. Piggyback Registration

     (a)  Right to Piggyback. Following the effective date of the shelf
          ------------------
registration statement, if the Company proposes to file a registration statement
under the Securities Act with respect to a firm commitment underwritten public
offering of common stock, other than a registration statement (1) on Form S-4,
Form S-8 or any successor forms or (2) filed solely in connection with an
exchange offer or any employee benefit or dividend reinvestment plan, whether or
not for its own account, then the Company shall give written notice of such
proposed filing to the holders of registrable securities at least fifteen days
before the anticipated filing date, the "piggyback notice". The piggyback notice
shall offer such holder the opportunity to include in such underwritten offering
such amount of registrable securities as such holder may request, a "piggyback
underwritten offering." Subject to section 3(b) hereof, the Company shall
include in each such piggyback underwritten offering all registrable securities
with respect to which the Company has received written requests for inclusion
therein within ten days after notice has been given to the applicable holder,
which request shall specify the intended method of distribution. The holders of
registrable securities shall be permitted to withdraw all or part of the
registrable securities from a piggyback underwritten offering at any time prior
to the effective date of such piggyback underwritten offering.

     (b)  Priority on Piggyback Underwritten offerings. The Company shall cause
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the managing underwriter or underwriters of a proposed underwritten offering to
permit Holders of registrable securities to include all such registrable
securities requested to be included in the piggyback underwritten offering on
the same terms and conditions as any other shares of common stock, if any, of
the Company included therein. Notwithstanding the foregoing, if the managing
underwriter or underwriters of such piggyback underwritten offering have
informed the Company in writing that it is their opinion that the total amount
of securities that such holders, the Company and any other persons having rights
to participate in such offering, intended to include in such offering is such as
to materially and adversely affect the success of such offering, then the common
stock to be offered in the piggyback underwritten offering shall be the amount
recommended by such managing underwriter or underwriters and the common stock to
be included in such piggyback underwritten offering shall be included in the
following order of priority: (1) for the account of the Company, as many shares
as the Company may desire or be permitted to sell at such time, the "company
allotment"; (2) for the account of all such other persons, other than the
Company, as many shares as such persons may desire to sell at such time, the
"other holders allotment"; and (3) the remaining capacity, if any, for the
account of the holders, the "holders allotment", to be divided among such

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holders pro rata in proportion to the respective dollar amounts of such
securities requested to be registered

Section 4. Hold-Back Agreements

     (a)  Restrictions on Public Sale by Holders of Registrable securities. Each
          ----------------------------------------------------------------
holder of registrable securities agrees, in connection with any underwritten
offering of securities by the Company and in connection with any other
underwritten offering, until such time as there are no remaining registrable
securities, if requested pursuant to a timely written notice by the Company or
the managing underwriter or underwriters in an underwritten offering, not to
effect any public sale or distribution of any of its registrable securities,
including a sale pursuant to Rule 144, except as part of such underwritten
offering, during the period beginning ten days before, and ending ninety days
after, the closing date of such underwritten offering, unless a shorter time
period is agreed to by the managing underwriter or underwriters.

     (b)  Restrictions on Public Sale by the Company. The Company agrees that
          ------------------------------------------
without the written consent of the managing underwriter or underwriters in an
underwritten offering of registrable securities as described in section 3
hereof, it will not effect any public or private sale or distribution of its
equity securities, including a sale pursuant to Regulation D under the
Securities Act, during the ten day period before, and the ninety day period
beginning on, the closing date of each such underwritten offering, unless a
shorter time period is agreed to by the managing underwriter or underwriters,
except:

     .    as part of such Underwritten Offering;

     .    pursuant to registrations on Form S-4 or Form S-8 or any successor
form to such forms or pursuant to any unregistered offering to the Company's
employees or directors, or to employees of its subsidiaries, pursuant to any
employee benefit plan as defined in Rule 405 under the Securities Act or
dividend reinvestment plan;

     .    pursuant to the conversion of preferred stock or exercise of warrants;

     .    in connection with an exchange offer; or

     .    in connection with the acquisition of assets by the Company or its
subsidiaries).

Section 5. Registration Procedures

     In connection with the Company's registration obligations pursuant to
section 3 hereof, the Company shall effect such registration(s) to permit the
sale of such registrable securities in accordance with the intended method or
methods of disposition thereof, as follows:

     (a)  Prepare and file with the SEC a registration statement or registration
statements on such form which shall be available for the sale of registrable
securities in accordance with the intended method or methods of distribution
thereof, and use its best efforts to cause such

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registration statement to become effective and to remain effective as provided
herein; provided, however, that before filing a registration statement or
prospectus or any amendments or supplements thereof, including documents that
would be incorporated or deemed to be incorporated therein by reference, the
Company shall notify the holders of the registrable securities covered by such
registration statement, their counsel and managing underwriters, if any, of its
intention to file such documents, and upon request shall furnish to such parties
so requesting copies of all such documents proposed to be filed, which documents
will be subject to the review by such holders, their counsel and such
underwriters, if any, provided, however, that the Company shall not be required
to deliver to such holders a copy of any such document that has not been
materially changed from a copy of such document that was previously delivered to
such holders.

     (b)  Prepare and file with the SEC such amendments to each registration
statement as may be necessary to cause such registration statement to become
effective with respect to the disposition of all securities covered by such
registration statement; and cause the related prospectus to be supplemented by
any required prospectus supplement, and as so supplemented to be filed pursuant
to Rule 424, or any similar provisions then in force, under the Securities Act.

     (c)  Notify the selling holders of registrable securities, their counsel
and the managing underwriters, if any, promptly, and if requested by any such
person, confirm such notice in writing:

          (1)  when a registration statement or any amendment thereto has been
     filed, and, with respect to a registration statement, when the same has
     become effective;

          (2)  of any request by the SEC or any other Federal or state
     governmental authority for amendments or supplements to a registration
     statement or related prospectus or for additional information, provided,
     that the Company shall not be required to notify the holders or their
     counsel of all "comment" letters received by the Company from the SEC or to
     deliver copies of the Company's responses to the holders or their counsel
     unless such letters request information from or about the holders;

          (3)  of the issuance by the SEC of any stop order suspending the
     effectiveness of a registration statement or the initiation of any
     proceedings for that purpose;

          (4)  if at any time the representations and warranties of the Company
     contained in any agreement, including any underwriting agreement,
     contemplated by section 5(n) below ceases to be true and correct;

          (5)  of the receipt by the Company of any notification with respect to
     the suspension of the qualification or exemption from qualification of any
     of the registrable securities for sale in any jurisdiction, or the
     initiation or threatening of any proceeding for such purpose; and

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          (6)  of the happening of any event that makes any statement made in
     such registration statement or related prospectus or any document
     incorporated or deemed to be incorporated therein by reference untrue in
     any material respect or that requires the making of any changes in such
     registration statement, prospectus or documents so that, in the case of the
     registration statement, it will not contain any untrue statement of a
     material fact or omit to state any material fact necessary in order to make
     the statements therein, in light of the circumstances under which they were
     made, not misleading.

     (d)  Use its best efforts to obtain the withdrawal of any order suspending
the effectiveness of a registration statement, or the lifting of any suspension
of the qualification, or exemption from qualification, of any of the registrable
securities for sale in any jurisdiction.

     (e)  If requested by managing underwriters, if any, or the holders of a
majority of the then outstanding registrable securities being sold in connection
with an underwritten offering, promptly include in a prospectus supplement or
post-effective amendment such information as the managing underwriters, if any,
and such holders may reasonably request in order to permit the intended method
of distribution of such securities and make all required filings of such
prospectus supplement or such post-effective amendment as soon as practicable
after the Company has received such request; provided however, that the Company
shall not be required to take any actions under this section 5(e) that are not,
in the opinion of counsel for the Company, in compliance with applicable law.

     (f)  Furnish to a selling holder of registrable securities, their counsel
and each managing underwriter, if any, without charge, at least one conformed
copy of the registration statement and each post-effective amendment thereto,
including financial statements, but excluding schedules, all documents
incorporated or deemed to be incorporated therein by reference, and all
exhibits, unless requested in writing by such holder, counsel or underwriter.

     (g)  Deliver to each selling holder of registrable securities, their
counsel, and the underwriters, if any, without charge, as many copies of the
prospectus or prospectuses, including each form of prospectus, and each
amendment or supplement thereto as such persons may reasonably request in
connection with the distribution of the registrable securities; and the Company
hereby consents to the use of such prospectus and each amendment or supplement
thereto by each of the selling holders of registrable securities and the
underwriters, if any, in connection with the offering and sale of the
registrable securities covered by such prospectus and any such amendment or
supplement thereto.

     (h)  Use its best efforts to register or qualify, or obtain an exemption
therefrom, or cooperate with the selling holders of registrable securities, the
underwriters, if any, and their respective counsel in connection with the
registration or qualification, or exemption from such registration or
qualification, of such registrable securities for offer and sale under the
securities or "Blue Sky" laws of such jurisdictions within the United States as
any seller, or underwriter, reasonably requests in writing and to keep such
registration or qualification, or exemption therefrom, effective during the
period such registration statement is required to be

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kept effective; provided, however, that the Company will not be required to (A)
qualify generally to do business in any jurisdiction where it is not then so
qualified or (B) take any action that would subject it to general service of
process or to taxation in any such jurisdiction where it is not then so subject.

     (i)  Cooperate with the selling holders of registrable securities and the
managing underwriters, if any, to facilitate the timely preparation and delivery
of certificates representing registrable securities to be sold, which
certificates shall be in a form eligible for deposit with The Depository Trust
Company; and enable such registrable securities to be in such denominations and
registered in such names as the managing underwriters, if any, or holders may
request at least two business days before any sale of registrable securities in
a firm commitment public offering, or in any other such sale within ten business
days.

     (j)  Use its best efforts to cause the registrable securities covered by
the registration statement to be registered with or approved by such other
governmental agencies or authorities within the United States, except as may be
required solely as a consequence of the nature of such selling holder's
business, in which case the Company will cooperate in all best respects with the
filing of such registration statement and the granting of such approvals as may
be necessary to enable the seller or sellers thereof or the underwriters, if
any, to consummate the disposition of such registrable securities.

     (k)  Upon the occurrence of any event contemplated by section 5(c)(6)
above, prepare a supplement or post-effective amendment to the registration
statement or a supplement to the related prospectus or any document incorporated
or deemed to be incorporated therein by reference, or file any other required
document so that, as thereafter delivered to the purchasers of the registrable
securities being sold thereunder, such prospectus will not contain 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 light of the
circumstances under which they were made, not misleading.

     (l)  Prior to the effective date of the registration statement relating to
the registrable securities, provide a CUSIP number for the registrable
securities.

     (m)  Use its best efforts to cause all registrable securities covered by
such registration statement to be authorized to be quoted on the NASDAQ/NMS or
listed on a national securities exchange upon effectiveness of the registration
statement.

     (n)  Enter into such agreements, including an underwriting agreement in
form, scope and substance as is customary in underwritten offerings and take all
such other actions reasonably requested by the holders of a majority of the
registrable securities being sold in connection therewith, including those
reasonably requested by the managing underwriters, if any, in order to expedite
or facilitate the disposition of such registrable securities, and in such
connection, whether or not an underwriting agreement is entered into and whether
or not the registration is an underwritten registration:

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          (1)  make such representations and warranties to the holders of such
     registrable securities and the underwriters, if any, with respect to the
     business of the Company and its subsidiaries, and the registration
     statement, prospectus and documents, if any, incorporated or deemed to be
     incorporated by reference therein, in each case, in form, substance and
     scope as are customarily made by users to underwriters in underwritten
     offerings, and if true, confirm the same if and when requested;

          (2)  use its reasonable efforts to obtain opinions of counsel to the
     Company and updates thereof, which counsel and opinions in form, scope and
     substance, shall be reasonably satisfactory to the managing underwriters,
     if any, and counsel to the holders of the registrable securities being
     sold, addressed to each selling holder of registrable securities and each
     of the underwriters, if any, covering the matters customarily covered in
     opinions requested in underwritten offerings and such other matters as may
     be reasonably requested by such counsel and underwriters;

          (3)  use its reasonable efforts to obtain "cold comfort" letters and
     updates thereof from the independent certified public accountants of the
     Company and, if necessary, any other independent certified public
     accountants of any subsidiary of the Company or of any business acquired by
     the Company for which financial statements and financial data are, or are
     required to be, included in the registration statement, addressed to each
     selling holder of registrable securities, unless such accountants shall be
     prohibited from so addressing such letters by applicable standards of the
     accounting profession, and each of the underwriters, if any, such letters
     to be in customary form and covering matters of the type customarily
     covered in "cold comfort" letters in connection with underwritten
     offerings;

          (4)  if an underwriting agreement is entered into, the same shall
     contain indemnification provisions and procedures substantially to the
     effect set forth in section 7 hereof with respect to all parties to be
     indemnified pursuant to said section; and

          (5)  deliver such documents and certificates as may be reasonably
     requested by the holders of a majority of the registrable securities being
     sold, their counsel and the managing underwriters, if any, to evidence the
     continued validity of the representations and warranties made pursuant to
     section 5(n)(1) above and to evidence compliance with any customary
     conditions contained in the underwriting agreement or other agreement
     entered into by the Company. The above shall be done at each closing under
     such underwriting or similar agreement, or as and to the extent required
     thereunder.

     (o)  Make available for inspection by a representative of the holders of
registrable securities being sold, any underwriter participating in any such
disposition of registrable securities, if any, and any attorney or accountant
retained by such selling holders or underwriter, at the offices where normally
kept, during reasonable business hours, all financial and other records,
pertinent corporate documents and properties of the Company and its
subsidiaries, and cause the officers, directors and employees of the Company and
its

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subsidiaries to supply all information in each case reasonably requested by
any such representative, underwriter, attorney or accountant in connection with
such registration statement; provided, however, that any information that is
designated by the Company in writing as confidential at the time of delivery of
such information shall be kept confidential by such persons unless:

          (1)  disclosure of such information is required by court or
     administrative order;

          (2)  disclosure of such information, in the opinion of counsel to such
     person, is required by law; or

          (3)  such information becomes generally available to the public other
     than as a result of a disclosure or failure to safeguard by such person.
     Without limiting the foregoing, no such information shall be used by such
     person as the basis for any market transactions in securities by the
     Company or its subsidiaries in violation of law.

     (p)  Comply with all applicable rules and regulations of the SEC and make
generally available to its securities holders earning statements satisfying the
provisions of Section 11(a) of the Securities Act and Rule 158 thereunder, or
any similar rule promulgated under the Securities Act, no later than forty-five
days after the end of any twelve month period, or ninety days after the end of
any twelve month period if such period is a fiscal year:

          (1)  commencing at the end of any fiscal quarter in which registrable
     securities are sold to underwriters in a firm commitment or best efforts
     underwritten offering; and

          (2)  if not sold to underwriters in such an offering, commencing on
     the first day of the first fiscal quarter of the Company after the
     effective date of the registration statement, which statements shall cover
     said twelve month periods.

     (q)  Make every reasonable effort to obtain the withdrawal of any order
suspending the effectiveness of the registration statement at the earliest
possible moment.

     (r)  Cooperate and assist in any filings required to be made with the NASD
and in the performance of any due diligence investigation by any underwriter,
including any "qualified independent underwriter" that is required to be
retained in accordance with the rules and regulations of the NASD.

     The Company may require each seller of registrable securities as to which
any registration is being effected to furnish to the Company such information
regarding such seller and the distribution of such registrable securities as the
Company may, from time to time, reasonably request in writing and the Company
may exclude from such registration the registrable securities of any seller who
unreasonably fails to furnish such information within a reasonable time after
receiving such request.

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     Each holder of registrable securities agrees by acquisition of such
registrable securities that, upon receipt of any notice from the Company of the
happening of any event of the kind described in Section 5(c)(2), (3), (5) or (6)
hereof, such holder will forthwith discontinue disposition of such registrable
securities covered by such registration statement or prospectus until such
holder's receipt of the copies of the supplemented or amended prospectus
contemplated by section 5(k) hereof, or until it is advised in writing by the
Company that the use of applicable prospectus may be resumed, and has received
copies of any additional or supplemental filings that are incorporated or deemed
to be incorporated by reference in such prospectus.

Section 6. Registration Expenses

     (a)  All expenses incident to the Company's performance of or compliance
with this agreement will be borne by the Company, regardless whether a
registration statement filed pursuant to section 3 herein becomes effective,
including without limitation:

          (1)  all registration and filing fees and expenses associated with any
     SEC filing;

          (2)  fees and expenses of compliance with federal securities or state
     blue sky laws, including fees and disbursements of counsel for the
     underwriters or selling holders in connection with the Blue Sky
     qualifications of the registrable securities pursuant to 5(h) herein;

          (3)  expenses of printing, including, without limitation, expenses of
     printing or engraving certificates for the registrable securities in a form
     eligible for deposit with The Depository Trust Company and of printing
     prospectuses, messenger and delivery services and telephone;

          (4)  reasonable fees and disbursements of counsel for the Company and
     for the holders of the registrable securities, subject to the provisions of
     section 4(b) hereof;

          (5)  fees and disbursements of all independent certified public
     accountants of the Company, including the expenses of any special audit and
     "cold comfort" letters required by or incident to such performance;

          (6)  fees and expenses associated with any NASD filing required to be
     made in connection with a registration statement, including, if applicable,
     the fees and expenses of any "qualified independent underwriter" (and its
     counsel) that is required to be retained in accordance with the rules and
     regulations of the NASD; and

          (7)  fees and expenses of listing the registrable securities on any
     securities exchange or quotation system in accordance with section 5(m)
     hereof. All such expenses being herein called "registration expenses."

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     The Company will, in any event, bear its internal expenses, including,
without limitation, all salaries and expenses of its officers and employees
performing legal or accounting duties, the expense of any annual audit, rating
agency fees and the fees and expenses of any person, including special experts,
retained by the Company. The holders of the registrable securities shall bear
the expense of any broker's commission or underwriters' discount or commission.

     (b)  In connection with an underwritten offering pursuant to the
registration statement, the Company will reimburse the holders of registrable
securities being registered pursuant to such registration statement for the fees
and disbursements of not more than one counsel chosen by a majority of the
holders of the for the fees and disbursements of not more than one counsel
chosen by a majority of the holders of the registrable securities to be included
in the registration statement; provided, however, that in the case of an
underwritten offering which includes shares of common stock, such counsel shall
be chosen by the holders of a majority of the shares of common stock to be
included in such underwritten offering. Notwithstanding the provisions of this
section 6, each holder of registrable securities shall pay all registration
expenses to the extent required by applicable law.

Section 7. Indemnification

     (a)  The Company agrees to indemnify and hold harmless each holder,
referred to as an "indemnified holder", and each underwriter participating in an
underwritten offering, referred to as an "indemnified underwriter", and each
person that controls each indemnified holder or indemnified underwriter within
the meaning of Section 15 of the Securities Act or Section 20 of the Exchange
Act, and agents, employees, officers and directors or any such controlling
person of any indemnified holder or indemnified underwriter from and against any
and all losses, claims, damages, judgments, liabilities and expenses, including
the reasonable fees and expenses of counsel and other expenses in connection
with investigating, defending or setting any such action or claim, as they are
incurred arising out of or based upon an untrue statement or alleged untrue
statement of a material fact contained in any registration statement or the
prospectus, as amended or supplemented if the Company shall have furnished any
amendments or supplements thereto, or any preliminary prospectus or arising out
of or based upon any omission or alleged omission to state therein a material
fact required to be stated therein or necessary to make the statements therein
not misleading, except (1) the Company shall not be liable to any indemnified
holder or indemnified underwriter in any such case insofar as such losses,
claims, damages, judgments, liabilities or expenses arise out of, or are based
upon, any such untrue statement or omission or alleged untrue statement or
omission based upon information relating to such indemnified holder or
indemnified underwriter furnished in writing by such indemnified holder or
indemnified underwriter to the Company expressly for use therein, and (2) the
Company shall not be liable to any indemnified holder or indemnified underwriter
under the indemnity agreement in this section 7(a) with respect to any
preliminary prospectus to the extent that any such loss, claim, damage,
judgment, liability or expense results solely from the fact that any indemnified
holder or indemnified underwriter sold registrable securities to a person to
whom there was not sent or give, at or prior to the written confirmation of such
sale, a copy of the prospectus as then amended or supplemented,

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if the Company has previously furnished sufficient copies thereof to the
indemnified holder or indemnified underwriter.

     (b)  If any action or proceeding, including any governmental or regularly
investigation or proceeding, shall be brought or asserted against any
indemnified holder or indemnified underwriter with respect to which indemnity
may be sought against the Company pursuant to section 7(a) such indemnified
holder or indemnified underwriter shall promptly notify the Company in writing,
and the Company shall have the right to assume the defense thereof, including
the employment of counsel reasonable satisfactory of such indemnified holder or
indemnified underwriter and payment of all fees and expenses; provided, however,
that the omission so to notify the Company shall not relieve the Company from
any liability that they may have to any indemnified holder or indemnified
underwriter, except to the extent that the Company is materially prejudiced or
otherwise forfeits substantive rights or defenses by reason of such failure. An
indemnified holder or indemnified underwriter shall have the right to employ
separate counsel in any such action or proceeding and to participate in the
defense thereof, but the fees and expenses of such counsel shall be at the
expense of such indemnified holder or indemnified underwriter unless:

          (1)  the Company agrees in writing to pay such fees and expenses;

          (2)  the Company has failed to assume the defense and employ counsel
     satisfactory to the indemnified holder or indemnified underwriter; or

          (3)  the named parties to any such action or proceeding, including any
     impleaded parties, include both the indemnified holder or indemnified
     underwriter and the Company and such indemnified holder or indemnified
     underwriter shall have been advised in writing by its counsel that
     representation of them and the Company by the same counsel would be
     inappropriate under applicable standards of professional conduct, whether
     or not such representation has been proposed, due to actual or potential
     differing interests between them, in which case the Company shall not have
     the right to assume the defense of such action on behalf of such
     indemnified holder or indemnified underwriter.

     It is understood that the Company shall not, in connection with any one
such action or separate but substantially similar or related actions in the same
jurisdiction arising out of the same general allegations or circumstances, be
liable for the fees and expenses of more than one separate firm of attorneys, in
addition to any local counsel, at any time for such indemnified holders or
indemnified underwriters, which firm shall be designated in writing by the
majority of holders of the registrable securities on behalf of the holders of
all of the registrable securities, and that all such fees and expenses shall be
reimbursed as they are incurred. The Company shall not be liable for any
settlement of any such action effected without the written consent of the
Company, but if settled with the written consent of the Company, or if there is
a final judgment with respect thereto, the Company agrees to indemnify and hold
harmless each indemnified holder or indemnified underwriter from and against any
loss or liability by reason of such settlement or judgment. The Company shall
not,

                                       12
<PAGE>

without the prior written consent of each indemnified holder or indemnified
underwriter affected thereby, effect any settlement of any pending or threatened
proceeding in which such indemnified holder or indemnified underwriter has
sought indemnity hereunder, unless such settlement includes an unconditional
release of such indemnified holder or indemnified underwriter from all liability
arising out of such action, claim, litigation or proceeding.

     (c)  Each holder and underwriter agrees to indemnify and hold harmless the
Company, its directors, its officers who sign the registration statement and any
person controlling the Company within the meaning of Section 15 of the
Securities Act or Section 20 of the Exchange Act, collectively referred to as
the "company indemnified parties", to the extent as the foregoing indemnity from
the Company to any indemnified holder or indemnified underwriter, but only with
respect to information relating to each holder or underwriter furnished to the
Company in writing by each holder or underwriter, respectively, expressly for
use in the registration statement, prospectus, or any amendment of supplement
thereto, or any preliminary prospectus. In case any action shall be brought
against any Company indemnified party based on the registration statement,
prospectus, or any amendment or supplement thereto, or any preliminary
prospectus and in respect of which indemnification may be sought against each
holder and underwriter pursuant to this section 7(c), each holder and
underwriter shall have the rights and duties given to the Company by section
7(a), except that if the Company shall have assumed the defense thereof, each
holder and underwriter may, but shall not be required to, employ separate
counsel therein and participate in the defense thereof and the fees and expenses
of such counsel shall be at the expense of the holder or underwriter, and the
Company indemnified parties shall have the rights and duties given to the
indemnified holders or indemnified underwriters by section 7(b).

     (c)  If the indemnification provided for in this section 7 is unavailable
to any party entitled to indemnification pursuant to section 7(a) or (c), then
each indemnifying party, in lieu of indemnifying such indemnified party, shall
contribute to the amount paid or payable by such indemnified party as a result
of such losses, claims, damages, judgments, liabilities and expenses:

          (1)  in such proportion as is appropriate to reflect the relative
     benefits received by the Company on the one hand, and each indemnified
     holder or indemnified underwriter on the other, from the offering of the
     registrable securities; or

          (2)  if the allocation provided by clause (1) above is not permitted
     by applicable law, in such proportion as is appropriate to reflect not only
     the relative benefits referred to in clause (1) above but also the relative
     fault of the Company on the one hand and each indemnified holder or
     indemnified underwriter on the other in connection with the statement or
     omissions which resulted in such losses, claims, damages, judgments,
     liabilities or expenses, as well as any other relevant equitable
     considerations. The relative benefits received by the Company on the one
     hand and each indemnified holder or indemnified underwriter on the other
     shall be deemed to be in the same proportions as the total net proceeds
     from the offering, before deducting expenses, received by the Company bear
     to the total net discounts and commissions

                                       13
<PAGE>

     received by each indemnified holder or indemnified underwriter, in each
     case as set forth in the table on the cover page of the prospectus. The
     relative fault of the Company on the one hand each indemnified holder or
     indemnified underwriter on the other 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 Company on the one hand or by each
     indemnified holder or indemnified underwriter on the other and the parties'
     relative intent, knowledge, access to information and opportunity to
     correct or prevent such statement or omission.

     (e)  The Company and each indemnified holder or indemnified underwriter
agree that it would not be just and equitable if contribution pursuant to
section 7(d) were determined by pro rata allocation or by any other method of
allocation that does not take account of the equitable considerations referred
to in section 7(d). The amount paid or payable by an indemnified party as a
result of the losses, claims, damages, liabilities or expenses referred to in
the immediately preceding paragraph shall be deemed to include, subject to the
limitations set forth above, any legal or other expenses reasonably incurred by
such indemnified party in connection with investigating or defending any such
action or claim. No person found guilty of fraudulent misrepresentation, within
the meaning of Section 11(f) of the Securities Act, shall be entitled to
contribution from any person who was not found guilty of such fraudulent
misrepresentation.

     (f)  The indemnity and contribution agreements contained in this section
7 are in addition to any liability that any indemnifying party may otherwise
have to any indemnified party.

Section 8. Participation in Underwritten Registrations

     No holder may participate in any underwritten offering hereunder unless
such holder (a) agrees to sell such holder's registrable securities on the basis
provided in any underwriting arrangements approved by the persons entitled
hereunder to approve such arrangements, (b) completes and executes all
questionnaires, powers of attorney, indemnities, underwriting agreements, hold-
back agreements and other documents required under the terms of such
underwriting arrangements, and (c) furnishes the Company in writing information
in accordance with the second to the last paragraph of section 5 and agrees to
indemnify and hold harmless the Company, its directors, its officers who sign
the registration statement and any person controlling the Company within the
meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act as
contemplated by section 7(c).

Section 9. Miscellaneous

     (a)  Remedies. Each holder of registrable securities, in addition to being
          --------
entitled to exercise all rights provided herein and granted by law, including
recovery of damages, will be entitled to specific performance of such holder's
rights under this agreement. The Company agrees that monetary damages would not
be adequate compensation for any loss incurred by

                                       14
<PAGE>

reason of a breach by it of the provisions of this agreement and hereby agrees
to waive the defense in any action for specific performance that a remedy at law
would be adequate.

     (b)  No Inconsistent Agreements. The Company will not on or after the date
          --------------------------
of this agreement enter into any agreement with respect to its securities that
is inconsistent with the rights granted to the holders of registrable securities
in this agreement or otherwise conflicts with the provisions hereof. The rights
granted to the holders of registrable securities hereunder do not in any way
conflict with and are not inconsistent with the rights granted to the holders of
the Company's securities under any other agreements.

     (c)  Amendments and Waivers. The provisions of this agreement, including
          ----------------------
the provisions of this sentence, may not be amended, modified or supplemented,
and waivers or consents to departures with the provisions hereof may not be
given unless the Company has obtained the written consent of a majority of the
holders of the registrable securities affected by such amendment, modification,
supplement, waiver or departure. Notwithstanding the foregoing, a waiver or
consent to departure from the provisions hereof that relates exclusively to the
rights of holders of registrable securities whose securities are being sold
pursuant to a registration statement and that does not directly or indirectly
affect the rights of other holders of registrable securities shall be valid only
with the written consent of holders of at least 66-2/3% of the registrable
securities being sold.

     (d)  Notices. All notices and other communications provided for or
          -------
permitted hereunder shall be made in writing by hand-delivery, first-class mail,
registered or certified, return receipt requested, telex, telecopier, or air
courier guaranteeing overnight delivery:

          (i)  if to a holder of registrable securities, at the most current
address given by such holder to the Company; and

          (ii) if to the Company, to

               Primecore Mortgage Trust, Inc.
               99 El Camino Real
               Menlo Park, CA 94025
               Attn:  Susan Fox, President
               Telephone:  (650) 328-3060
               Facsimile:  (650) 328-3066

               with a copy to:

               Tobin & Tobin
               500 Sansome Street, /8/th Floor
               San Francisco, CA 94111
               Attn:  Keith A. Kandarian
               Telephone:  (415) 433-1400
               Facsimile:  (415) 433-3883

                                       15
<PAGE>

     All such notices and communications shall be deemed to have been duly
given: at the time delivered by hand, if personally delivered; five business
days after being deposited in the mail, postage prepaid, if mailed; when
answered back, if telexed; when receipt acknowledged, if telecopied; and on the
next business day, if timely delivered to an air courier guaranteeing overnight
delivery.

     (e)  Successors and Assigns. This agreement shall inure to the benefit of
          ----------------------
and be binding upon the successors and assigns of each of the parties, including
without limitation and without the need for an express assignment, and
subsequent holders of registrable securities; provided, however, that this
agreement shall not inure to the benefit of or be binding upon a successor or
assign of a holder of registrable securities unless and to the extent such
successor or assign acquired registrable securities from such holder. If any
transferee of any holder shall acquire registrable securities, in any manner,
whether by operation of law or otherwise, such registrable securities shall be
held subject to all of the terms of this agreement and by taking and holding
such registrable securities such person shall be conclusively seemed to have
agreed to be bound by and to perform all of the terms and provisions of this
agreement and such person shall be entitled to receive the benefits hereof.

     (f)  Counterparts. This agreement may be executed in any number of
          ------------
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

     (g)  Headings. The headings of this agreement are for convenience of
          --------
reference only and shall not limit or otherwise affect the meaning hereof.

     (h)  Governing Law. This agreement shall be governed by and construed in
          -------------
accordance with the laws of the State of California, without regard to the
conflict of law rules thereof.

     (i)  Severability. In the event that any one or more of the provisions
          ------------
contained herein, or the application thereof in any circumstance, is held
invalid, illegal or unenforceable, the validity, legality and enforceability of
any such provision in every other respect and of the remaining provisions
contained herein shall not be affected or impaired thereby.

     (j)  Entire Agreement. This agreement is intended by the parties as a final
          ----------------
expression of their agreement and intended to be a complete and exclusive
statement of the agreement and understanding of the parties hereto in respect of
the subject matter contained herein. There are no restrictions, promises,
warranties or undertakings, other than referred to herein with respect to the
registration rights granted by the Company with respect to registrable
securities. This agreement supersedes all prior agreements and understandings
between the parties with respect to such subject matter.

                                       16
<PAGE>

     The parties have executed this agreement as of the date first above
written.

Company:                                Primecore Mortgage Trust, Inc.


                                        By  /s/ Susan Fox
                                           ---------------------------------
                                           Susan Fox, President


                                            /s/ Michael Heren
Holders:                                ------------------------------------
                                           Michael Heren

                                            /s/ Susan Fox
                                        ------------------------------------
                                          Susan Fox

                                            /s/ Michael Rider
                                        ------------------------------------
                                          Michael Rider

                                       17