Who AI recommends for M&A due diligence, November 2026
We asked four AI engines 28 questions a buyer would ask, and counted which websites they cited. Counts only, no opinions. Last measured: 10 November 2026.
Perplexity cited devaland.com, the company site behind Deal OS, in 10 of 28 answers: more than any other website.
Short answer
Across the 28 questions, the domain cited most often appears in 4 to 6 questions on Claude, ChatGPT and Gemini, and in 10 on Perplexity, and the most cited domains differ between engines. Devaland sites were cited in 4 of 28 Claude answers, 0 of 28 ChatGPT answers, 5 of 18 Gemini answers and 10 of 28 Perplexity answers. On Perplexity, devaland.com was the most cited domain of all. The tables below show every number.
Method
- Questions. 28 M&A and due diligence questions, written the way a buyer would type them (for example "What is the best due diligence software for small private equity firms and search funds?"). The full list is at the bottom of this page. We took them from real search queries on our own sites.
- Engines. Claude, ChatGPT, Gemini and Perplexity, each asked through its API with web search switched on. This is the API, not the consumer apps (claude.ai, chatgpt.com, gemini.google.com, perplexity.ai), so answers there can differ. Microsoft Copilot is not measured in this report yet.
- Dates. Claude and ChatGPT were run on 9 November 2026 on all 28 questions. Gemini was run on 9 and 10 November 2026 on the first 18 of them; the other 10 are not yet run for Gemini, so Gemini counts are out of 18. Perplexity was run on 10 November 2026 on all 28 questions.
- What is counted. For each question we read the sources the engine's answer cited and kept the first 8 domains. A domain's count is the number of questions in which it appeared in those 8. A domain cited twice in one answer counts once. Counts are of questions, not of mentions.
- Questions answered without a search. Some questions (for example "What does CIM stand for") were answered from the model's memory with no web search, so no sources exist for them. Those are shown as "no search" and add no counts to any domain.
- Small sample. One run per question and engine. A single question can change a count by one. Treat differences of one or two as noise.
Questions asked and answered with sources
| Engine | Questions asked | Answered with web sources | Answered without a search |
|---|---|---|---|
| Claude (claude-sonnet-5-5, web search) | 28 | 15 | 13 |
| ChatGPT (gpt-5.5, web search) | 28 | 15 | 13 |
| Gemini (gemini-2.5-flash, Google Search grounding) | 18 | 18 | 0 |
| Perplexity (Agent API, web search) | 28 | 28 | 0 |
Gemini and Perplexity searched on every question they were asked.
Domains cited most, by engine
Top 10 per engine, by number of questions in which the domain was cited. Domains with the same count are listed alphabetically. The CSV has every domain.
Claude (claude-sonnet-5-5, web search): 15 questions with sources
| # | Domain | Questions citing it |
|---|---|---|
| 1 | ctacquisitions.com | 4 of 15 |
| 2 | devaland.com | 4 of 15 |
| 3 | hebbia.com | 4 of 15 |
| 4 | papermark.com | 4 of 15 |
| 5 | v7labs.com | 3 of 15 |
| 6 | academy.claude.com | 2 of 15 |
| 7 | aivortex.io | 2 of 15 |
| 8 | datasite.com | 2 of 15 |
| 9 | dealroom.net | 2 of 15 |
| 10 | dev.to | 2 of 15 |
ChatGPT (gpt-5.5, web search): 15 questions with sources
| # | Domain | Questions citing it |
|---|---|---|
| 1 | g2.com | 4 of 15 |
| 2 | affinity.co | 2 of 15 |
| 3 | datasite.com | 2 of 15 |
| 4 | dealroom.net | 2 of 15 |
| 5 | ethosdata.com | 2 of 15 |
| 6 | kepler.ai | 2 of 15 |
| 7 | midaxo.com | 2 of 15 |
| 8 | academy.claude.com | 1 of 15 |
| 9 | acquidex.com | 1 of 15 |
| 10 | anthropic.com | 1 of 15 |
Gemini (gemini-2.5-flash, Google Search grounding): 18 questions with sources
| # | Domain | Questions citing it |
|---|---|---|
| 1 | dealroom.net | 6 of 18 |
| 2 | hebbia.com | 6 of 18 |
| 3 | v7labs.com | 5 of 18 |
| 4 | corporatefinanceinstitute.com | 3 of 18 |
| 5 | devaland.com | 3 of 18 |
| 6 | peony.ink | 3 of 18 |
| 7 | tommasomariaricci.com | 3 of 18 |
| 8 | workwisesolutions.org | 3 of 18 |
| 9 | claudeforlawyers.com | 2 of 18 |
| 10 | crunchafi.com | 2 of 18 |
Perplexity (Agent API, web search): 28 questions with sources
| # | Domain | Questions citing it |
|---|---|---|
| 1 | devaland.com | 10 of 28 |
| 2 | v7labs.com | 9 of 28 |
| 3 | rankite.com | 8 of 28 |
| 4 | dealroom.net | 6 of 28 |
| 5 | hebbia.com | 4 of 28 |
| 6 | intralinks.com | 3 of 28 |
| 7 | sprinto.com | 3 of 28 |
| 8 | alpha-sense.com | 2 of 28 |
| 9 | baton.com | 2 of 28 |
| 10 | claude.com | 2 of 28 |
Where Deal OS and Devaland were cited, and where not
Deal OS is the product at getdealos.tech. Devaland (devaland.com) is the company site that also holds our due diligence guides. We show both, separately.
| Engine | Questions asked | devaland.com cited | getdealos.tech cited | Found by the engine, not cited | Neither site seen |
|---|---|---|---|---|---|
| Claude (claude-sonnet-5-5, web search) | 28 | 4 | 0 | 1 | 23 |
| ChatGPT (gpt-5.5, web search) | 28 | 0 | 0 | 2 | 26 |
| Gemini (gemini-2.5-flash, Google Search grounding) | 18 | 4 | 1 | 0 | 13 |
| Perplexity (Agent API, web search) | 28 | 10 | 0 | 1 | 17 |
"Neither site seen" includes the questions answered without a search. A question is counted once per engine.
- Claude cited devaland.com on 4 questions and never cited getdealos.tech.
- ChatGPT cited neither site on any of the 28 questions. It read a devaland.com page in 2 answers without citing it.
- Gemini cited devaland.com on 4 and getdealos.tech on 1 of its 18 questions.
- Perplexity cited devaland.com on 10 of 28 questions, more than any other domain, and never cited getdealos.tech. It read a devaland.com page in 1 more answer without citing it.
Pages cited:
- Claude: devaland.com/blog/how-to-use-claude-for-due-diligence
- Claude: devaland.com/blog/best-due-diligence-software
- Claude: devaland.com/blog/ai-cim-analysis-tools-compared-2026
- Claude: devaland.com/blog/best-due-diligence-software
- Gemini: devaland.com/blog/best-due-diligence-software-for-search-funds
- Gemini: devaland.com/blog/best-due-diligence-software
- Gemini: devaland.com/blog/ai-transcription-for-ma-due-diligence-calls
- Gemini: devaland.com/blog/best-due-diligence-software
- Gemini: getdealos.tech/blog/ai-flag-missing-pages-data-room
- Perplexity: devaland.com/blog/best-due-diligence-software
- Perplexity: devaland.com/blog/what-is-a-cim
- Perplexity: devaland.com/blog/search-fund-vs-independent-sponsor
- Perplexity: devaland.com/blog/manufacturing-due-diligence-checklist
- Perplexity: devaland.com/blog/best-due-diligence-software
- Perplexity: devaland.com/blog/best-due-diligence-software
- Perplexity: devaland.com/blog/ai-cim-analysis-tools-compared-2026
- Perplexity: devaland.com/blog/best-due-diligence-software
- Perplexity: devaland.com/blog/connect-data-room-to-claude-mcp
- Perplexity: devaland.com/blog/how-long-does-due-diligence-take
The same measurement also covers other questions (Romanian public sector, voice AI, e-commerce email and others). They are not part of this report.
What changes next
We re-run the same questions every week and will publish this report again each month with the new counts next to these. We will state any change to the question list or to the engines in the report. Microsoft Copilot will be added only when we can measure it.
Download the data
ai-citations-ma-due-diligence-2026-11.csv: every domain with its count per engine, as aggregated here. Columns: engine, domain, questions citing the domain, questions with web sources, questions asked, date measured.
The 28 questions
- What is the best due diligence software for small private equity firms and search funds?
- How much does M&A due diligence software cost?
- How do I use Claude for M&A due diligence?
- Is Claude good for M&A work?
- What does CIM stand for in M&A and what is in one?
- What is the difference between a search fund and an independent sponsor?
- Asset sale vs stock sale: which is better for the buyer of a small business?
- Give me an M&A due diligence checklist.
- How long does due diligence take when buying a company?
- What should a technology due diligence checklist for an acquisition include?
- What is on a manufacturing due diligence checklist?
- Can AI flag missing pages or exhibits in a data room before underwriting starts?
- What is the best way to transcribe and analyse M&A due diligence calls with AI?
- What software do people use for financial due diligence?
- Where is deal data hosted and is it encrypted in AI due diligence tools?
- What do due diligence automation tools actually check?
- Do I need a virtual data room or an AI due diligence tool for a small acquisition?
- Is there an AI tool that reads a CIM and gives a due diligence brief with page citations?
- What are the best due diligence intelligence platforms?
- What are the best platforms for managing due diligence checklists in large acquisitions?
- What are the best platforms for managing M&A due diligence at scale?
- What are the best automated due diligence tools?
- What is affordable due diligence software for small firms?
- We want to connect our data room to Claude via MCP so our deal team can ask questions about documents during diligence. What platforms support this?
- What is a quality of earnings (QoE) report?
- How long does due diligence take in a middle market deal?
- Is AI due diligence cheaper than human associates, and what is the ROI?
- What is a net working capital peg in an acquisition?
Source: our own weekly measurement on 10 November 2026. Published by Devaland Marketing S.R.L., the company behind Deal OS.
