Exhibit
4.23


 


 


RIGEL PHARMACEUTICALS, INC.


 


SECOND
INVESTOR RIGHTS AGREEMENT


 


June 26, 2003


 

















 


TABLE OF
CONTENTS


 


 


	
  SECTION 1.

  	
  GENERAL.

  	
   

  
	
   

  	
   

  
	
  1.1

  	
  Definitions.

  	
   

  
	
   

  	
   

  
	
  SECTION
  2.

  	
  REGISTRATION;
  ADDITIONAL REGISTRATION RIGHTS; ETC.

  	
   

  
	
   

  	
   

  
	
  2.1

  	
  Registration of the Securities.

  	
   

  
	
   

  	
   

  	
   

  
	
  2.2

  	
  Suspension
  Periods

  	
   

  
	
   

  	
   

  	
   

  
	
  2.3

  	
  Piggyback Registrations.

  	
   

  
	
   

  	
   

  	
   

  
	
  2.4

  	
  Demand
  Registration.

  	
   

  
	
   

  	
   

  	
   

  
	
  2.5

  	
  Certain
  Obligations of the Company for Piggyback and Demand Registrations.

  	
   

  
	
   

  	
   

  	
   

  
	
  2.6

  	
  Restrictions on Transfer.

  	
   

  
	
   

  	
   

  	
   

  
	
  2.7

  	
  Termination of
  Registration Rights.

  	
   

  
	
   

  	
   

  	
   

  
	
  2.8

  	
  Delay
  of Registration; Furnishing Information.

  	
   

  
	
   

  	
   

  	
   

  
	
  2.9

  	
  Indemnification.

  	
   

  
	
   

  	
   

  	
   

  
	
  2.10

  	
  Assignment of
  Registration Rights.

  	
   

  
	
   

  	
   

  	
   

  
	
  2.11

  	
  Amendment of
  Registration Rights.

  	
   

  
	
   

  	
   

  
	
  SECTION 3.

  	
  CERTAIN COVENANTS OF
  THE PARTIES.

  	
   

  
	
   

  	
   

  
	
  3.1

  	
  Reservation of Common
  Stock.

  	
   

  
	
   

  	
   

  	
   

  
	
  3.2

  	
  Rule 144
  Reporting.

  	
   

  
	
   

  	
   

  	
   

  
	
  3.3

  	
  Observation
  Rights.

  	
   

  
	
   

  	
   

  	
   

  
	
  3.4

  	
  Board of Directors Matters.

  	
   

  
	
   

  	
   

  	
   

  
	
  3.5

  	
  Limitation
  on Subsequent Registration Rights.

  	
   

  
	
   

  	
   

  	
   

  
	
  3.6

  	
  Participation
  Rights.

  	
   

  
	
   

  	
   

  	
   

  
	
  3.7

  	
  Nasdaq Listing.

  	
   

  
	
   

  	
   

  
	
  SECTION 4.

  	
  MISCELLANEOUS.

  	
   

  
	
   

  	
   

  
	
  4.1

  	
  Governing Law.

  	
   

  
	
   

  	
   

  	
   

  
	
  4.2

  	
  No Inconsistent Agreements.

  	
   

  
	
   

  	
   

  	
   

  
	
  4.3

  	
  Successors
  and Assigns.

  	
   

  
	
   

  	
   

  	
   

  
	
  4.4

  	
  Entire
  Agreement.

  	
   

  
	
   

  	
   

  	
   

  
	
  4.5

  	
  Specific
  Enforcement.

  	
   

  
	
   

  	
   

  	
   

  
	
  4.6

  	
  Severability.

  	
   

  
				



 


i

















 


	
  4.7

  	
  Amendment
  and Waiver.

  	
   

  
	
   

  	
   

  	
   

  
	
  4.8

  	
  Notices.

  	
   

  
	
   

  	
   

  	
   

  
	
  4.9

  	
  Attorneys’ Fees.

  	
   

  
	
   

  	
   

  	
   

  
	
  4.10

  	
  Headings.

  	
   

  
	
   

  	
   

  	
   

  
	
  4.11

  	
  Counterparts.

  	
   

  
	
   

  	
   

  	
   

  
	
  4.12

  	
  Aggregation
  of Stock.

  	
   

  
	
   

  	
   

  	
   

  
	
  4.13

  	
  Pronouns.

  	
   

  



 


ii

















 


RIGEL
PHARMACEUTICALS, INC.


SECOND
INVESTOR RIGHTS AGREEMENT


 


This Second Investor Rights Agreement (the
“Agreement”)
is entered into as of June 26, 2003 by and among Rigel Pharmaceuticals,
Inc., a Delaware
corporation (the “Company”),
and the investors listed on Exhibit A
hereto, referred to hereinafter as the “Investors” and each individually as an
“Investor.”


 


Recitals


 


Whereas, the Investors are purchasing
shares of the Company’s common stock, par value $.001 per share (the “Common Stock”), and
warrants to purchase shares of Common Stock pursuant to that certain Common
Stock and Warrant Purchase Agreement (the “Purchase Agreement”) dated as of April 29,
2003 (the “Financing”);


 


Whereas, the obligations in the Purchase
Agreement are conditioned upon the execution and delivery of this Agreement;
and


 


Whereas, in connection with the
consummation of the Financing, the parties desire to enter into this Agreement
in order to grant registration and other rights to the Investors as set forth
below.


 


Now, Therefore, in consideration of the
foregoing recitals and the mutual promises, representations, warranties and
covenants hereinafter set forth and for other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, the parties
hereto agree as follows:


 


SECTION 1.          General.


 


1.1          Definitions.  Capitalized
terms used but not otherwise defined herein shall have the meanings given them
in the Purchase Agreement.  As
used in this Agreement the following terms shall have the following respective
meanings:


 


(a)           “Common Warrants”  means those certain warrants to purchase
Common Stock issued pursuant to the Purchase Agreement and held by the
Investors listed on Exhibit A hereto and their permitted assigns.


 


(b)           “Exchange Act”  means
the Securities Exchange Act of 1934, as amended.


 


(c)           “Form S-3” means
such form under the Securities Act as in effect on the date hereof or any
successor or similar 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.


 


(d)           “Holder”  means
any person owning of record or having the right to acquire Registrable
Securities, or any assignee of record thereof in accordance with
Section 2.10 hereof, which have not been sold to the public.


 


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(e)           “Initiating Holders”  means
the Holders of at least thirty percent
(30%) of the Registrable Securities then outstanding.


 


(f)            “Prior Investor Rights
Agreement”  means that certain Amended and
Restated Investor Rights Agreement, dated as of April 29, 2003, by and among
the Company and the investors named therein.


 


(g)           “Prior Registrable
Securities”  means the “Registrable Securities”
(as defined in the Prior Investor Rights Agreement) then outstanding under the
Prior Investor Rights Agreement, such Prior Rights Holders and their associated
amounts of Prior Registrable Securities are as set forth hereto on Exhibit B.


 


(h)           “Prior Rights Holders”  means
the “Holders” of “Registrable Securities” (each as defined in the Prior
Investor Rights Agreement) then outstanding under the Prior Investor Rights
Agreement.


 


(i)            “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.


 


(j)            “Registrable Securities”  means:
(i) the Shares; (ii) the Warrant Shares; and (iii) any shares of Common
Stock issued as (or issuable upon the conversion or exercise of any warrant,
right or other security that is issued as) a dividend or other distribution
with respect to, or in exchange for or in replacement of, the Shares and
Warrant Shares. Notwithstanding the foregoing, Registrable Securities shall not
include any shares of Common Stock: (A) sold by a person to the public either
pursuant to a registration statement or Rule 144; (B) sold in a private
transaction in which the transferor’s rights under Section 2 of this
Agreement are not assigned; or (C) held by a Holder (together with its
affiliates) during such periods in which all of such shares may be sold by the
Holder pursuant to Rule 144 within 90 days.


 


(k)           “Registration Expenses”  means
all expenses incurred by the Company in complying with Sections 2.1, 2.3
and 2.4 hereof, including, without limitation, all registration and filing fees,
printing expenses, fees and disbursements of counsel for the Company,
reasonable fees and disbursements not to exceed $25,000  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 that shall be paid in any
event by the Company).


 


(l)            “SEC” or “Commission”  means the Securities
and Exchange Commission.


 


(m)          “Securities Act”  means
the Securities Act of 1933, as amended.


 


(n)           “Selling Expenses”  means
all underwriting discounts and selling commissions applicable to a sale of
Registrable Securities.


 


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(o)           “Shares”  means
the shares of Common Stock issued pursuant to the Purchase Agreement and held
by the Investors listed on Exhibit A
hereto and their permitted assigns.


 


(p)            “Special Registration
Statement” means: (i) a registration statement relating to any
employee benefit plan; (ii) a registration statement relating to any corporate
reorganization or transaction under Rule 145 of the Securities Act,
including any registration statements related to the issuance or resale of
securities issued in such a transaction; or (iii) a registration statement in
which the only securities being registered are shares of stock issuable upon
conversion of debt securities.


 


(q)           “Warrant Shares”
means the shares of Common Stock issuable or issued upon exercise of the Common
Warrants.


 


SECTION
2.         Registration; Additional Registration Rights; etc.


 


2.1          Registration of the Securities.  The
Company shall:


 


(a)           prepare
and file with the SEC, as soon as practicable, but in no event later than 10
business days after the Closing Date (as defined in the Purchase Agreement), a
registration statement on Form S-3 (the “Registration Statement”) for an offering to
be made on a delayed or continuous basis pursuant to Rule 415 under the
Securities Act registering the resale from time to time by the Investors of the
Registrable Securities;


 


(b)           use
its commercially reasonable best efforts to cause the Registration Statement to
become effective as soon as practicable and no later than five business days
after the receipt of a notice of “no review” from the SEC or, in the event of SEC
review, no later than 90 days after the Registration Statement is initially
filed by the Company with the SEC;


 


(c)           subject
to Section 2.2, use its commercially reasonable best efforts to prepare and
file with the SEC such amendments and supplements to the Registration Statement
and the related prospectus used in connection therewith (the “Prospectus”) as may
be necessary to keep the Registration Statement current and effective for a
period not exceeding the earlier of: (i) the second anniversary of the initial
effectiveness of the Registration Statement; (ii) the date on which all Holders
may sell all Registrable Securities then held by such Holders without
restriction under Rule 144 of the Securities Act; or (iii) such time as all Registrable
Securities have been sold (together, the “Registration Period”);


 


(d)           furnish
to the Holders with respect to the Registrable Securities registered under the
Registration Statement such number of copies of the Registration Statement and
Prospectuses (including any preliminary prospectuses) in conformity with the
requirements of the Securities Act and such other documents as the Holders may
reasonably request, in order to facilitate the sale or other disposition of all
or any of the Registrable Securities by the Holders;


 


(e)           use
its commercially reasonable best efforts to register and qualify the
Registrable Securities covered by the Registration Statement under such other
securities or Blue Sky laws of such jurisdictions in the United States as shall
be reasonably requested by the Holders; provided, however, that the Company shall
not be required in connection therewith or


 


3

















 


as a condition thereto to
qualify to do business or consent to service of process in any jurisdiction in
which it is not now so qualified or has not so consented;


 


(f)            advise
the Holders promptly after it shall receive notice or obtain knowledge of the
issuance of any stop order by the SEC delaying or suspending the effectiveness
of the Registration Statement or of the initiation of any proceeding for that
purpose; and it will promptly use its commercially reasonable best efforts to
prevent the issuance of any stop order or to obtain its withdrawal at the
earliest possible moment if such stop order should be issued;


 


(g)           notify
each Holder of securities registered 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 Registration Statement, as then in effect, includes an untrue
statement of a material fact or omits to state a material fact required to be
stated therein or necessary to make the statements therein not misleading in
the light of the circumstances then existing; and


 


(h)           bear
all Registration Expenses in connection with the procedures in paragraphs (a)
through (g) of this Section 2.1 and the registration of the Registrable
Securities pursuant to the Registration Statement.


 


2.2          Suspension Periods.


 


(a)           Except
in the event that paragraph (b) below applies, the Company shall: (i) if
necessary to keep the Registration Statement current and effective, promptly
prepare and file from time to time with the SEC post-effective amendments to the
Registration Statement or supplements to the related Prospectus or supplements
or amendments to any document incorporated therein by reference or file any
other required document so that the Registration Statement 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 not
misleading, and so that, as thereafter delivered to 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; (ii) provide the
Holders with copies of any documents filed pursuant to Section 2.2(a)(i); and
(iii) inform the Holders that the Company has complied with its obligations in
Section 2.2(a)(i) (or that, if the Company has filed a post-effective amendment
to the Registration Statement that has not yet been declared effective, the
Company will notify the Holders to that effect, will use its commercially
reasonable best efforts to secure the effectiveness of such post-effective
amendment as promptly as possible and will promptly notify the Holders pursuant
to Section 2.2(a)(i) hereof when the amendment has become effective).


 


(b)           Subject
to Section 2.2(c) below, in the event: (i) of any request by the SEC or any
other federal or state governmental authority during the period of
effectiveness of the Registration Statement for amendments or supplements to
the Registration Statement or related Prospectus or for additional information
so that the Registration Statement 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 not misleading or otherwise fail to
comply with the


 


4

















 


applicable rules and
regulations of the federal securities laws; (ii) of the issuance by the SEC or
any other federal or state governmental authority of any stop order suspending
the effectiveness of the Registration Statement or the initiation of any
proceedings for that purpose; (iii) 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 of any proceeding for such purpose, provided
that, considering the advice of counsel, the Company reasonably believes that
it must qualify in such jurisdiction; (iv) of any event or circumstance that,
considering the advice of counsel, the Company reasonably believes necessitates
the making of any changes in the Registration Statement or related Prospectus,
or any document incorporated or deemed to be incorporated therein by reference,
so that, in the case of the Registration Statement, it will not contain any
untrue statement of a material fact or any omission to state a material fact
required to be stated therein or necessary to make the statements therein not
misleading, and that in the case of a related Prospectus, it will not contain
any untrue statement of a material fact or any omission 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;
or (v) that the Company reasonably believes, considering the advice of counsel,
that the Company may, in the absence of a suspension described hereunder, be
required under state or federal securities laws to disclose any corporate
development, the disclosure of which could reasonably be expected to have a
material adverse effect upon the Company, its stockholders, a potentially
material transaction or event involving the Company, or any negotiations,
discussions or proposals directly relating thereto; then the Company shall
deliver a certificate in writing to each Holder (the “Suspension Notice”)
to the effect of the foregoing and, upon receipt of such Suspension Notice, the
Holder will refrain from selling any Registrable Securities pursuant to the
Registration Statement (a “Suspension”)
until the Holder’s receipt of copies of a supplemented or amended Prospectus
prepared and filed by the Company or until the Holder is advised in writing by
the Company that the current Prospectus may be used and the Holder has received
copies of any additional or supplemental filings that are incorporated or
deemed incorporated by reference in any such Prospectus.  In the event of any Suspension, the Company
will use its commercially reasonable best efforts to cause the use of the
Prospectus so suspended to be resumed as soon as reasonably practicable after
delivery of a Suspension Notice to the Holders. In the event that the Company
shall exercise its right to suspend the effectiveness of the Registration
Statement hereunder, the Registration Period during which the Registration
Statement is to remain effective shall be extended by a period of time equal to
the duration of any Suspensions.


 


(c)           Notwithstanding
the foregoing paragraphs of this Section 2.2, the Holders shall not be
prohibited from selling Registrable Securities under the Registration Statement
as a result of Suspensions on more than two occasions of not more than 45 days
each in any 12-month period; provided,
however, that in no event shall any Suspension pursuant to Section
2.2(b)(iv) exceed ten business days.


 


(d)           Provided
that a Suspension is not then in effect, each Holder may sell Registrable
Securities under the Registration Statement, provided that it arranges for
delivery of a current Prospectus to the transferee of such Registrable
Securities.  Upon receipt of a request
therefor, the Company will provide an adequate number of current Prospectuses
to the Holder and supply copies to any other parties requiring such
Prospectuses.


 


5

















 


2.3          Piggyback Registrations.


 


(a)           The Company shall notify all Holders
of Registrable Securities then outstanding in writing at least ten  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,
registration statements relating to secondary offerings of securities of the
Company, but excluding Special Registration Statements) and shall afford each
such Holder an opportunity to include in such registration statement all or
part of such Registrable Securities held by such Holder.  Each Holder desiring to include in any such
registration statement all or any part of the Registrable Securities held by it
shall, within ten days after the above-described notice from the Company, so
notify the Company in writing.  Such notice
shall state the intended method of disposition of the Registrable Securities by
such Holder.  If a Holder decides not to
include all of its Registrable Securities 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 public offering, the Company shall so
advise the Holders of Registrable Securities then outstanding.  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 in customary form with the
underwriter or underwriters selected for such underwriting by the Company.  Notwithstanding any other provision of this
Agreement, if the underwriter determines in good faith that marketing factors
require a limitation of the number of shares to be underwritten, the number of
shares that may be included in the underwriting shall be allocated: first, to
the Company; second, to the Holders and the Prior Rights Holders on a pro rata
basis based on the aggregate of the Registrable Securities then held by the
Holders under this Agreement and the Prior Registrable Securities then held by
the Prior Rights Holders under the Prior Investor Rights Agreement; and third,
to any stockholders of the Company (other than a Holder or Prior Rights Holder)
on a pro
rata basis; provided, however,
that: (i) no such reduction shall reduce the aggregate amount of securities of
the selling Holders, together with the securities of the Prior Rights Holders,
included in the registration below thirty percent (30%) of the total amount of
securities included in such registration; and (ii) no such reduction shall
reduce the amount of Registrable Securities of the selling Holders included in
the registration unless all Prior Rights Holders exercising piggyback
registration rights in such registration are subject to such reduction in their
Prior Registrable Securities.  Except as
provided above, in no event will shares of any other selling stockholder of the
Company be included in such registration that would reduce the number of shares
that may be included by the Holders and the Prior Rights Holders without the
written consent of the holders of not less than a majority of the aggregate of
the Registrable Securities and the Prior Registrable Securities proposed to be
sold in the offering.  If any
participating Holder disapproves of the terms of any such underwriting, such
participating Holder may elect to withdraw therefrom by written notice to the
Company and the underwriter, delivered 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


 


6

















 


registration.  For any Holder that is a partnership,
corporation, venture capital fund or limited liability company, the partners,
retired partners, members, retired members and stockholders of such Holder, or
the estates and family members of any such partners, retired partners, members,
retired members and any trusts for the benefit of any of the foregoing person
shall be deemed to be 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.


 


2.4          Demand Registration.


 


(a)           In
the event that: (i) the Registration Statement is not declared effective by the
SEC as set forth in Section 2.1(b); (ii) the Holders still hold Registrable
Securities at the end of the Registration Period; or (iii) subject to Section
2.2, the Registration Statement does not remain effective during the
Registration Period, and the Initiating Holders intend to distribute
Registrable Securities, then the Initiating Holders may deliver a written
request to the Company that the Company file a registration statement under the
Securities Act covering the registration of at least $3 million of the
Registrable Securities then outstanding in an underwritten offering. The
Company shall, within 20 business days of the receipt of such request, give
written notice of such request to all Holders, and subject to the limitations
of this Section 2.4, effect, as expeditiously as reasonably possible, the
registration under the Securities Act of all Registrable Securities that all
Holders request to be registered on the form of registration statement then
available to the Company.


 


(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 2.4, and the Company
shall include such information in the written notice referred to in Section
2.4(a). In such event, the right of any Holder to include its Registrable
Securities in such registration under this Section 2.4 shall be conditioned
upon such Holder’s participation in such underwriting and the inclusion of such
Holder’s Registrable Securities in the underwriting (unless otherwise mutually
agreed by a majority in interest of the Initiating Holders and such Holder) to
the extent provided herein.  All Holders
proposing to distribute their securities through such underwriting shall 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). 
Notwithstanding any other provision of this Section 2.4, if the
underwriter advises the Company that marketing factors require a limitation on
the number of securities underwritten (including Registrable Securities), then
the Company shall so advise all Holders of Registrable Securities that would
otherwise be underwritten pursuant hereto, and the number of shares that may be
included in the underwriting shall be allocated to the Holders of such
Registrable Securities pro rata based on the number of
Registrable Securities held by all such Holders (including the Initiating
Holders). In no event shall any
Registrable Securities be excluded from such underwriting unless all other
securities


 


7

















 


are first excluded. Any
Registrable Securities excluded or withdrawn from such underwriting shall be
withdrawn from the registration.


 


(c)           The
Company shall not be required to effect a registration pursuant to this
Section 2.4:


 


(i)            after
the Company has effected three registrations
pursuant to this Section 2.4, and such registrations have been declared or
ordered effective;


 


(ii)           during
the period starting with the date of filing of, and ending on the date one
hundred eighty (180) days following the effective date of, a registration
statement pertaining to a public
offering as described in Section 2.3, other than pursuant to a Special
Registration Statement; provided that the Company makes reasonable
good faith efforts to cause such registration statement to become effective;


 


(iii)         if
within 30 days of receipt of a written request from the Initiating Holders
pursuant to Section 2.4(a), the Company gives notice to the Holders of the
Company’s intention to file a registration statement for a public offering as described in Section
2.3, other than pursuant to a Special Registration Statement,  within
90 days; provided
that if the Company does not file such registration statement within such
90-day period, the Company shall then effect the registration requested by the
Initiating Holders pursuant to Section 2.4;


 


(iv)          if the Company shall
file a registration statement pursuant to this Section 2.3 and then furnish to
the Initiating Holders requesting such registration statement pursuant to this
Section 2.4 a certificate signed by the Chairman of the Board 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 become effective at such time,
in which event the Company shall have the right to defer seeking acceleration
of effectiveness of such filing for a period of not more than 30 days after
receipt of a notice of “no review” or completion of the review process from the
SEC; provided
that such right to delay effectiveness of a requested registration shall be
exercised by the Company not more than once
in any 12-month period; and provided
further that the Company shall not register any securities for the
account of itself or any other stockholder during such period (other than
pursuant to a Special Registration Statement); and


 


(v)            in
any particular jurisdiction in which the Company would be required to qualify
to do business or to execute a general consent to service of process in
effecting such registration, qualification or compliance.


 


2.5          Certain Obligations of the Company for
Piggyback and Demand Registrations.


 


(a)           Whenever
required to effect the registration of any Registrable Securities pursuant to
Section 2.3 or Section 2.4, the Company shall, as expeditiously as reasonably
possible:


 


8

















 


(i)            prepare
and file with the SEC a registration statement with respect to such Registrable
Securities, and use its commercially reasonable best efforts to cause such
registration statement to become effective as soon as practicable;


 


(ii)           subject
to Section 2.5(b), use its commercially reasonable best efforts to prepare and
file with the SEC such amendments and supplements to a registration statement
and prospectus used in connection therewith as may be necessary to keep such
registration statement effective for a period not exceeding, with respect to
each Holder’s Registrable Securities included in such registration, the earlier
of: (i) the second anniversary of the initial effectiveness of such
registration statement; (ii) the date on which the Holder may sell all Registrable
Securities then held by the Holder without restriction under Rule 144 of the
Securities Act; or (iii) such time as all Registrable Securities held by such
Holder have been sold;


 


(iii)         furnish
to the Holders with respect to the Registrable Securities registered under a
registration statement such number of copies of such registration statement,
and related prospectuses, including preliminary prospectuses, in conformity
with the requirements of the Securities Act, and such other documents as such
Holders may reasonably request in order to facilitate the public sale or other
disposition of the Registrable Securities by the Holders;


 


(iv)          use
its commercially reasonable best efforts to register and qualify the securities
covered by such registration statement under such other securities or Blue Sky laws
of such jurisdictions in the United States as shall be reasonably requested by
the Holders; provided, however, that the Company shall not be required in
connection therewith or as a condition thereto to qualify to do business or
consent to service of process in any jurisdiction in which it is not now so
qualified or has not so consented;


 


(v)            advise
the Holders promptly after it shall receive notice or obtain knowledge of the
issuance of any stop order by the SEC delaying or suspending the effectiveness
of a registration statement or of the initiation of any proceeding for that
purpose; and it will promptly use its commercially reasonable best efforts to
prevent the issuance of any stop order or to obtain its withdrawal at the
earliest possible moment if such stop order should be issued;


 


(vi)          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;


 


(vii)         notify
each Holder of securities registered 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 registration statement, as then in effect, includes
an untrue statement of a material fact or omits to state a material fact
required to be stated therein or necessary to make the statements therein not
misleading in the light of the circumstances then existing;


 


9

















 


(viii)        cause
all such Registrable Securities registered under such registration statement to
be listed on each securities exchange on which similar securities issued by the
Company are then listed;


 


(ix)          provide
a transfer agent and registrar for all Registrable Securities registered under
the registration statement and a CUSIP number for all such Registrable
Securities, in each case not later than the effective date of such
registration; and


 


(x)           use
its commercially reasonable efforts to furnish, at the request of any Holder
requesting registration of Registrable Securities under the registration
statement, on the date that such Registrable Securities are delivered to the
underwriters for sale in connection with a registration under the registration
statement, if such securities are being sold through underwriters, or, if such
securities are not being sold through underwriters, on the date that the
registration statement with respect to such securities becomes effective, (A)
an opinion, dated such date, of the counsel for the Company, in form and
substance as is customarily requested by the underwriters in an underwritten
public offering, addressed to the underwriters, if any, and to the Holders
requesting registration of Registrable Securities and (B) a letter dated such
date, from the independent certified public accountants of the Company and any
company acquired by the Company, in form and substance as is customarily given
by independent certified public accountants to underwriters in an underwritten
public offering, addressed to the underwriters, if any, and to the Holders requesting
registration of Registrable Securities.


 


(b)           Subject
to Section 2.5(c) below, in the event: (i) of any request by the SEC or any
other federal or state governmental authority during the period of
effectiveness of a registration statement filed pursuant to Section 2.3 or
Section 2.4 for amendments or supplements to such registration statement or
related prospectus or for additional information so that the Registration
Statement 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 not misleading or otherwise fail to comply with the
applicable rules and regulations of the federal securities laws; (ii) of the
issuance by the SEC or any other federal or state governmental authority of any
stop order suspending the effectiveness of such registration statement or the
initiation of any proceedings for that purpose; (iii) 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 of any proceeding for such purpose,
provided that, considering the advice of counsel, the Company reasonably
believes that it must qualify in such jurisdiction; (iv) of any event or
circumstance that, considering the advice of counsel, the Company reasonably
believes necessitates the making of any changes in such registration statement
or related prospectus, or any document incorporated or deemed to be
incorporated therein by reference, so that, in the case of such registration
statement, it will not contain any untrue statement of a material fact or any
omission to state a material fact required to be stated therein or necessary to
make the statements therein not misleading, and that in the case of a related
prospectus, it will not contain any untrue statement of a material fact or any
omission 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; or (v) that the Company reasonably believes,
considering the advice of counsel, that the Company may, in the absence of a
suspension described hereunder, be required under state or federal securities
laws to disclose any corporate development, the disclosure of


 


10

















 


which could reasonably be
expected to have a material adverse effect upon the Company, its stockholders,
a potentially material transaction or event involving the Company, or any
negotiations, discussions or proposals directly relating thereto; then the
Company shall deliver a Suspension Notice to each Holder to the effect of the
foregoing and, upon receipt of such Suspension Notice, the Holder will refrain
from selling any Registrable Securities pursuant to such registration statement
until the Holder’s receipt of copies of a supplemented or amended prospectus
prepared and filed by the Company or until the Holder is advised in writing by
the Company that the current prospectus may be used and the Holder has received
copies of any additional or supplemental filings that are incorporated or
deemed incorporated by reference in any such prospectus.  In the event of any Suspension, the Company
will use its commercially reasonable best efforts to cause the use of the
prospectus so suspended to be resumed as soon as reasonably practicable after
delivery of a Suspension Notice to the Holders. In the event that the Company
shall exercise its right to suspend the effectiveness of such registration
statement hereunder, the period during which such registration statement is to
remain effective pursuant to Section 2.5(a)(ii) shall be extended by a period
of time equal to the duration of any Suspensions.


 


(c)           Notwithstanding
the foregoing paragraphs of this Section 2.5, the Holders shall not be
prohibited from selling Registrable Securities under a registration statement
filed pursuant to Section 2.4 as a result of Suspensions on more than two
occasions of not more than 45 days each in any 12-month period (it being
understood that (i) any delay in effectiveness of a registration statement
pursuant to Section 2.4(c)(iv) shall be counted as an occasion of Suspension
for purposes of this Section 2.5(c) and (ii) any days of delayed effectiveness
of a registration statement pursuant to Section 2.4(c)(iv) shall be counted as
part of the 45-day total allowed for Suspension under this Section 2.5(c)); provided, however, that in no event shall
any Suspension pursuant to Section 2.5(b)(iv) of a registration statement filed
under Section 2.4 exceed ten business days.


 


(d)           Except
as specifically provided herein, all Registration Expenses incurred in
connection with any registration under Section 2.3 or Section 2.4
shall be borne by the Company.  All
Selling Expenses incurred in connection with any registrations under Section
2.3 or Section 2.4 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 the Registration Expenses of any registration proceeding begun pursuant
to Section 2.4, the request of which has been subsequently withdrawn by
the Initiating Holders unless: (i) 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 (ii) the Holders of a majority
of the Registrable Securities then outstanding agree to forfeit their right to
one requested registration pursuant to Section 2.4 (in which event such
right shall be deemed 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.


 


2.6          Restrictions on Transfer.


 


(a)           Each
Investor agrees that it will not sell, offer to sell, solicit offers to buy,
dispose of, loan, pledge or grant any right with respect to (collectively, a “Disposition”) all or
any portion of the Registrable Securities unless and until:


 


11

















 


(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)
if rights under this Agreement are assigned to the transferee, 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 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.


 


(b)           Notwithstanding
the provisions of Section 2.6(a) above, no such restriction shall apply to a
transfer by a Holder that is: (i) a partnership transferring to its
partners or former partners in accordance with partnership interests;
(ii) a corporation transferring to a wholly-owned subsidiary or a parent
corporation that owns all of the capital stock of the Holder;  (iii) a limited liability company
transferring to its members or former members in accordance with their interest
in the limited liability company; (iv) an affiliated venture fund
transferring to another affiliated venture fund; or (v) an individual
transferring to the Holder’s family member or trust for the benefit of an
individual Holder; provided that in each case the transferee
will agree in writing to be subject to the terms of this Agreement to the same
extent as if the transferee were an original Holder hereunder.


 


(c)           Each
certificate representing the Shares or Warrant Shares shall be stamped or
otherwise imprinted with legends substantially similar to the following (in
addition to any legend required under applicable state securities laws):


 


“THE SHARES REPRESENTED
BY THIS CERTIFICATE HAVE BEEN ACQUIRED FOR INVESTMENT AND HAVE NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “ACT”).  SUCH SHARES MAY NOT BE SOLD OR TRANSFERRED
IN THE ABSENCE OF REGISTRATION OR AN EXEMPTION THEREFROM. RIGEL
PHARMACEUTICALS, INC. MAY REQUIRE AN OPINION OF COUNSEL REASONABLY ACCEPTABLE
TO IT THAT A PROPOSED TRANSFER OR SALE IS IN COMPLIANCE WITH THE ACT.”


 


“THE SALE,
TRANSFER OR VOTING OF THE SHARES REPRESENTED BY THIS CERTIFICATE IS RESTRICTED
BY THE TERMS OF A SECOND INVESTOR RIGHTS AGREEMENT BY AND AMONG RIGEL
PHARMACEUTICALS, INC. AND THE INVESTORS NAMED THEREIN. COPIES OF THE AGREEMENT
MAY BE OBTAINED AT NO COST BY WRITTEN REQUEST MADE BY THE HOLDERS OF RECORD OF
THIS CERTIFICATE TO THE SECRETARY OF RIGEL PHARMACEUTICALS, INC. AT


 


12

















 


THE PRINCIPAL
EXECUTIVE OFFICES OF RIGEL PHARMACEUTICALS, INC.”


 


(d)           The
Company shall be obligated to reissue promptly unlegended certificates at the
request of any Holder thereof if the Holder shall have (i) sold Registrable
Securities pursuant to an effective registration statement or (ii) obtained an
opinion of counsel (which counsel may be counsel to the Company) reasonably
acceptable to the Company to the effect that the securities proposed to be
disposed of may lawfully be so disposed of without registration, qualification
and legend.


 


(e)           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.


 


2.7          Termination of Registration Rights.  All registration rights granted under
this Section 2 shall terminate and be of no further force and effect upon the
earlier of: (i) the date on which the Holders may sell all Registrable
Securities then held by the Holders without restriction under Rule 144 of the
Securities Act; or (ii) such time as all Registrable Securities purchased by
the Investors in the Financing have been sold.


 


2.8          Delay of Registration; Furnishing
Information.


 


(a)           No
Holder shall have any right to obtain or seek an injunction restraining or
otherwise delaying any such registration as the result of any controversy that
might arise with respect to the interpretation or implementation of this
Section 2.


 


(b)           It
shall be a condition precedent to the obligations of the Company to register a
Holder’s Registrable Securities pursuant to Section 2.1, Section 2.3 or
Section 2.4 that such Holder shall furnish to the Company such information
regarding themselves, the Registrable Securities held by them and the intended
method of disposition of such securities as shall be reasonably required to
effect the registration of such Holder’s Registrable Securities.  Upon receipt of such information, the
Company shall promptly update any registration statement (whether or not such
registration statement has been declared effective) used or to be used to
register Registrable Securities.


 


2.9          Indemnification. 
In the event any Registrable Securities are included in a
registration statement under Section 2.1, Section 2.3 or Section 2.4:


 


(a)           To
the extent permitted by law, the Company shall indemnify and hold harmless each
Holder, the partners, members, officers and directors of each Holder, any
underwriter (as defined in the Securities Act) for such Holder and each person,
if any, who controls such Holder or underwriter within the meaning of the
Securities Act or the Exchange Act, against any losses, claims, damages, or
liabilities (joint or several) to which they may become subject under the
Securities Act, the Exchange Act or other federal or state law, insofar as such
losses, claims, damages or liabilities (or actions in respect thereof) arise
out of, or are based upon, any of the following statements, omissions or
violations (collectively a “Violation”) by the Company: (i) any untrue
statement or alleged untrue statement of a material fact contained


 


13

















 


in such registration
statement or incorporated by reference therein, including any preliminary
prospectus or final prospectus contained therein or any amendments or
supplements thereto; (ii) the omission or alleged omission to state
therein a material fact required to be stated therein, or necessary to make the
statements therein not misleading; or (iii) any violation or alleged
violation by the Company of the Securities Act, the Exchange Act, any state
securities law or any rule or regulation promulgated under the Securities Act,
the Exchange Act or any state securities law in connection with the offering
covered by such registration statement; and the Company shall reimburse each
such Holder, partner, member, officer, director, underwriter or controlling
person for any legal or other expenses reasonably incurred by them in
connection with investigating or defending any such loss, claim, damage,
liability or action as such expenses are incurred; provided however, that the
indemnity agreement contained in this Section 2.9(a) shall not apply to
amounts paid in settlement of any such loss, claim, damage, liability or action
if such settlement is effected without the consent of the Company, which
consent shall not be unreasonably withheld, nor shall the Company be liable in
any such case for any such loss, claim, damage, liability or action to the
extent that it arises out of, or is based upon, a Violation that occurs in
reliance upon and in conformity with written information furnished expressly
for use in connection with such registration by or on behalf of such Holder,
partner, member, officer, director, underwriter or controlling person of such
Holder.


 


(b)           To
the extent permitted by law, each Holder shall, if Registrable Securities held
by such Holder are included in such registration statement, indemnify and hold
harmless the Company, each of its directors, its officers and each person, if
any, who controls the Company within the meaning of the Securities Act, any
underwriter and any other Holder selling securities under such registration
statement or any of such other Holder’s partners, directors or officers or any
person who controls such Holder, against any losses, claims, damages or
liabilities (joint or several) to which the Company or any such director,
officer, controlling person, underwriter or other such Holder, or partner,
director, officer or controlling person of such other Holder may become subject
under the Securities Act, the Exchange Act or other federal or state law,
insofar as such losses, claims, damages or liabilities (or actions in respect
thereto) arise out of, or are based upon, any of the following statements:
(i) any untrue statement or alleged untrue statement of a material fact
contained in such registration statement or incorporated by reference therein,
including any preliminary prospectus or final prospectus contained therein or
any amendments or supplements thereto; (ii) the omission or alleged
omission to state therein a material fact required to be stated therein, or
necessary to make the statements therein not misleading; or (iii) any
violation or alleged violation by the Company of the Securities Act  (collectively, a “Holder Violation”), in each case to the
extent (and only to the extent) that such Holder Violation occurs in reliance
upon and in conformity with written information furnished by such Holder under
an instrument duly executed by such Holder and stated to be specifically for
use in connection with such registration; and each such Holder shall reimburse
any legal or other expenses reasonably incurred by the Company or any such
director, officer, controlling person, underwriter or other Holder, or partner,
officer, director or controlling person of such other Holder in connection with
investigating or defending any such loss, claim, damage, liability or action if
it is judicially determined that there was such a Holder Violation; provided,
however, that the indemnity agreement contained in this
Section 2.9(b) shall not apply to amounts paid in settlement of any such
loss, claim, damage, liability or action if such settlement is effected without
the consent of the Holder, which consent shall not be unreasonably withheld; provided
further, that in no event


 


14

















 


shall any indemnity under
this Section 2.9 exceed the net  proceeds
from the offering received by such Holder.


 


(c)           Promptly
after receipt by an indemnified party under this Section 2.9 of notice of
the commencement of any action (including any governmental action), such
indemnified party will, if a claim in respect thereof is to be made against any
indemnifying party under this Section 2.9, deliver to the indemnifying
party a written notice of the commencement thereof, and the indemnifying party
shall have the right to participate in, and, to the extent the indemnifying
party so desires, jointly with any other indemnifying party similarly noticed,
to assume the defense thereof with counsel mutually satisfactory to the
parties; provided,
however, that an indemnified party shall have the right to retain
its own counsel, with the fees and expenses to be paid by the indemnifying
party, if representation of such indemnified party by the counsel retained by
the indemnifying party would be inappropriate due to actual or potential
differing interests between such indemnified party and any other party
represented by such counsel in such proceeding.  The failure to deliver written notice to the indemnifying party
within a reasonable time of the commencement of any such action, if materially
prejudicial to its ability to defend such action, shall relieve such
indemnifying party of liability to the indemnified party under this
Section 2.9 to the extent of such prejudice, but the omission so to
deliver written notice to the indemnifying party will not relieve it of any
liability that it may have to any indemnified party otherwise than under this
Section 2.9.


 


(d)           If
the indemnification provided for in this Section 2.9 is held by a court of
competent jurisdiction to be unavailable to an indemnified party with respect
to any losses, claims, damages or liabilities referred to herein, the
indemnifying party, in lieu of indemnifying such indemnified party hereunder,
shall to the extent permitted by applicable law contribute to the amount paid
or payable by such indemnified party as a result of such loss, claim, damage or
liability in such proportion as is appropriate to reflect the relative fault of
the indemnifying party on the one hand and of the indemnified party on the
other in connection with the Violation(s) or Holder Violation(s) that resulted
in such loss, claim, damage or liability, as well as any other relevant
equitable considerations.  The relative
fault of the indemnifying party and of the indemnified party shall be
determined by a court of law by reference to, among other things, whether the
untrue or alleged untrue statement of a material fact or the omission to state
a material fact relates to information supplied by the indemnifying party or by
the indemnified party and the parties’ relative intent, knowledge, access to
information and opportunity to correct or prevent such statement or omission; provided,
that in no event shall any contribution by a Holder hereunder, when combined
with amounts paid pursuant to Section 2.9(b), exceed the net proceeds from the offering
received by such Holder.


 


(e)           The
obligations of the Company and the Holders under this Section 2.9 shall
survive completion of any offering of Registrable Securities pursuant to a
registration statement under Section 2 and the termination of this
Agreement.  No indemnifying party, in
the defense of any such claim or litigation, shall, except with the consent of
each indemnified party, consent to the entry of any judgment or enter into any
settlement that does not include as an unconditional term thereof the giving by
the claimant or plaintiff to such indemnified party of a release from all
liability in respect to such claim or litigation.


 


15

















 


2.10        Assignment of Registration Rights.  The rights to cause the Company to
register Registrable Securities pursuant to this Section 2 may be assigned
by a Holder to a transferee or assignee of Registrable Securities that: (a) is
a subsidiary, parent, general partner, limited partner, retired partner, member
or retired member, stockholder or affiliated venture fund of a Holder; (b) is a
Holder’s family member or trust for the benefit of an individual Holder; (c)
acquires at least 100,000  shares of Registrable Securities (as
adjusted for stock splits and combinations); or (d) is an entity affiliated by common control (or other related
entity) with such Holder;  provided, however, that: (i) the
transferor shall, within ten days after such transfer, furnish to the Company
written notice of the name and address of such transferee or assignee and the
securities with respect to which such registration rights are being assigned;
and (ii) such transferee shall agree to be subject to all restrictions set
forth in this Agreement.


 


2.11        Amendment of Registration Rights.  Any provision of this Section 2 may
be amended and the observance thereof may be waived (either generally or in a
particular instance and either retroactively or prospectively), only with the
written consent of the Company and the Holders of at least  a majority of the Registrable Securities then outstanding.  Any amendment or waiver effected in accordance
with this Section 2.11 shall be binding upon each Holder and the
Company.  By acceptance of any benefits
under this Section 2, the Holders of Registrable Securities hereby agree
to be bound by the provisions hereunder.


 


SECTION
3.         Certain
Covenants of the Parties.


 


3.1          Reservation of Common Stock.  The Company will at all times reserve
and keep available, solely for issuance and delivery upon the exercise of the
Common Warrants, the Warrant Shares issuable from time to time upon such
exercise.


 


3.2          Rule 144
Reporting.  With a view to making available
to each Holder the benefits of Rule 144 under the Securities Act (or its
successor rule) and any other rule or regulation of the SEC that may at any
time permit the Holder to sell Registrable Securities to the public without
registration or pursuant to Form S-3, the Company covenants and agrees to:  (a) make and keep public information
available, as those terms are understood and defined in Rule 144, until such
time as all Registrable Securities purchased by the Investors in the Financing
have been sold; (b) file with the SEC in a timely manner all reports and other
documents required of the Company under the Securities Act and the Exchange
Act; and (c) furnish to the Holder upon request, as long as the Holder owns any
Registrable Securities, (i) a written statement by the Company that it has
complied with the reporting requirements of Rule 144 of the Securities Act and
the Exchange Act or that it qualifies as a registrant whose securities may be
registered on Form S-3, (ii) a copy of the Company’s most recent Annual Report
on Form 10-K or Quarterly Report on Form 10-Q and (iii) such other information
as may be reasonably requested in order to avail the Holder of any rule or
regulation of the SEC that permits the selling of any such Registrable
Securities without registration or pursuant to such form.


 


3.3          Observation Rights.  For so long as MPM BioVentures
III, L.P. or its affiliates (“MPM Capital”) shall own Registrable Securities
representing not less than 10% of the total shares of Common Stock then
outstanding, the Company shall allow Ms. Ashley Ledbetter (or such other
representative that may be designated by MPM Capital in accordance with this
Section 3.3) to serve as a representative designated by MPM Capital (the “Representative”) to


 


16

















 


attend
all regularly scheduled meetings of the Company’s Board of Directors in a
nonvoting capacity, and in connection therewith, the Company shall give such
Representative copies of all notices, minutes, consents and other materials,
financial or otherwise, which the Company provides to its Board of Directors; provided, however, that: (a) MPM Capital
shall not change or substitute its Representative without providing the Company
with 20 days’ prior notice of such change or substitution;  (b) the Representative shall agree to hold
in confidence and trust and to act in a fiduciary manner with respect to all
information so provided; and (c) the Company reserves the right to exclude such
Representative from access to any material or meeting or portion thereof if the
Company believes that such exclusion is reasonably necessary: (i) to preserve
the attorney-client privilege; (ii) to protect highly confidential information;
or (iii) to prevent the disclosure of trade secrets to a competitor.


 


3.4          Board of Directors Matters.  For so long as MPM Capital shall own Registrable Securities representing not less than
10% of the total shares of Common Stock then outstanding:


 


(a)           the
Company’s Board of Directors shall consist of nine members, and the Company’s
Board of Directors shall be divided into three classes, with each class having
a three-year term;


 


(b)           the
Company shall: (i) use its commercially reasonable best efforts to cause Mr. Dennis
Henner, as designated by MPM Capital (the “Class II Designee”), to be nominated and
elected to Class II of the Company’s Board of Directors at each meeting or
pursuant to each consent of the Company’s stockholders for the election of
Class II directors; (ii) use its commercially reasonable best efforts to cause
Mr. Nick Simon, as designated by MPM Capital (the “Class III Designee”
and collectively with the Class II Designee, the “MPM Designees”), to be nominated and
elected to Class III of the Company’s Board of Directors at each meeting or
pursuant to each consent of the Company’s stockholders for the election of
Class III directors; and (iii) if any MPM Designee elected to the Company’s
Board of Directors ceases to be a member of the Company’s Board of Directors
during such person’s term as a director due to such person’s resignation, death
or removal, the Company shall use its commercially reasonable best efforts,
subject to applicable laws and regulations, to cause such vacancy to be filled
by a replacement designated by MPM Capital, and such designee shall be an MPM
Designee for purposes of this Agreement;


 


(c)           as long as an MPM Designee remains on the
Company’s Board of Directors pursuant to Section 3.4(b), then: (i) the Company shall use its
commercially reasonable best efforts to appoint one of the MPM Designees to the
Nominating Committee of the Company’s Board of Directors; and (ii) the Company
shall not materially amend or modify the Charter of the Nominating Committee of
the Company’s Board of Directors as in effect as of the date of this Agreement;
provided, however, that the
Company shall not be required to make any appointment to a committee of the
Company’s Board of Directors if such appointment could reasonably be expected
to conflict with federal securities laws or any other rules or regulations then
in effect of Nasdaq or any exchange on which the Company’s securities are
listed for trading; and provided further that
the Company shall be able to amend or modify the Charter of the Nominating
Committee of the Company’s Board of Directors as is necessary to not conflict
with any applicable federal securities laws, state laws or any other rules or
regulations then in effect of Nasdaq or any exchange on which the Company’s
securities are listed for trading;


 


17

















 


(d)           as long as an MPM Designee remains on
the Company’s Board of Directors pursuant to Section 3.4(b), then the Company shall use its
commercially reasonable best efforts to appoint one of the MPM Designees to the
Compensation Committee of the Company’s Board of Directors; provided, however, that the Company shall
not be required to make any appointment to a committee of the Company’s Board
of Directors if such appointment could reasonably be expected to conflict with
federal securities laws or any other rules or regulations then in effect of
Nasdaq or any exchange on which the Company’s securities are listed for
trading; and


 


(e)           the
Company shall use its commercially reasonable efforts to maintain the Company’s
amended and restated certificate of incorporation and bylaws, as amended, to
permit the Company to indemnify its directors and officers to the fullest
extent permitted by law (including to seek to amend such certificate and bylaws
to the extent the law permits greater indemnification than then permitted by
such certificate and bylaws).


 


3.5          Limitation on Subsequent Registration
Rights.  For so long as any
Registrable Securities remain outstanding, after the date of this Agreement, the
Company shall not, without the prior written consent of the holders of at least
a majority  of the aggregate of (a) the
Registrable Securities then outstanding under this Agreement and (b) the Prior
Registrable Securities then outstanding under the Prior Investor Rights
Agreement, enter into any agreement, other than in connection with a Special
Registration Statement, with any holder or prospective holder of any securities
of the Company that would grant such holder registration rights on a parity with, or senior to, those
granted to the Holders hereunder.


 


3.6          Participation
Rights.


 


(a)           The
parties hereby agree that each Investor, so long as such Investor and its
respective affiliates beneficially own at least 10% of all of the outstanding
shares of Common Stock, shall have the right (the “Participation Right”),
but not the obligation, to purchase its Pro Rata Share (as defined below) of
all (or any part) of any New Securities (as defined below). “Pro Rata Share”
equals a fraction, (i) the numerator of which shall be the number of shares of
Common Stock then owned by such Investor (or receivable by such Investor upon
conversion or exercise of all then outstanding convertible or exercisable
securities held by such Investor) and (ii) the denominator of which shall be
the total number of shares of Common Stock then outstanding.


 


(b)           For
purposes of this Agreement, “New Securities” shall mean any shares of, or securities
convertible into or exchangeable or exercisable for any shares of, the
Company’s capital stock; provided, however,
that the term “New Securities” does not include:


 


(i)            any
securities, including shares of Common Stock, to be issued pursuant to a
“public offering” (as such term is determined by the rules, regulations and
guidelines of the National Association of Securities Dealers) of such
securities, or issued pursuant to a registration statement on a Form S-4 or S-8
or substantially equivalent successor form, or, upon the approval of a majority
of the entire Board of Directors of the Company (i.e., a majority of the total
number of directors then in office), any shares issued pursuant to registration
statement and offered publicly (the parties hereto agree that merely because an
offering is to be 


 


18

















 


undertaken as a
“take-down” from a shelf registration statement, that factor will not be the
sole determinative factor as to whether such offering is a “public offering”);


 


(ii)           shares
of Common Stock (or options therefor) issued or issuable to employees,
officers, directors, consultants or other service providers of the Company
pursuant to stock options or other stock incentive agreements or plans approved
by a majority of the Company’s Board of Directors and not for capital-raising
transactions;


 


(iii)         any
securities issued upon the conversion or exercise of an convertible or
exercisable securities outstanding as of the date hereof;


 


(iv)          any
shares of Common Stock (or any other security) issued in connection with any
stock split, stock dividend, combination, recapitalization or similar corporate
action for which no consideration is paid or payable;


 


(v)            any
shares of Common Stock (or any other security) issued in connection with (A)
any corporate collaboration agreement, (B) any licensing agreement, (C) any
payment or settlement of any obligation under a material contract and (D) as
compensation for any services rendered to the Company;


 


(vi)          any
securities issued pursuant to an acquisition of the Company approved by its
Board of Directors by means of (A) merger or other form of corporate
reorganization in which outstanding shares of the Company are exchanged for
securities or other consideration issued, or caused to be issued, by the
acquiring corporation or its subsidiary and pursuant to which the holders of
the outstanding voting securities of the Company immediately prior to such
merger or other form of corporate reorganization fail to hold equity securities
representing a majority of the voting power of the Company or surviving entity
immediately following such merger or other form of corporate reorganization or
(B) a sale of all or substantially all the assets of the Company approved by
the Company’s Board of Directors;


 


(vii)         any
shares of Common Stock or Warrants issued pursuant to the Financing;


 


(viii)        any
securities issued in connection with bona fide equipment financings or bona
fide lease agreements; or


 


(ix)          any
securities issued in transactions approved by the Board of Directors (i.e., a
majority of the total number of directors then in office) as being excluded
from the provisions of this Section 3.6.


 


(c)           If
the Company proposes to undertake any issuance of New Securities, it shall,
prior to any such issuance, give written notice to the Investors of its bona
fide intention to issue New Securities (the “Company Notice”), describing the type of
New Securities proposed to be issued, the total number or quantity of New
Securities proposed to be issued, and the price and the general terms upon
which the Company proposes to issue such New Securities. Each Investor may
elect to purchase or acquire its Pro Rata Share of such New Securities (an “Electing Party”) by
delivering written notice (the “Participation Notice”) of its election to so purchase or
acquire such New Securities at the price and upon the general terms specified
in the


 


19

















 


Company Notice and
stating the quantity of New Securities to be purchased (not to exceed its Pro
Rata Share). The Participation Notice shall be delivered to the Company within
five (5) business days after the date of delivery of the Company Notice, and
the obligations of the Electing Party thereunder to purchase the elected number
or percentage of New Securities, and the obligations of the Company to sell
such New Securities to the Electing Party, shall be contingent upon the
consummation of the sale or other transaction pursuant to which the New
Securities are proposed to be issued. 
The number or amount of New Securities specified in the Participation
Notice shall be subject to automatic and proportionate reduction in the event
that the total number or quantity of New Securities sold by the Company is
reduced below the number or quantity specified in the Company Notice. If any
Investor fails to give the Participation Notice to the Company within such five
business-day period, or specifies in the Participation Notice that such
Investor will only purchase part, but not all, of such Investor’s Pro Rata
Share (a “Nonpurchasing
Investor”), then such Nonpurchasing Investor shall forfeit the
right hereunder to purchase that part of its Pro Rata Share of such New
Securities that it did not so agree to purchase, and the Company shall promptly
give each Investor (if any) who has timely agreed to purchase its full Pro Rata
Share of such offering of New Securities (a “Purchasing Investor”) written notice of
the failure of any Nonpurchasing Investor to purchase such Nonpurchasing
Investor’s full Pro Rata Share of such offering of New Securities (the “Overallotment Notice”).  Such Overallotment Notice shall be given to
each Purchasing Investor within three business days of the expiration of the
five business-day period. Each Purchasing Investor shall have a right of
overallotment such that such Purchasing Investor may agree to purchase a
portion of the Nonpurchasing Investor’s unpurchased Pro Rata Share of such
offering on a pro rata basis according to the relative Pro Rata Shares of the
Purchasing Investor at any time within three business days after receiving the
Overallotment Notice.


 


(d)           If
the Investors fail to exercise in full the Participation Right within such five
plus three plus three business-day period, then the Company shall have 180
calendar days thereafter to sell the New Securities with respect to which the
Investors’ Participation Rights hereunder were not exercised, at a price not
less than, and upon general terms not more favorable than those specified in
the Company Notice. If the Company has not issued and sold the New Securities
within such 180 calendar-day period, then the Company shall not thereafter
issue or sell any New Securities without again first offering such New
Securities to the Investors pursuant to this Section 3.6.


 


(e)           From
and after the date of this Agreement, the Company shall not enter into any
agreement with any holder or prospective holder of any securities that would
allow such holder or prospective holder a participation right, right of first
refusal, right of first offer or other similar right which is on terms
materially more favorable to such holder or prospective holder than, or in
preference to, the Participation Right granted to the Investors hereunder.


 


3.7          Nasdaq Listing.  The
Company shall use its commercially reasonable best efforts to maintain the
listing of the Registrable Securities on Nasdaq.


 


SECTION 4.         Miscellaneous.


 


4.1          Governing Law.  This
Agreement shall be governed by, and construed in accordance with, the internal
laws of the State of California, without giving effect to the


 


20

















 


principles of conflicts
of law. The parties agree that
any action brought by either party under or in relation to this Agreement,
including without limitation to interpret or enforce any provision of this
Agreement, shall be brought in, and each party agrees to and does hereby submit
to the jurisdiction and venue of, any state or federal court located in the
County of San Francisco, California.


 


4.2          No
Inconsistent Agreements.  The Company has not entered, as of the date
hereof, into any agreement with respect to any of its securities that is
inconsistent with, diminishes or otherwise limits, the rights granted to the
Holders of Registrable Securities in this Agreement or otherwise conflicts with
the provisions hereof.


 


4.3          Successors and Assigns.  Except as otherwise expressly provided herein, the provisions
hereof shall inure to the benefit of, and be binding upon, the parties hereto
and their respective successors, assigns, heirs, executors and administrators
and shall inure to the benefit of, and be enforceable by, each person who shall
be a Holder of Registrable Securities from time to time; provided, however, that
prior to the receipt by the Company of adequate written notice of the transfer
of any Registrable Securities specifying the full name and address of the
transferee, the Company may deem and treat the person listed as the holder of
such shares in its records as the absolute owner and holder of such shares for
all purposes, including the payment of dividends or any redemption price.


 


4.4          Entire Agreement. 
This Agreement, including the Exhibits hereto, constitutes the full
and entire understanding and agreement between the parties with regard to the
subject hereof and no party shall be liable or bound to any other in any manner
by any oral or written representations, warranties, covenants and agreements
except as specifically set forth herein. 
Each party expressly represents and warrants that it is not relying on
any oral or written representations, warranties, covenants or agreements
outside of this Agreement; provided, however,
that the parties hereto acknowledge that the Investors have relied on those
certain Consents, Waivers and Agreements, dated as of April 29, 2003, executed
by holders of a majority of the “Registrable Securities” outstanding under (and
as defined in) that certain Amended and Restated Investor Rights Agreement,
dated as of February 3, 2000, by and among the Company and the investors named
therein.


 


4.5          Specific
Enforcement.  It is agreed and understood that monetary
damages would not adequately compensate an injured party for the breach of
Section 3.4 of this Agreement by any other party, that Section 3.4 of this
Agreement shall be specifically enforceable, and that any breach or threatened
breach of Section 3.4 of this Agreement shall be the proper subject of a
temporary or permanent injunction or restraining order.  Further, each party hereto waives any claim
or defense that there is an adequate remedy at law for such breach or threatened
breach Section 3.4 of this Agreement.


 


4.6          Severability.  In
case any provision contained in this Agreement should be invalid, illegal or
unenforceable in any respect, the validity, legality and enforceability of the
remaining provisions contained herein shall not in any way be affected or impaired
thereby.


 


21

















 


4.7          Amendment and Waiver.


 


(a)           Except
as otherwise expressly provided, this Agreement may be amended or modified only
upon the written consent of the Company and the Holders of at least a majority
of the Registrable Securities then outstanding.


 


(b)           Except
as otherwise expressly provided, the obligations of the Company and the rights
of the Holders under this Agreement may be waived only with the written consent
of the Holders of at least a majority
of the Registrable Securities then outstanding.


 


(c)           For
the purposes of determining the number of Holders entitled to vote or exercise
any rights hereunder, the Company shall be entitled to rely solely on the list
of record holders of its stock as maintained by or on behalf of the Company.


 


4.8          Notices. 
All notices, requests, consents and other communications hereunder shall
be in writing; shall be mailed (a) if within the domestic United States, by
first-class registered or certified airmail, by nationally recognized overnight
express courier, postage prepaid, or by facsimile or (b) if delivered from
outside the United States, by International Federal Express or facsimile; shall
be deemed given: (i) if delivered by first-class registered or certified mail
domestic, three business days after so mailed; (ii) if delivered by nationally
recognized overnight carrier, one business day after so mailed; (iii) if
delivered by International Federal Express, two business days after so mailed;
or (iv) if delivered by facsimile, upon electric confirmation of receipt; and
shall be delivered as addressed as follows:


 


(a)           if
to the Company, to:


 


Rigel Pharmaceuticals, Inc.


1180 Veterans Boulevard


South San
Francisco, CA  94080


Attn:  James M.
Gower


Chairman and Chief Executive Officer


Phone:  (650)
624-1100


Telecopy: 
(650) 624-1133


 


with
a copy to:


 


Cooley Godward llp


Five Palo Alto Square


3000 El Camino Real


Palo Alto, CA 
94306


Attn: Suzanne Sawochka Hooper


Phone: (650) 843-5000


Telecopy: (650) 849-7400


 


(b)           if
to the Investors, at the addresses as set forth on Exhibit A hereto, or at such other address or addresses as may
have been furnished to the Company in writing.


 


4.9          Attorneys’ Fees. 
In the event that any suit or action is instituted under or in
relation to this Agreement, including without limitation to enforce any
provision in this Agreement, the prevailing party in such dispute shall be
entitled to recover from the losing party


 


22

















 


all fees, costs and expenses
of enforcing any right of such prevailing party under or with respect to this
Agreement, including without limitation, such reasonable fees and expenses of
attorneys and accountants, which shall include, without limitation, all fees,
costs and expenses of appeals.


 


4.10        Headings.  The
headings of the various sections of this Agreement have been inserted for
convenience of reference only and shall not be deemed to be part of this
Agreement.


 


4.11        Counterparts.  This
Agreement may be executed in two or more counterparts, each of which shall
constitute an original, but all of which, when taken together, shall constitute
but one instrument, and shall become effective when one or more counterparts
have been signed by each party hereto and delivered to the other parties.


 


4.12        Aggregation of Stock.  All shares of
Registrable Securities held or acquired by affiliated entities or persons or
persons or entities under common management or control shall be aggregated
together for the purpose of determining the availability of any rights under
this Agreement.


 


4.13        Pronouns.  All
pronouns contained herein, and any variations thereof, shall be deemed to refer
to the masculine, feminine or neutral, singular or plural, as to the identity
of the parties hereto may require.


 


 


[Remainder of page
intentionally left blank.]


 


23

















 


In Witness Whereof, the parties hereto have
executed this Second
Investor Rights Agreement as of the date set forth
in the first paragraph hereof.


 


	
  COMPANY:

  	
  INVESTORS:

  
	
   

  	
   

  	
   

  
	
  RIGEL
  PHARMACEUTICALS, INC.

  	
  MPM
  BIOVENTURES III, L.P.

  
	
   

  	
   

  
	
   

  	
   

  
	
  By:

  	
  /s/
  James M. Gower

  	
   

  	
  By:

  	
  MPM BioVentures III GP, L.P.,

  
	
   

  	
   

  	
  its General Partner

  
	
   

  	
   

  
	
  Name:  James M. Gower

  	
  By:

  	
  MPM BioVentures III LLC,

  
	
   

  	
   

  	
  its General Partner

  
	
   

  	
   

  
	
  Title:
   Chairman and Chief Executive Officer

  	
  By:

  	
  /s/
  Dennis Henner

  	
   

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  Name:
  Dennis Henner

  
	
   

  	
   

  
	
   

  	
  Title:  Series A Member

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  MPM
  BIOVENTURES III-QP, L.P.

  
	
   

  	
   

  
	
   

  	
  By:

  	
  MPM BioVentures III GP, L.P.,

  
	
   

  	
   

  	
  its General Partner

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By:

  	
  MPM BioVentures III LLC,

  
	
   

  	
   

  	
  its General Partner

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By:

  	
  /s/
  Dennis Henner

  	
   

  
	
   

  	
   

  
	
   

  	
  Name:
  Dennis Henner

  
	
   

  	
   

  
	
   

  	
  Title:  Series A Member

  
							



 


SECOND INVESTOR RIGHTS
AGREEMENT


SIGNATURE PAGE


 

















 


	
   

  	
  MPM BIOVENTURES III GMBH & CO.

  
	
   

  	
  BETEILIGUNGS KG

  
	
   

  	
   

  
	
   

  	
  By:

  	
  MPM BioVentures III GP, L.P., in its

  
	
   

  	
   

  	
  capacity as the Managing Limited

  
	
   

  	
   

  	
  Partner

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  MPM BioVentures III LLC,

  
	
   

  	
   

  	
  its General Partner

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/
  Dennis Henner

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  Name:
  Dennis Henner

  
	
   

  	
   

  	
   

  
	
   

  	
  Title:  Series A Member

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  MPM BIOVENTURES III PARALLEL

  
	
   

  	
  FUND, L.P.

  
	
   

  	
   

  
	
   

  	
  By:

  	
  MPM BioVentures III GP, L.P.,

  
	
   

  	
   

  	
  its General Partner

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  MPM BioVentures III LLC,

  
	
   

  	
   

  	
  its General Partner

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/
  Dennis Henner

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  Name:
  Dennis Henner

  
	
   

  	
   

  	
   

  
	
   

  	
  Title:
  Series A Member

  



 

















 


	
   

  	
  MPM ASSET MANAGEMENT

  
	
   

  	
  INVESTORS 2003 BVIII LLC

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/
  Dennis Henner

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  Name:
  Dennis Henner

  
	
   

  	
   

  
	
   

  	
  Title:  Manager

  
	
   

  	
   

  
	
   

  	
  MPM BIOEQUITIES MASTER FUND,

  
	
   

  	
  L.P.

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By:

  	
  MPM BioEquities GP, L.P.,

  
	
   

  	
   

  	
  its General Partner

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  MPM BioEquities GP LLC,

  
	
   

  	
   

  	
  its General Partner

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/
  Robert W. Liptak

  	
   

  
	
   

  	
   

  
	
   

  	
  Name:
  Robert W. Liptak

  
	
   

  	
   

  
	
   

  	
  Title:  General Partner

  



 

















 


	
   

  	
  ALTA CALIFORNIA PARTNERS, L.P.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  Alta California Management
  Partners, L.P.

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Garrett Gruener

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  V.P. of Finance & Admin.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  ALTA EMBARCADERO PARTNERS, LLC

  
	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Garrett Gruener

  	
   

  
	
   

  	
   

  	
  V.P. of Finance & Admin.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  ALTA
  BIOPHARMA PARTNERS II, L.P.

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  Alta
  BioPharma Management Partners

  
	
   

  	
   

  	
  II,
  LLC

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Hilary Strain

  	
   

  
	
   

  	
   

  	
  V.P. of Finance & Admin.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  ALTA EMBARCADERO BIOPHARMA

  
	
   

  	
  PARTNERS II, LLC

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ Hilary Strain

  	
   

  
	
   

  	
   

  	
  V.P. of Finance & Admin.

  
					



 

















 


	
   

  	
  FRAZIER HEALTHCARE IV, L.P.

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  FHM
  IV, LP, its General Partner

  
	
   

  	
  By:

  	
  FHM
  IV, LLC, its General Partner

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/
  Nathan Every

  	
   

  
	
   

  	
   

  	
  Nathan
  Every, Member

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  FRAZIER AFFILIATES IV, L.P.

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  FHM
  IV, LP, its General Partner

  
	
   

  	
  By:

  	
  FHM
  IV, LLC, its General Partner

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/
  Nathan Every

  	
   

  
	
   

  	
   

  	
  Nathan
  Every, Member

  



 

















 


	
   

  	
  HBM BIOVENTURES (CAYMAN) LTD.

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/
  John Arnold

  	
   

  
	
   

  	
   

  
	
   

  	
  Name:    John
  Arnold

  
	
   

  	
   

  
	
   

  	
  Title:      Chairman
  and Managing Director

  



 

















 


Exhibit A


 


INVESTORS


 


	
  Investor

  	
   

  	
  Aggregate

  Purchase Price

  	
   

  	
  Shares
  Purchased

  	
   

  	
  Warrant

  Shares

  	
   

  	
  Total

  Registrable

  Securities

  	
   

  
	
  MPM
  BioVentures III, L.P.

  111 Huntington Avenue

  31st Floor

  Boston, MA 02199

  (617) 425-9200 (T)

  (617) 425-9201 (F)

  	
   

  	
  $

  	
  1,399,248.00

  	
   

  	
  242,925

  	
   

  	
  48,585

  	
   

  	
  291,510

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  MPM
  BioVentures III-QP, L.P.

  111 Huntington Avenue

  31st Floor

  Boston, MA 02199

  (617) 425-9200 (T)

  (617) 425-9201 (F)

  	
   

  	
  $

  	
  20,810,574.72

  	
   

  	
  3,612,947

  	
   

  	
  722,589

  	
   

  	
  4,335,536

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  MPM
  BioVentures III GmbH & Co. Parallel-Beteiligungs KG

  111 Huntington Avenue

  31st Floor

  Boston, MA 02199

  (617) 425-9200 (T)

  (617) 425-9201 (F)

  	
   

  	
  $

  	
  1,758,752.64

  	
   

  	
  305,339

  	
   

  	
  61,068

  	
   

  	
  366,407

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  MPM
  BioVentures III Parallel Fund, L.P.

  111 Huntington Avenue

  31st Floor

  Boston, MA 02199

  (617) 425-9200 (T)

  (617) 425-9201 (F)

  	
   

  	
  $

  	
  628,502.40

  	
   

  	
  109,115

  	
   

  	
  21,823

  	
   

  	
  130,938

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  MPM
  Asset Management Investors 2003 BVIII LLC

  111 Huntington Avenue

  31st Floor

  Boston, MA 02199

  (617) 425-9200 (T)

  (617) 425-9201 (F)

  	
   

  	
  $

  	
  402,923.52

  	
   

  	
  69,952

  	
   

  	
  13,990

  	
   

  	
  83,942

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  MPM
  BioEquities Master Fund, L.P.

  111 Huntington Avenue

  31st Floor

  Boston, MA 02199

  (617) 425-9200 (T)

  (617) 425-9201 (F)

  	
   

  	
  $

  	
  999,999.36

  	
   

  	
  173,611

  	
   

  	
  34,722

  	
   

  	
  208,333

  	
   

  



 

















 


	
  Alta
  California Partners, L.P.

  One Embarcadero Center

  Suite 4050

  San Francisco, CA 94111

  (415) 362-4022 (T)

  (415) 362-6178 (F)

  	
   

  	
  $

  	
  977,662.08

  	
   

  	
  169,733

  	
   

  	
  33,947

  	
   

  	
  203,680

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Alta
  Embarcadero Partners, LLC

  One Embarcadero Center

  Suite 4050

  San Francisco, CA 94111

  (415) 362-4022 (T)

  (415) 362-6178 (F)

  	
   

  	
  $

  	
  22,337.28

  	
   

  	
  3,878

  	
   

  	
  776

  	
   

  	
  4,654

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Alta
  BioPharma Partners II, L.P.

  One Embarcadero Center

  Suite 4050

  San Francisco,

  CA 94111

  (415) 362-4022 (T)

  (415) 362-6178 (F)

  	
   

  	
  $

  	
  6,269,368.32

  	
   

  	
  1,088,432

  	
   

  	
  217,686

  	
   

  	
  1,306,118

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Alta
  Embarcadero BioPharma Partners II, LLC

  One Embarcadero Center

  Suite 4050

  San Francisco, CA 94111

  (415) 362-4022 (T)

  (415) 362-6178 (F)

  	
   

  	
  $

  	
  230,630.40

  	
   

  	
  40,040

  	
   

  	
  8,008

  	
   

  	
  48,048

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Frazier
  Healthcare IV, L.P.

  601 Union Street, Suite 3300

  Seattle, WA 98101

  (206) 621-7200 (T)
(206) 621-1848 (F)

  	
   

  	
  $

  	
  7,462,120.32

  	
   

  	
  1,295,507

  	
   

  	
  259,101

  	
   

  	
  1,554,608

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Frazier
  Affiliates IV, L.P.

  601 Union Street, Suite 3300

  Seattle, WA 98101

  (206) 621-7200 (T)
(206) 621-1848 (F)

  	
   

  	
  $

  	
  37,877.76

  	
   

  	
  6,576

  	
   

  	
  1,315

  	
   

  	
  7,891

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  HBM
  BioVentures (Cayman) Ltd.

  Unit 10 Eucalyptus Building

  Crewe Road

  P.O. Box 30852 SMB

  Grand Cayman, Cayman Islands

  (345) 946-8002 (T)

  (345) 946-8003 (F)

  	
   

  	
  $

  	
  4,999,996.80

  	
   

  	
  868,055

  	
   

  	
  173,611

  	
   

  	
  1,041,666

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  TOTALS

  	
   

  	
  $

  	
  45,999,993.60

  	
   

  	
  7,986,110

  	
   

  	
  1,597,221

  	
   

  	
  9,583,331

  	
   

  



 

















 


Exhibit B


 


PRIOR
RIGHTS HOLDERS


 


As of April 29, 2003


 


 


	
  Investor
  Name and Address

  	
   

  	
  Registrable

  Securities

  	
   

  
	
  Alta California
  Partners, L, P.

  One Embarcadero Center, Suite 4050

  San Francisco, CA 94111

  	
   

  	
  4,579,314

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
  Alta Embarcadero
  Partners, LLC

  One Embarcadero Center, Suite 4050

  San Francisco, CA 94111

  	
   

  	
  104,618

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
  CB Capital Investors,
  L.P.

  c/o Chase Capital Partners

  Partners 380

  Madison Avenue, 12th Floor

  New York, NY 10017

  	
   

  	
  833,333

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
  Fortune Maker
  Corporation

  11/F King Fook Building

  30-32 Des Voeux Road Central

  HONG KONG

  	
   

  	
  550,000

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
  Frazier & Company,
  Inc.

  601 Union Street, Suite 2110

  Seattle, WA 98101

  	
   

  	
  15,234

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
  Frazier Healthcare II,
  L.P.

  601 Union Street, Suite 2110

  Seattle, WA 98101

  	
   

  	
  4,332,575

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
  Johnson & Johnson
  Development Corporation

  One Johnson & Johnson Plaza

  New Brunswick, NJ 08933

  	
   

  	
  1,666,666

  	
   

  



 

















 


	
  Lombard Odier Darier
  Hentsch & Cie

  11, rue de la Corraterie

  1204 Geneva

  Switzerland

  	
   

  	
  4,169,538

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
  Novartis Pharma AG

  Head Financial Investments

  CH-4002

  Basil, Switzerland

  	
   

  	
  2,000,000

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
  Pfizer, Inc.

  235 East 42nd Street

  New York, NY 10017

  	
   

  	
  1,000,000

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
  Thomas Volpe

  c/o Rigel Pharmaceuticals, Inc.

  1180 Veterans Boulevard

  South San Francisco, CA 94080

  	
   

  	
  33,333

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
  Total:

  	
   

  	
  19,284,611