<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by FlyingRev:
...why can't someone just write "Rule 120" on the ticket themselves?</font>
Cause what's actually supposed to be done is that the ticket agent should enter 'endorsed to XX Airline, Rule 120, ATO/DATE/AGENT SINE,
and then be officially stamp validated, to be official'
Example:
TO AA
Rule 120
LAXATO/17APR/2P (STAMP)