ID should be such that it either defines your company name (eg Flipkart) or your content (eg VERIFY for OTP). ID cannot be a person name or related to government authorities/firms, banks, stock market etc. For eg (SBIONL, Irctci, LICIND). If you still wish to use one, you or your client need to provide us a letterhead signed by the organisation stating that you are allowed to use their Sender IDs. For stock market messages, your user must be registered with SEBI and should be able to provide SEBI certificate.