The CAS Registry Mumber 122726-03-8 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,2,2,7,2 and 6 respectively; the second part has 2 digits, 0 and 3 respectively. Calculate Digit Verification of CAS Registry Number 122726-03: (8*1)+(7*2)+(6*2)+(5*7)+(4*2)+(3*6)+(2*0)+(1*3)=98 98 % 10 = 8 So 122726-03-8 is a valid CAS Registry Number.