The CAS Registry Mumber 96223-37-9 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,6,2,2 and 3 respectively; the second part has 2 digits, 3 and 7 respectively. Calculate Digit Verification of CAS Registry Number 96223-37: (7*9)+(6*6)+(5*2)+(4*2)+(3*3)+(2*3)+(1*7)=139 139 % 10 = 9 So 96223-37-9 is a valid CAS Registry Number.