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             Attn: 
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             Ms. Laura Crotty 
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             Re: 
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             Castle Biosciences, Inc. (the “Company”) – Request for Acceleration 
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             Registration Statement on Form S-1 (File No. 333-239354) 
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             Very truly yours, 
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             SVB Leerink LLC 
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             Robert W. Baird & Co. Incorporated 
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             As representatives of the several Underwriters 
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             By: SVB Leerink LLC 
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             By: 
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              /s/ Ryan Lindquist 
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             Name: Ryan Lindquist 
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             Title:   Managing Director 
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             By: Robert W. Baird & Co. Incorporated 
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             By: 
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             /s/ Ryan Engelhardt 
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             Name: Ryan Engelhardt 
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             Title: Managing Director 
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