The CAS Registry Mumber 603962-08-9 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 6,0,3,9,6 and 2 respectively; the second part has 2 digits, 0 and 8 respectively. Calculate Digit Verification of CAS Registry Number 603962-08: (8*6)+(7*0)+(6*3)+(5*9)+(4*6)+(3*2)+(2*0)+(1*8)=149 149 % 10 = 9 So 603962-08-9 is a valid CAS Registry Number.