Measuring whether users notice that a recommendation widget is actually advertising means paying attention to behavior, not just impressions. Looking at click patterns, scrolling habits, and time spent near the widget can reveal whether people treat it like a genuine recommendation or recognize it as a promotion. User feedback, surveys, and follow-up actions provide clues about trust and transparency. If users quickly ignore the widget, they may see it as an ad. If they engage with it similarly to organic recommendations, the advertising may blend into the experience. Comparing performance across different labels, placements, and designs helps identify what users perceive. Over time, these insights can improve disclosure practices while maintaining relevance.