The CAS Registry Mumber 141345-63-3 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,4,1,3,4 and 5 respectively; the second part has 2 digits, 6 and 3 respectively. Calculate Digit Verification of CAS Registry Number 141345-63: (8*1)+(7*4)+(6*1)+(5*3)+(4*4)+(3*5)+(2*6)+(1*3)=103 103 % 10 = 3 So 141345-63-3 is a valid CAS Registry Number.