We are the data access layer between social networks and the analytics community, making it easy for you to get access to social media data. Socialgist (Effyis, Inc.) is a registered data broker that collects social media/forum posts and sells them to clients; there is no self-service opt-out form. You must email privacy@socialgist.com and include every social media handle or username you want the request to cover, otherwise they say they cannot match your request to their records. They verify identity and aim to respond within 45 days, and note all consumer opt-out requests must go through that email address (Global Privacy Control signals have no effect).