Professional vs non-professional subscriber status

Exchange rules require everyone receiving real-time options data to declare whether they're a professional or non-professional subscriber. A non-professional is broadly an individual using the data for personal, non-commercial purposes, not on behalf of a firm, adviser, broker-dealer, or institution. Exchange fees differ sharply between the two, which is why the declaration matters.

Set it under Account → Subscriber status, classify accurately, and update it if your situation changes. Misclassification can mean owing back fees.