What is Content half-life?
Content half-life is the rate at which a page loses its AI citations as it ages without being updated, reflecting that recency is now a hard ranking signal in AI search rather than a minor freshness bonus.
How it works
Generative engines, especially real-time ones, treat freshness as a retrieval factor. Content that is not refreshed decays out of the citation set even if it was once authoritative, because the engine prefers current sources.
The decay is measurable. In rawmktg's analysis, pages not updated in 90 days were 3.2x more likely to lose their AI citations entirely, which reframes maintenance from optional polish to a core part of holding visibility.
Content half-life vs evergreen content
Evergreen content assumes a topic stays valid for years with little change. Content half-life recognises that in AI search even durable topics need a refresh cadence to keep their citations, because the engine rewards recency regardless of how timeless the subject is.
Why it matters for B2B
It turns maintenance into a ranking lever. A programmatic refresh cadence on your highest-value pages is often the cheapest way to defend AI visibility you have already earned.
Bumping the visible "updated" date without changing the content. Engines weigh actual substantive change, not the timestamp, so a cosmetic date edit does not reset the decay. Pages untouched for 90 days were 3.2x more likely to lose their citations entirely.