The CAS Registry Mumber 103063-16-7 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,0,3,0,6 and 3 respectively; the second part has 2 digits, 1 and 6 respectively. Calculate Digit Verification of CAS Registry Number 103063-16: (8*1)+(7*0)+(6*3)+(5*0)+(4*6)+(3*3)+(2*1)+(1*6)=67 67 % 10 = 7 So 103063-16-7 is a valid CAS Registry Number.