# How to study citation overlap across ChatGPT, Gemini, Claude and Perplexity. - working worksheet

Reviewed alongside the Eli guide: https://hireeli.io/resources/research-ai-provider-citation-overlap

## Decision to make

Measure whether AI assistants rely on the same sources for commercial questions

Owner: ____________________
Review date: ____________________
Canonical page or destination: ____________________

## Buyer questions

- [ ] Do ChatGPT, Gemini, Claude and Perplexity cite the same sources?
- [ ] Should overlap be measured by domain or URL?
- [ ] What can citation overlap not prove?

## Evidence-led work plan

### 1. Use two overlap levels

Measure exact URL intersection and normalized domain intersection.

Evidence or artifact: ____________________
Status: [ ] not started  [ ] working  [ ] verified  [ ] blocked

### 2. Fix the question context

Use the same commercial question and market window.

Evidence or artifact: ____________________
Status: [ ] not started  [ ] working  [ ] verified  [ ] blocked

### 3. Classify the source ecosystem

Separate owned product pages, independent publications, reviews, directories, community threads, documentation and research.

Evidence or artifact: ____________________
Status: [ ] not started  [ ] working  [ ] verified  [ ] blocked

### 4. Publish limitations

Answers are stochastic and source interfaces differ.

Evidence or artifact: ____________________
Status: [ ] not started  [ ] working  [ ] verified  [ ] blocked

## Source ledger

- [ ] OpenAI: publishers and developers FAQ: https://help.openai.com/en/articles/12627856-publishers-and-developers-faq
- [ ] Perplexity: crawler documentation: https://docs.perplexity.ai/docs/resources/perplexity-crawlers
- [ ] Google Search Central: AI features and your website: https://developers.google.com/search/docs/appearance/ai-features

## Measurement boundary

Baseline date and exact context: ____________________
7-day observation: ____________________
14-day observation: ____________________
30-day observation: ____________________
Known limitations: ____________________

Keep technical eligibility, citations, recommendations, visits, leads and revenue as separate evidence. This worksheet does not guarantee an external ranking or commercial result.