S-3MEF

As filed with the Securities and Exchange Commission on May 25, 2011

Registration No. 333-             

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

RIGEL PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

DELAWARE	94-3248524
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)

1180 Veterans Boulevard

South San Francisco, CA 94080

(650) 624-1100

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

James M. Gower

Chairman of the Board and Chief Executive Officer

Rigel Pharmaceuticals, Inc.

1180 Veterans Boulevard

South San Francisco, CA 94080

(650) 624-1100

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Suzanne Sawochka Hooper

Cooley LLP

3175 Hanover Street

Palo Alto, CA  94304-1130

Approximate date of commencement of proposed sale to the public: As soon as practicable after the effective date of this Registration Statement.

If the only securities being registered on this form are being offered pursuant to dividend or interest reinvestment plans, please check the following box.  o

If any of the securities being registered on this form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box.  x

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  x 333-171159

If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.   o

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  o

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer o	Accelerated filer x
Non-accelerated filer o (Do not check if a smaller reporting company)	Smaller reporting company o

CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities To Be Registered(1)	Proposed Maximum Aggregate Offering Price(2)		Amount of Registration Fee(3)
Common Stock, par value $0.001 per share	$	25,000,000	$	2,902.50

(1)   There are being registered hereunder such indeterminate number of shares of Common Stock as shall have an aggregate initial offering price not to exceed $25,000,000.

(2)   The proposed maximum aggregate offering price per share will be determined by the Registrant in connection with the issuance by the Registrant of the shares of Common Stock registered hereunder.

(3)   Calculated pursuant to Rule 457(o) under the Securities Act.

This Registration Statement shall become effective upon filing with the Securities and Exchange Commission in accordance with Rule 462(b) of the Securities Act of 1933.

EXPLANATORY NOTE AND INCORPORATION BY REFERENCE

This Registration Statement is being filed pursuant to Rule 462(b) of the Securities Act of 1933, as amended, and General Instruction IV(A) to Form S-3 to register an additional $25,000,000 of the Registrant’s common stock, par value $0.001 per share. In accordance with Rule 462(b), this Registration Statement incorporates by reference the contents of the Registrant’s Registration Statement on Form S-3 (File No. 333-171159), filed with the Securities and Exchange Commission on December 14, 2010 and declared effective by the Securities and Exchange Commission on January 7, 2011, including all exhibits thereto and all information incorporated by reference therein, other than the exhibits included herein.

The required opinions and consents are listed on the Exhibit Index attached to and filed with this registration statement.

2

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of South San Francisco, State of California, on the 25th day of May, 2011.

RIGEL PHARMACEUTICALS, INC.
By:	/s/    JAMES M. GOWER
	Name:	James M. Gower
	Title:	Chairman of the Board and Chief Executive Officer

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities indicated below on the date set forth opposite their name.

Signatures		Title	Date
/s/ JAMES M. GOWER		Chairman of the Board, Chief Executive Officer and Director (Principal Executive Officer)	May 25, 2011
James M. Gower
/s/ RYAN D. MAYNARD		Executive Vice President and Chief Financial Officer (Principal Financial and Accounting Officer)	May 25, 2011
Ryan D. Maynard
*		Executive Vice President, President of Discovery and Research, and Director	May 25, 2011
Donald G. Payan
*		Director	May 25, 2011
Bradford S. Goodwin
*		Director	May 25, 2011
Gary A. Lyons
*		Director	May 25, 2011
Walter H. Moos
*		Director	May 25, 2011
Hollings C. Renton
*		Director	May 25, 2011
Peter S. Ringrose
*		Director	May 25, 2011
Stephen A. Sherwin
*By:	/s/ JAMES M. GOWER
	James M. Gower
	Attorney-in-Fact

3

EXHIBIT INDEX

Exhibit Number	Description of the Document
5.1	Opinion of Cooley LLP
23.1	Consent of Independent Registered Public Accounting Firm
23.2	Consent of Cooley LLP (included in Exhibit 5.1)
24.1	Power of Attorney (1)

(1)Previously filed on the signature page to the Registrant’s Registration Statement on Form S-3 (File No. 333-171159), filed with the Securities and Exchange Commission on December 14, 2010, and incorporated by reference herein.

4

EX-5.1

Exhibit 5.1

May 25, 2011

Rigel Pharmaceuticals, Inc.

1180 Veterans Boulevard

South San Francisco, CA 94080

Ladies and Gentlemen:

We have acted as counsel to Rigel Pharmaceuticals, Inc., a Delaware corporation (the “Company”), in connection with the filing of a Registration Statement on Form S-3 (the “Registration Statement”) pursuant to Rule 462(b) of Regulation C promulgated under the Securities Act of 1933, as amended (the “Securities Act”), relating to an aggregate of $25,000,000 of shares of common stock, par value $0.001 per share (“Common Stock”), of the Company (the “Shares”). The Shares are being registered for offering and sale from time to time pursuant to Rule 415 of the General Rules and Regulations promulgated under the Securities Act (the “Securities Act Rules”). The Registration Statement incorporates by reference the Registration Statement on Form S-3 (File No. 333-171159), filed with the Securities and Exchange Commission (the “SEC”) on December 14, 2010 and declared effective by the SEC on January 7, 2011 (the “Related Registration Statement”), including the prospectus which forms a part of the Related Registration Statement (the “Prospectus”), as supplemented from time to time by one or more prospectus supplements (each, a “Prospectus Supplement”).

In connection with this opinion, we have examined and relied upon the originals, or copies certified to our satisfaction, of such records, documents, certificates, opinions, memoranda and other instruments as in our judgment are necessary or appropriate to enable us to render the opinion expressed below. As to certain factual matters, we have relied upon certificates of the officers of the Company and have not sought to independently verify such matters.

In rendering this opinion, we have assumed: (i) the genuineness and authenticity of all signatures on original documents; (ii) the authenticity of all documents submitted to us as originals; (iii) the conformity to originals of all documents submitted to us as copies; (iv) the accuracy, completeness and authenticity of certificates of public officials; and (v) the due authorization, execution and delivery of all documents where authorization, execution and delivery are prerequisites to the effectiveness of such documents. We have also assumed that, at the time of issuance and sale, a sufficient number of shares of Common Stock is authorized and reserved or available for issuance and that the consideration for the issuance and sale of such shares of Common Stock is not less than the par value of the Common Stock, and that, prior to any offering and sale of the Shares, the Company’s board of directors (the “Board”), including any appropriate committee appointed thereby, will duly authorize the price at which the Shares are to be issued and sold.

Our opinion herein is expressed solely with respect to the federal laws of the United States and the Delaware General Corporation Law. We express no opinion as to whether the laws of any jurisdiction are applicable to the subject matter hereof. We are not rendering any opinion as to compliance with any federal or state antifraud law, rule or regulation relating to securities, or to the sale or issuance thereof.

FIVE PALO ALTO SQUARE, 3000 EL CAMINO REAL, PALO ALTO, CA 94306-2155  T: (650) 843-5000  F: (650) 849-7400  WWW.COOLEY.COM

On the basis of the foregoing and in reliance thereon, and subject to the qualifications herein stated, we are of the opinion that, with respect to any offering of the Shares, provided that: (i) the Registration Statement has become effective; (ii) an appropriate Prospectus Supplement with respect to the Shares has been prepared, delivered and filed in compliance with the Securities Act and the applicable Securities Act Rules; (iii) if the Shares are to be sold pursuant to a purchase, underwriting or similar agreement, such agreement has been duly authorized, executed and delivered by the Company and the other parties thereto and has become a valid and binding agreement of the Company; (iv) the Board, including any appropriate committee appointed thereby, and appropriate officers of the Company have taken all necessary corporate action to approve the issuance of the Shares and related matters; and (v) the issuance and sale of the Shares do not violate any applicable law or the operative certificate of incorporation or bylaws of the Company or result in a default under or breach of any agreement or instrument binding upon the Company and comply with any requirement or restriction imposed by any court or governmental body having jurisdiction over the Company, then the Shares, when issued and sold in accordance with any duly authorized, executed and delivered purchase, underwriting or similar agreement, will be duly authorized, validly issued, fully paid and nonassessable.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the reference to our firm under the caption “Legal Matters” in the Prospectus and any Prospectus Supplement included in the Registration Statement and the Related Registration Statement.

Very truly yours,

Cooley LLP

By:	/s/ CHADWICK L. MILLS
	Chadwick L. Mills

2

EX-23.1

EXHIBIT 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in this Registration Statement (Form S-3) of Rigel Pharmaceuticals, Inc. for the registration of common stock of our reports dated March 1, 2011, with respect to the financial statements of Rigel Pharmaceuticals, Inc. and the effectiveness of internal control over financial reporting of Rigel Pharmaceuticals, Inc. included in its Annual Report (Form 10-K) for the year ended December 31, 2010, filed with the Securities and Exchange Commission, and to the reference to our firm under the caption “Experts” in the Registration Statement (Form S-3 No. 333-171159) and related Prospectus of Rigel Pharmaceuticals, Inc. incorporated by reference into this Registration Statement.

/s/ Ernst & Young LLP

Palo Alto, California

May 25, 2011