Context
Google Search Central documents Preferred Sources for publishers and states that content from a user-selected preferred source can be highlighted with a preferred badge in AI Mode and AI Overviews.
What changed
Google provides publisher-facing implementation methods for Preferred Sources and explicitly documents availability in AI Mode and AI Overviews.
Why it matters
This introduces a user-controlled source-preference layer into AI-mediated Google discovery, distinct from general ranking optimization.
Visibility OS interpretation
Treat Preferred Sources as a user-specific source preference signal, not as a universal ranking factor or guaranteed visibility boost.
What remains uncertain
Google does not disclose the magnitude of the exposure effect, query-class variation, or interaction with other source-selection signals.