| ☐  |  | Preliminary Proxy Statement | 
| ☐  |  | Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) | 
| ☐  |  | Definitive Proxy Statement | 
| ☒  |  | Definitive Additional Materials | 
| ☐  |  | Soliciting Material under §240.14a-12 | 
| RIGEL PHARMACEUTICALS, INC. | 
| (Name of Registrant as Specified in Its Charter) | 
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|  (Name of Person(s) Filing Proxy Statement, if other than the Registrant) | 
| ☒  |  | No fee required. | 
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| ☐  |  | Fee paid previously with preliminary materials. | 
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| ☐  |  | Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11. | 

