The CAS Registry Mumber 12003-69-9 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 1,2,0,0 and 3 respectively; the second part has 2 digits, 6 and 9 respectively. Calculate Digit Verification of CAS Registry Number 12003-69: (7*1)+(6*2)+(5*0)+(4*0)+(3*3)+(2*6)+(1*9)=49 49 % 10 = 9 So 12003-69-9 is a valid CAS Registry Number.