10 DLC stands for 10 digit long code. Also know as a local phone number. vs aa short code. The usage of 10 DLC for Broadcast and P2P texting is regulated and survey closely by the mobile phone providers. The providers have created a joint organization that approves particular phone numbers for usage with text messaging and in particular Political Text messaging. NO Political Text message can be send without authorization. Fundamentally the permit allows the phone carrier to associate the phone number with a particular campaign. The campaign has to provide an EIN as well as evidence that they are a legitimate political campaign.