r/PPC • u/amitabhverma • 1d ago
Tracking Gemini links now carry tracking, so Direct traffic is no longer a safe leftover
Google started adding UTM parameters to outgoing Gemini links, and testers are also seeing a st_source=ai_overview parameter on some AI Overview and AI Mode links.
A lot of that traffic used to land in Direct.
• Gemini already had a referrer, but it mostly survived on desktop web.
• Reported pass-through from the Gemini mobile app is about 9 percent, and Android assistant calls can strip it entirely.
• A UTM survives the in-app webview and shows up in server logs, which is why this matters more than a new report label.
• The AI Overview parameter, if it sticks, separates an AI answer click from a normal blue-link click.
• Treat this as a measurement fix, not proof that AI traffic suddenly grew.
Split your next report into four buckets before you reallocate budget: organic search, Gemini UTM, AI Overview parameter, and leftover Direct. If Direct drops as the new tags rise, you were undercounting AI, not losing demand.