McDonald’s prevents fake survey submissions on the mcdvoicecom survey by implementing several security measures. Each receipt contains a unique survey code that can only be used once, ensuring that only genuine customers provide feedback. Additionally, surveys have participation limits per household within a specific timeframe to prevent excessive submissions. McDonald’s may also use IP tracking and data analysis to detect suspicious activity, such as repeated submissions from the same device. By requiring details from the receipt, like store number and visit date, McDonald’s ensures that survey responses come from real customers who have recently visited a restaurant.