AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

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                                                                     EXHIBIT 4.2

                          TRUBION PHARMACEUTICALS, INC.

                 AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                  JULY 13, 2004

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                                TABLE OF CONTENTS

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I.   GENERAL.............................................................     2
   1.1    Definitions....................................................     2

II.  REGISTRATION; RESTRICTIONS ON TRANSFER..............................     3
   2.1    Restrictions on Transfer.......................................     3
   2.2    Demand Registration............................................     5
   2.3    Piggyback Registrations........................................     7
   2.4    Form S-3 Registration..........................................     8
   2.5    Expenses of Registration.......................................     9
   2.6    Obligations of the Company.....................................    10
   2.7    Termination of Registration Rights.............................    13
   2.8    Delay of Registration; Furnishing Information..................    13
   2.9    Indemnification................................................    13
   2.10   Assignment of Registration Rights..............................    15
   2.11   Limitation on Subsequent Registration Rights...................    16
   2.12   "Market Stand-Off" Agreement; Agreement to Furnish
          Information....................................................    16
   2.13   Rule 144 Reporting.............................................    17

III. INFORMATION COVENANTS OF THE COMPANY................................    18
   3.1    Basic Financial Information and Reporting......................    18
   3.2    Inspection Rights..............................................    19
   3.3    Confidentiality of Records.....................................    19

IV.  RIGHTS OF PARTICIPATION.............................................    19
   4.1    Subsequent Offerings...........................................    19
   4.2    Exercise of Rights.............................................    20
   4.3    Issuance of Offered Securities to Other Persons................    20
   4.4    Termination of Rights of Participation.........................    20
   4.5    Transfer of Rights of Participation............................    20
   4.6    Offered Securities.............................................    20
   4.7    No Impairment..................................................    22
   4.8    Closing........................................................    22

V.   MISCELLANEOUS COVENANTS OF THE COMPANY..............................    22
   5.1    Reservation of Common Stock....................................    22
   5.2    Proprietary Information and Invention Agreement................    22
   5.3    Stock Compensation Approval....................................    23
   5.4    Right of First Refusal on Employee Stock.......................    23
   5.5    Use of Proceeds................................................    23
   5.6    Qualified Small Business Stock Status..........................    23
   5.7    Directors and Officers Indemnification.........................    23
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                                TABLE OF CONTENTS
                                   (CONTINUED)

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   5.8    Directors' and Officers' Insurance.............................    23
   5.9    Chief Executive Officer........................................    23
   5.10   Directors' Expenses............................................    24
   5.11   Termination of Covenants.......................................    24

VI.  MISCELLANEOUS.......................................................    24
   6.1    Governing Law..................................................    24
   6.2    Survival.......................................................    24
   6.3    Successors and Assigns.........................................    24
   6.4    Entire Agreement...............................................    24
   6.5    Amendment and Waiver...........................................    24
   6.6    Notices, Etc...................................................    25
   6.7    Delays or Omissions............................................    26
   6.8    Counterparts...................................................    26
   6.9    Telecopy Execution and Delivery................................    26
   6.10   Severability...................................................    26
   6.11   Attorneys' Fees................................................    26
   6.12   Aggregation of Stock...........................................    26
   6.13   Jurisdiction; Venue............................................    26
   6.14   Further Assurances.............................................    27
   6.15   Prior Rights Agreement.........................................    27
   6.16   Waiver.........................................................    27
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                          TRUBION PHARMACEUTICALS, INC.

                 AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

     This Amended and Restated Investor Rights Agreement (the "AGREEMENT") is
entered into as of the 13th day of July 2004, by and among Trubion
Pharmaceuticals, Inc., a Delaware corporation (the "COMPANY"), and the investors
set forth on EXHIBIT A hereto (collectively the "INVESTORS" and each
individually an "INVESTOR").

                                    RECITALS

     WHEREAS, the Company and certain of the Investors (the "SERIES B
INVESTORS") have entered into a Series B Preferred Stock Purchase Agreement (the
"PURCHASE AGREEMENT") of even date herewith pursuant to which the Company
desires to sell to such Investors and such Investors desire to purchase from the
Company shares of the Company's Series B Preferred Stock (the "SERIES B
PREFERRED").

     WHEREAS, a condition to the Series B Investors' obligations under the
Purchase Agreement is that the Company and the Investors enter into this
Agreement in order to provide (i) the Investors with certain rights to register
shares of the Company's Common Stock issuable upon conversion of the Series A
Preferred Stock of the Company (the "SERIES A PREFERRED," and together with the
Series B Preferred, the "PREFERRED STOCK") and the Series B Preferred held by
the Investors, and certain rights to receive or inspect information pertaining
to the Company, and (ii) the Participating Investors (as defined herein) a right
of first offer with respect to certain issuances by the Company of its
securities.

     WHEREAS, certain of the Investors (the "EXISTING INVESTORS") hold shares of
the Series A Preferred and possess certain registration rights, information
rights, rights of first offer, and other rights pursuant to the Investor Rights
Agreement dated as of November 19, 2002 among the Company and the Existing
Investors (the "PRIOR RIGHTS AGREEMENT");

     WHEREAS, the Company and the Existing Investors desire to amend the Prior
Rights Agreement and further desire that this Agreement supersede and replace
the Prior Rights Agreement in its entirety; and

     WHEREAS, pursuant to Section 6.5 of the Prior Rights Agreement, the written
consent of the Company and the Existing Investors holding a majority of the
Registrable Securities (as such term is defined in the Prior Rights Agreement)
(the "REQUISITE HOLDERS") is required to amend the Prior Rights Agreement.

     NOW, THEREFORE, in consideration of the mutual promises, representations,
warranties, covenants and conditions set forth in this Agreement, the parties
hereto agree as follows:

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I.   GENERAL.

     1.1 Definitions. As used in this Agreement the following terms shall have
the following respective meanings:

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

          "FORM S-3" means such form under the Securities Act as in effect on
the date hereof or any successor registration form under the Securities Act
subsequently adopted by the SEC that permits inclusion or incorporation of
substantial information by reference to other documents filed by the Company
with the SEC.

          "HOLDER" means any person owning of record Registrable Securities that
have not been sold to the public, or any assignee of record of such Registrable
Securities in accordance with SECTION 2.1 and SECTION 2.10 hereof.

          "INITIAL OFFERING" means the Company's first public offering of its
Common Stock registered under the Securities Act that is the subject of a firm
underwriting commitment.

          "INITIATING HOLDERS" shall mean any Holder or Holders who in the
aggregate hold not less than fifty percent (50%) of the Registrable Securities
then outstanding.

          "QUALIFIED INITIAL OFFERING" means an Initial Offering in which the
price to the public of the Company's Common Stock is not less than $2.10 per
share (as appropriately adjusted for any stock split, stock dividend, stock
combination, recapitalization or similar event) and which results in aggregate
cash proceeds to the Company of at least $35,000,000 (net of underwriting
discounts and commissions).

          "REGISTER," "REGISTERED," AND "REGISTRATION" refer to a registration
effected by preparing and filing a registration statement in compliance with the
Securities Act, and the declaration or ordering of effectiveness of such
registration statement or document.

          "REGISTRABLE SECURITIES" means (a) Common Stock of the Company issued
or issuable upon conversion of the Shares, (b) Common Stock of the Company
issued to Frazier Healthcare Fund ("FRAZIER"), ARCH Venture Fund ("ARCH") and
Scott Minick ("MINICK") pursuant to those certain Common Stock Purchase
Agreements dated November 19, 2002 by and between the Company and each of
Frazier, Arch and Minick and (c) any Common Stock of the Company issued as (or
issuable upon the conversion or exercise of any warrant, right or other security
which is issued as) a dividend or other distribution with respect to, or in
exchange for or in replacement of, the securities described in (a) and (b)
above. Notwithstanding the foregoing, Registrable Securities shall not include
any securities sold by a person to the public pursuant to a registration
statement or Rule 144 or sold in a private transaction in which the transferor's
rights under SECTION 2 of this Agreement are not assigned.


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          "REGISTRABLE SECURITIES THEN OUTSTANDING" shall be the number of
shares determined by calculating the total number of shares of the Company's
Common Stock that are Registrable Securities and either (a) are then issued and
outstanding or (b) are issuable pursuant to then exercisable or convertible
securities.

          "REGISTRATION EXPENSES" shall mean all expenses incurred by the
Company in effecting any registration under SECTIONS 2.2, 2.3 and 2.4 hereof,
including, without limitation, all registration, qualification, and filing fees,
printing expenses, fees and disbursements of counsel for the Company, reasonable
fees and disbursements of a single special counsel for the Holders, blue sky
fees and expenses and the expense of any special audits incident to or required
by any such registration (but excluding the compensation of regular employees of
the Company, which shall be paid in any event by the Company, as well as stock
transfer taxes, underwriting discounts and commissions or, except as expressly
provided herein, fees of special counsel of individual selling Holders).

          "RULE 144" shall mean Rule 144 as promulgated by the SEC under the
Securities Act, as such Rule may be amended from time to time, or any similar
successor rule that may be promulgated by the SEC.

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

          "SECURITIES ACT" shall mean the Securities Act of 1933, as amended.

          "SELLING EXPENSES" shall mean all underwriting discounts and selling
commissions applicable to the sale.

          "SHARES" shall mean the Company's Preferred Stock held by the
Investors and their permitted assigns.

II.  REGISTRATION; RESTRICTIONS ON TRANSFER

     2.1 Restrictions on Transfer.

          (a) Each Holder agrees not to make any disposition of all or any
portion of the Shares or Registrable Securities unless and until:

               (i) There is then in effect a registration statement under the
Securities Act covering such proposed disposition and such disposition is made
in accordance with such registration statement; or

               (ii) (A) The transferee has agreed in writing to be bound by the
terms of this Agreement, (B) such Holder shall have notified the Company of the
proposed disposition and shall have furnished the Company with a detailed
statement of the circumstances surrounding the proposed disposition, and (C) if
reasonably requested by the Company, such Holder shall have


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furnished the Company with an opinion of counsel, reasonably satisfactory to the
Company, that such disposition will not require registration of such shares
under the Securities Act. It is agreed that the Company will not require
opinions of counsel for transactions made pursuant to Rule 144 promulgated under
the Securities Act.

               (iii) Notwithstanding the provisions of paragraphs (i) and (ii)
above, no such registration statement or opinion of counsel shall be necessary
for a transfer by a Holder that is (A) a partnership to another partnership or
corporation that is under common control with such partnership, or to its
partners or former partners in accordance with partnership interests, or to the
estate of any such partners, (B) a corporation to its stockholders in accordance
with their interest in the corporation, or to a parent or subsidiary of the
corporation, or another corporation that has the same parent as the corporation,
(C) a limited liability company to its members or former members in accordance
with their interest in the limited liability company, (D) a trust to a
beneficiary or beneficiaries in accordance with their interest in the trust, (E)
to the Holder's family members or trust for the benefit of an individual Holder
or family members of the Holder, (F) to a partnership, limited liability company
or other entity that is controlled by and was formed primarily for the benefit
of an individual Holder or family members of the Holder, or (G) a transfer not
involving a change in beneficial ownership; provided that in each case the
transferee will be subject to the terms of this Agreement to the same extent as
if such transferee were an original Holder hereunder.

          (b) Each certificate representing Shares or Registrable Securities
shall (unless otherwise permitted by the provisions of the Agreement) be stamped
or otherwise imprinted with a legend substantially similar to the following (in
addition to any legend required under applicable state securities laws) unless,
in the opinion of counsel for the Company, such legend is not required:

          THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE
          SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), AND MAY NOT BE
          OFFERED, SOLD OR OTHERWISE TRANSFERRED, ASSIGNED, PLEDGED OR
          HYPOTHECATED IN THE ABSENCE OF SUCH REGISTRATION OR AN EXEMPTION
          THEREFROM UNDER THE ACT, OR UNLESS THE COMPANY HAS RECEIVED AN OPINION
          OF COUNSEL SATISFACTORY TO THE COMPANY AND ITS COUNSEL THAT SUCH
          REGISTRATION IS NOT REQUIRED, IF SUCH OPINION IS REASONABLY REQUESTED
          BY THE COMPANY.

          THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO CERTAIN RESTRICTIONS
          ON TRANSFER INCLUDING A 180-DAY LOCKUP IN CONNECTION WITH AN INITIAL
          PUBLIC OFFERING AS SET FORTH IN THE INVESTOR RIGHTS AGREEMENT BETWEEN
          THE ISSUER AND THE ORIGINAL HOLDER OF THESE SHARES, A COPY OF WHICH
          MAY BE OBTAINED AT THE PRINCIPAL OFFICE OF THE ISSUER. SUCH TRANSFER
          RESTRICTIONS ARE BINDING ON TRANSFEREES OF THESE SHARES.

          (c) The Company shall be obligated to reissue promptly unlegended
certificates at the request of any holder thereof if, in the opinion of counsel
(which counsel may be counsel to the


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Company and which opinion shall be in writing and delivered to the Company in a
form acceptable to the Company) reasonably acceptable to the Company, the
securities proposed to be disposed of may lawfully be so disposed of without
registration, qualification or legend.

          (d) Any legend endorsed on an instrument pursuant to applicable state
securities laws and the stop-transfer instructions with respect to such
securities shall be removed upon receipt by the Company of an order of the
appropriate blue sky authority authorizing such removal.

     2.2  Demand Registration.

          (a) Subject to the conditions of this SECTION 2.2, if the Company
shall receive a written request from the Initiating Holders that the Company
file a registration statement under the Securities Act covering the registration
of not less than twenty percent (20%) of the Registrable Securities then
outstanding, then the Company shall promptly, but in any case not later than
fifteen (15) days after the receipt thereof, give written notice of such request
to all Holders and, subject to the limitations of this SECTION 2.2, use its best
efforts to effect, as soon as practicable, and in any event within sixty (60)
days of the receipt of such request, the registration under the Securities Act
of all Registrable Securities that the Holders request to be registered.

          (b) If the Initiating Holders intend to distribute the Registrable
Securities covered by their request by means of an underwriting, they shall so
advise the Company as a part of their request made pursuant to this SECTION 2.2
or any request pursuant to SECTION 2.4, and the Company shall include such
information in the written notice it provides to the Holders referred to in
SECTION 2.2(A) or SECTION 2.4(A), as applicable. In such event, the right of any
Holder to include its Registrable Securities in such registration shall be
conditioned upon such Holder's participation in such underwriting and the
inclusion of such Holder's Registrable Securities in the underwriting to the
extent provided herein. A Holder may elect to include in such underwriting all
or fewer than all of the Registrable Securities he holds. All Holders proposing
to distribute their securities through such underwriting shall (together with
the Company) enter into an underwriting agreement in customary form with the
underwriter or underwriters selected for such underwriting by a majority in
interest of the Initiating Holders (which underwriter or underwriters shall be
reasonably acceptable to the Company) and customary selling stockholder
documents, including a custody agreement and power of attorney. Notwithstanding
any other provision of this SECTION 2.2 or SECTION 2.4, if the underwriter
advises the Company in writing that marketing factors require a limitation of
the number of securities to be underwritten (including Registrable Securities)
then the Company shall so advise all Holders of Registrable Securities which
would otherwise be underwritten pursuant hereto, and the number of Registrable
Securities that may be included in the underwriting shall be allocated among all
Holders that have elected to include their securities in the registration in
proportion (as nearly as practicable) to the total number of Registrable
Securities held by each such Holder; provided however, that the number of shares
of Registrable Securities to be included in such underwriting and registration
shall not be reduced unless all other securities of the Company are first
entirely excluded from the underwriting and registration. Any Registrable
Securities excluded or withdrawn from such underwriting shall be withdrawn from
the registration.


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          If a person who has requested inclusion in such registration as
provided above does not agree to the terms of any such underwriting, such person
may withdraw therefrom by written notice to the Company, the underwriter or the
Initiating Holders. Any Registrable Securities or other securities excluded or
withdrawn from such underwriting shall also be withdrawn from such registration.
If shares are so withdrawn from the registration and if the number of shares to
be included in such registration was previously reduced as a result of marketing
factors pursuant to this SECTION 2.2(B), then the Company shall offer to all
Holders who have not so withdrawn their securities from the registration the
right to include additional securities in the registration in an aggregate
amount equal to the number of shares so withdrawn, with such shares to be
allocated among the Holders of Registrable Securities requesting additional
inclusion in proportion (as nearly as practicable) to the amount of Registrable
Securities owned by each such Holder. For any Holder that is a partnership or
corporation, the partners, retired partners and stockholders of such Holder, or
the estates and family members of any such partners and retired partners and any
trusts for the benefit of any of the foregoing persons shall be deemed a single
"Holder," and any pro rata reduction with respect to such "Holder" shall be
based upon the aggregate amount of shares carrying registration rights owned by
all entities and individuals included in such "Holder" as defined in this
sentence.

          (c) The Company shall not be required to effect a registration
pursuant to this SECTION 2.2:

               (i) if the anticipated aggregate offering price, net of
underwriting discounts and commissions, would not exceed $5,000,000;

               (ii) prior to the earlier of (A) three (3) years from the date of
this Agreement and (B) 180 days following the effective date of the registration
statement pertaining to the Initial Offering;

               (iii) after the Company has effected two (2) registrations
pursuant to this SECTION 2.2, and such registrations have been declared or
ordered effective;

               (iv) if, within thirty (30) days of receipt of a written request
from the Initiating Holders pursuant to SECTION 2.2(A), the Company gives notice
to the Holders of the Company's intention to make a public offering within
ninety (90) days; provided that the Company makes reasonable good faith efforts
to cause the registration statement in connection with any such public offering
to become effective;

               (v) if the Company shall furnish to Holders requesting a
registration statement pursuant to this SECTION 2.2 a certificate signed by the
Chief Executive Officer of the Company stating that in the good faith judgment
of the Board of Directors of the Company, it would be seriously detrimental to
the Company and its stockholders for such registration statement to be effected
at such time, and the Board of Directors concludes, as a result, that it is
therefore essential to defer such filing for a period of not more than ninety
(90) days after receipt of the request of the Initiating Holders; provided that
such right to delay a request shall be exercised by the Company not more than
once in any 12-month period; or


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          (vi) if the Initiating Holders propose to dispose of shares of
Registrable Securities that may be immediately registered on Form S-3 pursuant
to a request made pursuant to SECTION 2.4 below.

     2.3  Piggyback Registrations.

          (a) The Company shall notify all Holders of Registrable Securities in
writing at least thirty (30) days prior to the filing of any registration
statement under the Securities Act for purposes of a public offering of
securities of the Company (including, but not limited to, a registration
effected for stockholders other than the Holders, registration statements
relating to its Initial Offering and to secondary offerings of securities of the
Company, but excluding registration statements relating to employee benefit
plans, exchange offers or debt securities or with respect to corporate
reorganizations or other transactions under Rule 145 of the Securities Act).
Each Holder desiring to include in any such registration statement all or any
part of the Registrable Securities held by it shall, within twenty (20) days
after receipt of the above-described notice from the Company, so notify the
Company in writing. In such written notification, a Holder may request that all
or a part of a Holder's Registrable Securities be included in such registration.
The Company shall, subject to the provisions of SECTION 2.3(B) below, include in
such registration (and any related qualification under Blue Sky laws or other
compliance) all the Registrable Securities that each such Holder has requested
to be registered. If a Holder decides not to include all of his Registrable
Securities, or if the number of Registrable Securities to be included is reduced
to fewer than all of his Registrable Securities pursuant to SECTION 2.3(B)
below, in any registration statement thereafter filed by the Company, such
Holder shall nevertheless continue to have the right to include any Registrable
Securities in any subsequent registration statement or registration statements
as may be filed by the Company with respect to offerings of its securities, all
upon the terms and conditions set forth herein.

          (b) If the registration statement under which the Company gives notice
under this SECTION 2.3 is for an underwritten offering, the Company shall so
advise the Holders of Registrable Securities in the written notice provided
pursuant to SECTION 2.3(A) above. In such event, the right of any such Holder to
be included in a registration pursuant to this SECTION 2.3 shall be conditioned
upon such Holder's participation in such underwriting and the inclusion of such
Holder's Registrable Securities in the underwriting to the extent provided
herein. All Holders proposing to distribute their Registrable Securities through
such underwriting shall enter into an underwriting agreement (together with the
Company and the other Holders of securities of the Company with registration
rights to participate therein distributing their securities through such
underwriting) in customary form with the underwriter or underwriters selected
for such underwriting by the Company and reasonably acceptable to the Holders as
agreed upon by the Company and the underwriters, and customary selling
stockholder documents, including a custody agreement and power of attorney.
Notwithstanding any other provision of the Agreement, if the underwriters
determine in good faith that marketing factors require a limitation of the
number of shares to be underwritten to ensure the success of the offering, the
number of shares that may be included in the underwriting shall be allocated,
first, to the Company; second, to the Holders on a pro rata basis based on the
total number of Registrable Securities held by each such Holder; and, third, to
any other selling stockholders of


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the Company on a pro rata basis based on the total number of Registrable
Securities held by each such selling stockholder. Notwithstanding the foregoing,
no such reduction shall reduce the amount of securities of the Holders included
in the registration below thirty percent (30%) of the total amount of securities
included in such registration, unless such offering is the Qualified Initial
Offering and such registration does not include shares of any other selling
stockholders, in which event any or all of the Registrable Securities of the
Holders may be excluded in accordance with the immediately preceding sentence.
If any Holder disapproves of the terms of any such underwriting, such Holder may
elect to withdraw therefrom by written notice to the Company and the
underwriter, delivered at least ten (10) business days prior to the effective
date of the registration statement. Any Registrable Securities excluded or
withdrawn from such underwriting shall be excluded and withdrawn from the
registration. If shares are so withdrawn from the registration and if the number
of shares of Registrable Securities to be included in such registration was
previously reduced as a result of marketing factors, the Company shall then
offer to all persons who have not so withdrawn their securities from the
registration and otherwise have the right to include securities in the
registration the right to include additional securities in the registration in
an aggregate amount equal to the number of shares so withdrawn, with such shares
to be allocated first to the Holders requesting additional inclusion on a pro
rata basis and then to any other selling stockholders of the Company requesting
additional inclusion on a pro rata basis. For any Holder that is a partnership
or corporation, the partners, retired partners and stockholders of such Holder,
or the estates and family members of any such partners and retired partners and
any trusts for the benefit of any of the foregoing persons shall be deemed a
single "Holder," and any pro rata reduction with respect to such "Holder" shall
be based upon the aggregate amount of shares carrying registration rights owned
by all entities and individuals included in such "Holder" as defined in this
sentence.

          (c) The Company shall have the right to terminate or withdraw any
registration initiated by it under this SECTION 2.3 prior to the effectiveness
of such registration whether or not any Holder has elected to include securities
in such registration. The Registration Expenses of such withdrawn registration
shall be borne by the Company in accordance with SECTION 2.5 hereof.

     2.4 Form S-3 Registration. After the Company's Initial Offering, the
Company shall use its best efforts to qualify for registration on Form S-3 or
any comparable or successor form or forms. In case the Company shall receive
from any Holder or Holders of Registrable Securities a written request or
requests that the Company effect a registration on Form S-3 or any similar
short-form registration statement and any related qualification or compliance
with respect to all or a part of the Registrable Securities owned by such Holder
or Holders, the Company will:

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

          (b) as soon as practicable, effect such registration and all such
qualifications and compliances as may be so requested and as would permit or
facilitate the sale and distribution of all or such portion of such Holder's or
Holders' Registrable Securities as are specified in such request, together with
all or such portion of the Registrable Securities of any other Holder or
Holders, joining in such request as are specified in a written request given
within twenty (20) days after receipt of


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<PAGE>

such written notice from the Company; provided, however, that the Company shall
not be obligated to effect any such registration, qualification or compliance
pursuant to this SECTION 2.4:

               (i) if Form S-3 (or any successor or similar form) is not
available for such offering by the Holders;

               (ii) if the Holders, together with the holders of any other
securities of the Company entitled to inclusion in such registration, propose to
sell Registrable Securities and such other securities (if any) at an aggregate
price to the public of less than one million dollars ($1,000,000);

               (iii) if the Company shall furnish to the Holders a certificate
signed by the Chief Executive Officer or President of the Company stating that
in the good faith judgment of the Board of Directors of the Company, it would be
seriously detrimental to the Company and its stockholders for such Form S-3
registration to be effected at such time, and the Board of Directors concludes,
as a result, that it is, therefore, essential to defer the filing of the Form
S-3 registration statement for a period of not more than ninety (90) days after
receipt of the request of the Holder or Holders under this SECTION 2.4;
provided, that such right to delay a request shall be exercised by the Company
not more than once in any 12-month period; or

               (iv) after the Company has effected four (4) registrations on
Form S-3 for the Holders pursuant to this SECTION 2.4, and such registrations
have been declared or ordered effective.

          (c) Subject to the foregoing, the Company shall file a Form S-3
registration statement covering the Registrable Securities and other securities
so requested to be registered as soon as practicable after receipt of the
request or requests of the Holders. Registrations effected pursuant to this
SECTION 2.4 shall not be counted as demands for registration or registrations
effected pursuant to SECTION 2.2 or 2.3, respectively.

     2.5 Expenses of Registration. Except as specifically provided herein, all
Registration Expenses incurred in connection with any registration,
qualification or compliance pursuant to SECTION 2.2, SECTION 2.3 or SECTION 2.4
herein shall be borne by the Company. All Selling Expenses incurred in
connection with any registrations hereunder shall be borne by the holders of the
securities so registered pro rata on the basis of the number of shares so
registered. The Company shall not, however, be required to pay for expenses of
any registration proceeding begun pursuant to SECTION 2.2 if the request for
such registration has been subsequently withdrawn by the Initiating Holders
unless (a) the withdrawal is based upon material adverse information concerning
the Company of which the Initiating Holders were not aware at the time of such
request or (b) the Holders of a majority of Registrable Securities agree to
forfeit their right to one requested registration pursuant to SECTION 2.2, in
which event such right shall be forfeited by all Holders. If the Holders are
required to pay the Registration Expenses, such expenses shall be borne by the
holders of securities (including Registrable Securities) requesting such
registration in proportion to the number of shares for which registration was
requested. If the Company is required to pay the Registration Expenses of a
withdrawn offering pursuant to clause (a) above, or if the Holders agree


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<PAGE>

to pay the Registration Expenses of a withdrawn offering, other than an offering
withdrawn pursuant to clause (a) above, then the Holders shall not forfeit their
rights pursuant to SECTION 2.2 to a demand registration.

     2.6 Obligations of the Company. Whenever required to effect the
registration of any Registrable Securities, the Company shall, as expeditiously
as reasonably possible:

          (a) Prior to the filing of the registration statement and each
amendment thereof (including any documents incorporated by reference in such
registration statement) and each amendment or supplement to the prospectus, make
available for inspection by the Holders of Registrable Securities covered by
such registration statement and any attorney, accountant, or other agent
retained by such Holders all relevant financial and other records, pertinent
corporate documents, and properties of the Company and its subsidiaries, if any,
and shall cause the officers, directors, and employees of the Company to make
reasonably available for inspection all other relevant information reasonably
requested by such Holders in connection therewith, in each case as is customary
for similar due diligence examinations; provided, however, that any information
that is designated in writing by the Company, in good faith, as confidential at
the time of delivery of such information shall be kept confidential by the
Holders or any such attorney, accountant, or agent, unless such disclosure is
required by law after notice to the Company, or such information becomes
available to the public generally or through a third party without an
accompanying obligation of confidentiality.

          (b) Prepare and file with the SEC a registration statement with
respect to such Registrable Securities and use its best efforts to cause such
registration statement to become effective, and, upon the request of the Holders
holding a majority of the Registrable Securities registered thereunder, keep
such registration statement effective for up to 120 days or, if earlier, until
the Holder or Holders have completed the distribution related thereto.

          (c) Prepare and file with the SEC such amendments and supplements to
such registration statement and the prospectus used in connection with such
registration statement as may be necessary to comply with the provisions of the
Securities Act (including the anti-fraud provisions thereof) with respect to the
disposition of all securities covered by such registration statement for the
period set forth in paragraph (b) above.

          (d) Take such action as may be necessary so that (i) any registration
statement, and any amendment thereto, and any prospectus forming a part thereof,
and any amendment or supplement thereto (and each report or other document
incorporated therein by reference in each case) complies in all material
respects with the Securities Act and the Exchange Act, and the respective rules
and regulations thereunder, (ii) any registration statement, and any amendment
thereto, does not, when it becomes effective, 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 the light of the circumstances
under which they were made, not misleading, and (iii) any prospectus forming
part of any registration statement, and any amendment or supplement to such
prospectus, does not include an untrue statement of a material fact or omit to
state a material fact necessary in


                                      -10-

<PAGE>

order to make the statements, in the light of the circumstances under which they
were made, not misleading.

          (e) Furnish to the Holders such number of copies of a prospectus,
including a preliminary prospectus, in conformity with the requirements of the
Securities Act, and such other documents as they may reasonably request in order
to facilitate the disposition of Registrable Securities owned by them.

          (f) Use its best efforts to register and qualify the securities
covered by such registration statement under such other securities or Blue Sky
laws of such jurisdictions as shall be reasonably requested by the Holders;
provided that the Company shall not be required in connection therewith or as a
condition thereto to qualify to do business or to file a general consent to
service of process in any such states or jurisdictions.

          (g) In the event of any underwritten public offering, enter into and
perform its obligations under an underwriting agreement, in usual and customary
form, with the managing underwriter(s) of such offering. Each Holder
participating in such underwriting shall also enter into and perform its
obligations under such an agreement.

          (h) Notify each Holder holding Registrable Securities covered by such
registration statement at any time when a prospectus relating thereto is
required to be delivered under the Securities Act of the happening of any event
as a result of which the prospectus included in such regis