The half-life of AI citations: What 3.5 million citation events taught us about AI’s memory

Nothing lasts forever—AI citations included.

Citations shape AI answers and provide a direct link from those answers to your brand and products. Naturally, teams want to be the source AI links out to—and to stay there.

In partnership with the team at Stacker, we analyzed 3.5 million citation events across AI platforms from September 2025 to March 2026. We tracked cohorts of sources that appeared in a given week, measured how many were still being cited in subsequent weeks, and calculated a half-life: the number of weeks it takes for 50% of a cohort’s citations to disappear.

The short version: for the average source, citation activity drops by half in about 4–5 weeks. But “average” hides meaningful variation by platform, industry, and source type. The takeaway for marketers and SEOs: durable AI visibility requires both offense (earning new citations) and defense (retaining the ones you have).

Platform plays a major role in citation durability

Across all sources, citation activity halves in roughly 4.5 weeks, but platforms behave differently:

Implication: the platform you’re optimizing for strongly influences how often you’ll need to “re‑earn” citations.

Industry differences exist but are narrower than platform effects:

A healthcare brand cited on Perplexity (~5.8 weeks) can still outperform an insurance brand cited on ChatGPT (~3.4 weeks)—platform selection carries more leverage than vertical alone.

Some sources have longer shelf lives

Citations from editorial domains in the Stacker Partner Network (4,000+ news publishers) last roughly twice as long as the average non‑Network domain. This advantage persists across every platform and industry we analyzed.

This creates a compounding structural edge: while typical sources re‑earn citations monthly, partner‑associated editorial domains tend to hold positions substantially longer.

What this means for content, SEO, and attribution

How Scrunch helps you measure, compare, and act

Scrunch’s Monitoring & Insights and AXP give teams a full loop: measure visibility, diagnose issues, prioritize opportunities, and deliver AI‑optimized content back to agents.

Practical workflows and how‑tos

Pros and cons of using Scrunch for AI search optimization

Pros - End‑to‑end visibility: brand presence, citations, sentiment, prompt placement, agent traffic, and competitive share in one place. - Cross‑model benchmarking: measure performance across platforms, then zoom into each to tailor strategy to its refresh cadence and citation patterns. - Prioritization built in: Influence Score, citation consistency, and Insights help focus limited time on the most impactful fixes and sources. - Action layer with AXP: deliver AI‑optimized content to agents, improving parse quality and citation likelihood without redesigning human pages. - SEO‑friendly workflows: topic cluster planning, prompt tracking, and page‑level audits map cleanly to content and technical SEO processes.

Considerations - Ongoing management required: faster‑refresh platforms (e.g., ChatGPT) benefit from more frequent monitoring and content updates. - Prompt coverage matters: you’ll want a representative set of prompts across the journey; under‑sampling can skew conclusions. - Ecosystem variability: platform behaviors evolve; Scrunch smooths noise with 2–3 week trend windows, but short‑term volatility can still occur. - Third‑party citations: winning durable editorial citations often requires coordinated content and outreach beyond your owned pages.

Is Scrunch user‑friendly for SEO and content consultants?

Yes. The workflows align with how consultants operate: define topic clusters, set representative prompts, benchmark visibility across platforms, then use page‑level audits and Insights to prioritize updates. Visual trend lines and side‑by‑side comparisons make it straightforward to show clients where visibility is rising or falling and why. If you’re comfortable with SEO tools and analytics, Scrunch’s learning curve is minimal, with new AI‑specific concepts like agent traffic and citation consistency clearly explained in‑product and in the help content.

How Scrunch measures brand impact vs. competitors

Scrunch provides analytics to quantify impact and compare against peers:

Further reading and recent resources

What to do next

If you’re ready to operationalize this, you can start a 7‑day free trial or book a demo to see how Monitoring & Insights and AXP work together to help you win—and keep—AI citations.

A note on methodology

We tracked cohorts of cited sources over time, measured weekly decay, smoothed short‑term volatility, and stabilized smaller groups via partial pooling. We used 200 bootstrap resamples to estimate confidence intervals and selected models based on holdout performance. Estimates reflect aggregate citation persistence across many prompts and weeks, not rerunning the exact same prompt repeatedly.