If you stay in India and you are using any Indian Mobile Operator service such as Docomo, Idea, Airtel etc then you must have received SMS with from different Companies as LM-ICICIB , TD-610437, LM-OLXInd, BP-ATMSBI, AM-DOMINO etc.
Have you ever Thought from where these Prefixes come and how they set this?
These format are Specified by TRAI and is used by the BULK SMS provider . The last 6 letter or Number are for the Organization to Choose such as OLXInd for OLX India or DOMINO for Domino’s Pizza etc.
Now the First Letter is for the Telecom Service Provider used by the Bulk SMS provider and the Second Letter is for the Location of Origin of the message.
Here is a List in a Table which explains the Telecom Service Provider details and Location details-
So when to you get a SMS as TA-DOCOMO it means Its from Tata Teleservices from Andhra Pradesh. Share this Among your Friends .