Exhibit 4.6


THE
SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT
OF 1933, AS AMENDED (THE “ACT”), OR UNDER THE SECURITIES LAWS OF ANY
STATE.  THESE SECURITIES ARE SUBJECT TO
RESTRICTIONS ON TRANSFERABILITY AND RESALE AND MAY NOT BE TRANSFERRED OR RESOLD
EXCEPT AS PERMITTED UNDER THE ACT AND THE APPLICABLE STATE SECURITIES LAWS,
PURSUANT TO REGISTRATION OR EXEMPTION THEREFROM.  THE ISSUER OF THESE SECURITIES MAY REQUIRE AN
OPINION OF COUNSEL IN FORM AND SUBSTANCE SATISFACTORY TO THE ISSUER TO THE
EFFECT THAT ANY PROPOSED TRANSFER OR RESALE IS IN COMPLIANCE WITH THE ACT AND
ANY APPLICABLE STATE SECURITIES LAWS.


COMMON STOCK PURCHASE WARRANT


	
  Warrant No. CS-23

  	
   

  	
  100,000 Shares

  
	
  July 24, 2006

  	
   

  	
   

  



 


RIGEL PHARMACEUTICALS, INC.


WARRANT
FOR THE PURCHASE OF SHARES OF COMMON STOCK


1.             Issuance. 
For value received, this Warrant is issued to KWACKER LIMITED, a corporation
organized and existing under the laws of England, by RIGEL PHARMACEUTICALS, INC., a Delaware corporation (hereinafter
with its successors called the “Company”),
in partial consideration for that certain Amendment No. Three to
Build-to-Suit Lease, dated as of the date hereof, between the Company and
Slough BTC, LLC, as landlord (“Amendment Three”).


2.             Purchase
Price; Number of Shares.  The registered holder of this
Warrant (the “Holder”),
commencing on the date hereof, is entitled upon surrender of this Warrant with
the subscription form annexed hereto duly executed, at the principal office of
the Company, to purchase from the Company one hundred thousand (100,000) fully
paid and nonassessable shares (the “Shares”)
of common stock, $.001 par value per share, of the Company (the “Common Stock”), at a price per share of
$10.57 (the “Purchase Price”).  Until such time as this Warrant is exercised
in full or expires, the Purchase Price and the securities issuable upon
exercise of this Warrant are subject to adjustment as hereinafter
provided.  The person or persons under
whose name or names any certificate representing shares of Common Stock is
issued hereunder shall be deemed to have become the holder of record of the
shares represented thereby as at the close of business on the date this Warrant
is exercised with respect to such shares, whether or not the transfer books of
the Company shall be closed.


3.             Payment
of Purchase Price.  The Purchase Price may be paid (i) in
cash or by check; (ii) by the surrender by the Holder to the Company of
any promissory notes or other obligations issued by the Company, with all such
notes and obligations so surrendered being credited against the Purchase Price
in an amount equal to the principal amount thereof plus accrued interest to the
date of surrender; or (iii) by any combination of the foregoing.









 



4.             Net
Issue Election.  The Holder may elect to receive, without the
payment by the Holder of any additional consideration, shares of Common Stock
equal to the value of this Warrant or any portion hereof by the surrender of
this Warrant or such portion to the Company, with the net issue election notice
annexed hereto duly executed, at the principal office of the Company.  Thereupon, the Company shall issue to the
Holder such number of fully paid and nonassessable shares of Common Stock as is
computed using the following formula:




	
  X =

  	
  Y (A – B)

  
	
  A

  






 


	
  where:

  	
   

  	
  X =

  	
   

  	
  the number of shares of Common Stock to be issued to
  the Holder pursuant to this Section 4.

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  Y =

  	
   

  	
  the number of shares of Common Stock covered by this
  Warrant in respect of which the net issue election is made pursuant to this
  Section 4.

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  A =

  	
   

  	
  the Fair Market Value (defined below) of one share
  of Common Stock, as determined at the time the net issue election is made
  pursuant to this Section 4.

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  B =

  	
   

  	
  the Purchase Price in effect under this Warrant at
  the time the net issue election is made pursuant to this Section 4.

  



 


“Fair
Market Value” of a share of Common Stock as of a particular
date (the “Determination Date”) shall mean the
average of the closing or last reported sale prices of the Common Stock as
reported on the Nasdaq National Market over the 30-day period ending five
business days prior to the Determination Date;
provided, however, that (i) if the Common Stock is neither
traded on the Nasdaq National Market nor on a national securities exchange,
then Fair Market Value shall be the average of the closing or last reported
sale prices of the Common Stock over the 30-day period ending five business
days prior to the Determination Date reflected in the over-the-counter market,
as reported by the National Quotation Bureau, Inc. or any organization
performing a similar function, or if closing prices are not then routinely
reported for the over-the-counter market, the average of the last bid and asked
prices of the Common Stock over the 30-day period ending five business days
prior to the Determination Date, and (ii) if there is no public market for
the Common Stock, then Fair Market Value shall be determined in good faith by
the Company’s Board of Directors.


5.             Partial
Exercise.  This Warrant may be exercised in part, and
the Holder shall be entitled to receive a new warrant, which shall be dated as
of the date of this Warrant, covering the number of shares in respect of which
this Warrant shall not have been exercised.


6.             Fractional
Shares.  In no event shall any fractional share of
Common Stock be issued upon any exercise of this Warrant.  If, upon exercise of this Warrant as an
entirety, the Holder would, except as provided in this Section 6, be
entitled to receive a fractional share of Common Stock, then the Company shall
pay in lieu thereof, the Fair Market Value of such fractional share in cash.









 



7.             Expiration
Date.  This Warrant or any Successor Warrant (as
defined in Section 10 below) shall remain exercisable until the close of
business on July 24, 2013, when it shall expire and thereafter be void.


8.             Reserved
Shares; Valid Issuance.  The Company covenants that it
will at all times from and after the date hereof reserve and keep available
such number of its authorized shares of Common Stock, free from all preemptive
or similar rights therein, as will be sufficient to permit the exercise of this
Warrant in full into shares of Common Stock upon such exercise.  The Company further covenants that such shares
as may be issued pursuant to such exercise will, upon issuance, be duly and
validly issued, fully paid and nonassessable and free from all taxes, liens and
charges with respect to the issuance thereof.


9.             Stock
Splits and Dividends.  If after the date hereof the Company shall
subdivide the Common Stock, by split-up or otherwise, or combine the Common
Stock, or issue additional shares of Common Stock in payment of a stock
dividend on the Common Stock, the number of shares of Common Stock issuable on
the exercise of this Warrant shall forthwith be proportionately increased in
the case of a subdivision or stock dividend, or proportionately decreased in
the case of a combination, and the Purchase Price shall forthwith be
proportionately decreased in the case of a subdivision or stock dividend, or
proportionately increased in the case of a combination.


10.          Mergers and Reclassifications.


(a)           If
after the date hereof the Company shall enter into any Reorganization (as
hereinafter defined), then, as a condition of such Reorganization, lawful
provisions shall be made, and duly executed documents evidencing the same from
the Company or its successor shall be delivered to the Holder (a “Successor Warrant”), so that the Holder shall thereafter
have the right to purchase, at a total price not to exceed that payable upon
the exercise of this Warrant in full, the kind and amount of shares of stock
and other securities and property receivable upon such Reorganization by a
holder of the number of shares of Common Stock which might have been purchased
by the Holder immediately prior to such Reorganization, and in any such case
appropriate provisions shall be made with respect to the rights and interest of
the Holder to the end that the provisions hereof (including without limitation,
provisions for the adjustment of the Purchase Price and the number of shares
issuable hereunder and the provisions relating to the net issue election) shall
thereafter be applicable in relation to any shares of stock or other securities
and property thereafter deliverable upon exercise hereof.


(b)           For
the purposes of this Section 10:


(i)            the term “Acquisition
Transaction” shall include without limitation any consolidation of
the Company with, or merger of the Company into, another corporation or other
business organization (other than a merger in which the Company is the
surviving corporation and which does not result in any reclassification or
change of the outstanding Common Stock); and


(ii)           the term “Reorganization”
shall include without limitation any reclassification, capital reorganization
or change of the Common Stock (other than as a result of









 



a subdivision, combination or stock dividend provided
for in Section 9 hereof), an Acquisition Transaction, or any sale or
conveyance to another corporation or other business organization of all or
substantially all of the assets of the Company.


11.          Certificate
of Adjustment.  Whenever the Purchase Price is adjusted, as
herein provided, the Company shall promptly deliver to the Holder a certificate
of the Company’s Chief Financial Officer setting forth the Purchase Price after
such adjustment and setting forth a brief statement of the facts requiring such
adjustment.


12.          Notices of Record Date, Etc. 
In the event of:


(a)           any taking by the Company of a record of
the holders of any class of securities for the purpose of determining the
holders thereof who are entitled to receive any dividend or other distribution,
or any right to subscribe for, purchase, sell or otherwise acquire or dispose
of any shares of stock of any class or any other securities or property, or to
receive any other right;


(b)           any reclassification of the capital stock
of the Company, capital reorganization of the Company, consolidation or merger
involving the Company, or sale or conveyance of all or substantially all of its
assets; or


(c)           any voluntary or involuntary dissolution,
liquidation or winding-up of the Company;


then
in each such event the Company will provide or cause to be provided to the
Holder a written notice thereof.  Such
notice shall be provided at least fifteen (15) calendar days prior to the
date specified in such notice on which any such action is to be taken.


13.          Representations,
Warranties and Covenants.  This Warrant is issued and
delivered by the Company and accepted by each Holder on the basis of the
following representations, warranties and covenants made by the Company:


(a)           The Company has all necessary authority
to issue, execute and deliver this Warrant and to perform its obligations
hereunder.  This Warrant has been duly
authorized, issued, executed and delivered by the Company and is the valid and
binding obligation of the Company, enforceable in accordance with its terms,
except as enforceability may be limited by bankruptcy, insolvency,
reorganization or other similar laws of general application affecting the
enforcement of Holder’s rights or by general equity principles or public policy
concerns.


(b)           The shares of Common Stock issuable upon
the exercise of this Warrant have been duly authorized and reserved for issuance
by the Company and, when issued in accordance with the terms hereof, will be
validly issued, fully paid and nonassessable.


(c)           The issuance, execution and delivery of
this Warrant do not, and the issuance of the shares of Common Stock upon the
exercise of this Warrant in accordance with the terms hereof will not,
(i) violate or contravene the Company’s Amended and Restated Certificate
of Incorporation or by-laws, or any law, statute, regulation, rule, judgment or
order applicable to the Company, (ii) violate, contravene or result in a
breach or default under any









 



material contract, agreement or instrument to which
the Company is a party or by which the Company or any of its assets are bound
or (iii) require the consent or approval of or the filing of any notice or
registration with any person or entity.


14.          Amendment
and Waiver.  The terms of this Warrant may be amended,
modified or waived only with the written consent of the party against which
enforcement of the same is sought.


15.          Representations
and Covenants of the Holder.  This Common
Stock Purchase Warrant has been entered into by the Company in reliance upon
the following representations and covenants of the Holder, which by its
acceptance hereof the Holder hereby confirms:


(a)           Investment
Purpose.  The right to acquire Common Stock or the
Common Stock issuable upon exercise of the Holder’s rights contained herein
will be acquired for investment and not with a view to the sale or distribution
of any part thereof, and the Holder has no present intention of selling or
engaging in any public distribution of the same except pursuant to a
registration or exemption.


(b)           Accredited
Investor.  Holder is an “accredited investor” within the
meaning of the Securities and Exchange Commission’s Rule 501 of Regulation D,
as presently in effect.


(c)           Private
Issue.  The Holder understands (i) that the
Common Stock issuable upon exercise of the Holder’s rights contained herein is
not registered under the 1933 Act or qualified under applicable state
securities laws on the ground that the issuance contemplated by this Warrant
will be exempt from the registration and qualifications requirements thereof
and (ii) that the Company’s reliance on such exemption is predicated on
the representations set forth in this Section 15.


(d)           Financial
Risk.  The Holder has such knowledge and experience
in financial and business matters as to be capable of evaluating the merits and
risks of its investment and has the ability to bear the economic risks of its
investment.


16.          Notices, Transfers, Etc.


(a)           Any notice or written communication
required or permitted to be given to the Holder may be given by certified mall
or delivered to the Holder at the address most recently provided by the Holder
to the Company.


(b)           Subject to compliance with applicable
federal and state securities laws, this Warrant may be transferred by the
Holder with respect to any or all of the shares purchasable hereunder.  Upon surrender of this Warrant to the
Company, together with the assignment notice annexed hereto duly executed, for
transfer of this Warrant as an entirety by the Holder, the Company shall issue
a new warrant of the same denomination to the assignee.  Upon surrender of this Warrant to the
Company, together with the assignment hereof properly endorsed, by the Holder
for transfer with respect to a portion of the shares of Common Stock
purchasable hereunder, the Company shall issue a new warrant to the assignee,
in such denomination as shall









 



be requested by the Holder hereof, and shall issue to
such Holder a new warrant covering the number of shares in respect of which
this Warrant shall not have been transferred.


(c)           In case this Warrant shall be mutilated,
lost, stolen or destroyed, the Company shall issue a new warrant of like tenor
and denomination and deliver the same (i) in exchange and substitution for
and upon surrender and cancellation of any mutilated Warrant or (ii) in
lieu of any Warrant lost, stolen or destroyed, upon receipt of an affidavit of
the Holder or other evidence reasonably satisfactory to the Company of the
loss, theft or destruction of such Warrant and an indemnification of loss by
the Holder in favor of the Company.


17.          Transfer
to Comply with the Securities Act of 1933.   This Warrant may not be exercised and neither
this Warrant nor any of the Shares, nor any interest in either, may be offered,
sold, assigned, pledged, hypothecated, encumbered or in any other manner
transferred or disposed of, in whole or in part, except in compliance with
applicable United States federal and state securities laws and the terms and
conditions hereof.  Each Warrant shall
bear a legend in substantially the same form as the legend set forth on the
first page of this Warrant.  Each
certificate for Shares issued upon exercise of this Warrant, unless at the time
of exercise such Shares are acquired pursuant to a registration statement that
has been declared effective under the Securities Act of 1933, as amended (the “Securities
Act”), and applicable blue sky laws, shall bear a legend substantially in the
following form:


THE SECURITIES
REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933,
AS AMENDED (THE “ACT”), OR UNDER THE SECURITIES LAWS OF ANY STATE.  THESE SECURITIES ARE SUBJECT TO RESTRICTIONS
ON TRANSFERABILITY AND RESALE AND MAY NOT BE TRANSFERRED OR RESOLD EXCEPT AS
PERMITTED UNDER THE ACT AND THE APPLICABLE STATE SECURITIES LAWS, PURSUANT TO
REGISTRATION OR EXEMPTION THEREFROM.  THE
ISSUER OF THESE SECURITIES MAY REQUIRE AN OPINION OF COUNSEL IN FORM AND
SUBSTANCE SATISFACTORY TO THE ISSUER TO THE EFFECT THAT ANY PROPOSED TRANSFER
OR RESALE IS IN COMPLIANCE WITH THE ACT AND ANY APPLICABLE STATE SECURITIES
LAWS.


Any certificate for any Shares issued at any time in exchange or
substitution for any certificate for any Shares bearing such legend (except a
new certificate for any Shares issued after the acquisition of such Shares
pursuant to a registration statement that has been declared effective under the
Securities Act) shall also bear such legend unless, in the opinion of counsel
for the Company, the Shares represented thereby need no longer be subject to
the restriction contained herein.  The
provisions of this Section 17 shall be binding upon all subsequent holders
of certificates for Shares bearing the above legend and all subsequent holders
of this Warrant, if any.


18.          Rights of Holder.  Holder shall
not, by virtue hereof, be entitled to any rights of a stockholder of the
Company, either at law or equity, and the rights of Holder are limited to those
expressed in this Warrant.  Nothing
contained in this Warrant shall be construed as conferring upon Holder hereof
the right to vote or to consent or to receive notice as a stockholder of the









 



Company on any matters or with respect to any rights
whatsoever as a stockholder of the Company. 
No dividends or interest shall be payable or accrued in respect of this
Warrant or the interest represented hereby or the Shares purchasable hereunder
until, and only to the extent that, this Warrant shall have been exercised in
accordance with its terms.


19.          “Market Stand Off” Agreement. 
Holder hereby agrees not to sell, transfer, make any short sale of,
grant any option for the purchase of, or enter into any hedging or similar
transaction with the same economic effect as a sale of, any Common Stock (or
other securities) of the Company held by Holder for a period specified by a
representative of the underwriters of Common Stock (or other securities) of the
Company not to exceed ninety (90) days following the effective date of a
registration statement of the Company filed under the Securities Act; provided that all officers and directors
of the Company and each holder of that number of shares of Common Stock equal
to or greater than the number of Shares then issuable upon exercise of this
Warrant enter into similar agreements.


20.          No
Impairment.  The Company will not, by amendment of its
Certificate or through any reclassification, capital reorganization,
consolidation, merger, sale or conveyance of assets, dissolution, liquidation,
issue or sale of securities or any other voluntary action, avoid or seek to
avoid the observance or performance of any of the terms of this Warrant, but
will at all times in good faith assist in the carrying out of all such terms
and in the taking of all such action as may be necessary or appropriate in
order to protect the rights of the Holder.


21.          Governing
Law.  The provisions and terms of this Warrant
shall be governed by and construed in accordance with the internal laws of the
State of California.


22.          Successors
and Assigns.  This Warrant shall be binding upon the
Company’s successors and assigns and shall inure to the benefit of the Holder’s
successors, legal representatives and permitted assigns.


23.          Business Days. 
If the last or appointed day for the taking of any action required or
the expiration of any rights granted herein shall be a Saturday or Sunday or a
legal holiday in California, then such action may be taken or right may be
exercised on the next succeeding day which is not a Saturday or Sunday or such
a legal holiday.









 



IN WITNESS WHEREOF, the Company has duly caused this Warrant to
be signed by its duly authorized officer and to be dated as of the date first
written above.


 


	
  

  	
   

  	
  Company:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  RIGEL
  PHARMACEUTICALS, INC.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/ James M. Gower 

  
	
   

  	
   

  	
   

  	
  James M. Gower

  	
   

  
	
   

  	
   

  	
   

  	
  Chief Executive Officer

  	
   

  



 









 



SUBSCRIPTION


	
  To:

  	
   

  	
  Date:

  



 


The undersigned hereby subscribes for                               
shares of Common Stock covered by this Warrant. 
The certificate(s) for such shares shall be issued in the name of the
undersigned or as otherwise indicated below:


 


	
  

  	
   

  
	
   

  	
  Signature

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  Name for Registration

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  Mailing Address

  



 


NET
ISSUE ELECTION NOTICE


	
  To:

  	
   

  	
  Date:

  



 


The undersigned hereby elects under Section 4 to
surrender the right to purchase                                                 
shares of Common Stock pursuant to this Warrant.  The certificate(s) for such shares issuable
upon such net issue election shall be issued in the name of the undersigned or
as otherwise indicated below:


 


	
  

  	
   

  
	
   

  	
  Signature

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  Name for Registration

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  Mailing Address

  










 



ASSIGNMENT


For value received                                         
hereby sells, assigns and transfers unto                                   


[Please print or type the name and address of
Assignee]


the
within Warrant, and does hereby irrevocably constitute and appoint                            
                                  
its attorney to transfer the within Warrant on the books of the within named
Company with full power of substitution on the premises.


	
  DATED:

  	
   

  	
   

  	
   

  	
   

  
	
   

  
	
   

  
	
  IN THE
  PRESENCE OF: