California Resale License number validator. Validates Letters and Numbers or Number only. Letters: First 2 letters can be SR, SS, ST , SX, SY, SZ (TAT Code) Next optional letter can be S,X,Y,Z. Next letters must be a minimum of two and a maximum of 3 (District Code). Numbers: Can be 8-9 numbers. Numbers can be delimited with a hypen or spaces after the first 2 numbers. Note: I use () to extract the information I want for use in other scripts.