The CAS Registry Mumber 107265-06-5 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,0,7,2,6 and 5 respectively; the second part has 2 digits, 0 and 6 respectively. Calculate Digit Verification of CAS Registry Number 107265-06: (8*1)+(7*0)+(6*7)+(5*2)+(4*6)+(3*5)+(2*0)+(1*6)=105 105 % 10 = 5 So 107265-06-5 is a valid CAS Registry Number.