Business

Data Retention and Deletion for AI Tools: What to Ask a Vendor

Antonio Evans8 min read

A procurement analyst at a desk holds a printed list of eight questions next to a laptop showing a vendor's security page.
Key points

Key points

  1. 1Ask four groups of questions in writing: storage and subprocessors, retention by data type, who can access data, and how deletion propagates to backups.
  2. 2Treat "no training on your data" as an unverified sentence until the vendor names its subprocessors, quotes retention in days, and closes the anonymized-data carve-out.
  3. 3Retention is not one number: prompts, outputs, logs, embeddings, and backups each follow a different clock, and the longest clock governs your exposure.
  4. 4Written answers in the DPA, BAA, or contract are the only ones that survive a vendor acquisition, a model change, or an audit request.

Start by separating processing from training

Two things can happen to a document or prompt you send to an AI tool, and only one of them is reversible. Processing uses your data in real time to complete a task; when the task finishes, the data does not re-enter the system for future learning. Training feeds your content into a model so it becomes part of what the model knows, and there is no undo: getting your content back out means retraining, which nobody has budgeted for (Parseur).

That distinction drives everything else. Model inversion, the reconstruction of training data by querying a trained model, and cross-tenant contamination, where one customer's documents influence another customer's output, are the two failure modes that make training clauses worth negotiating (Parseur). Neither shows up in a vendor's security portal.

Insist on separate answers for each pillar. A comparison of typical vendor positions looks like this:

Data typeTypical default retentionWhat to ask for in writing
Prompts and inputs30 days for abuse monitoring on some platformsNamed retention window, and whether zero data retention is available
OutputsOften the same as promptsWhether outputs are stored separately from your conversation history
System and metadata logsLonger than content, often unstatedLog schema, fields captured, and retention period
Embeddings and vector indexesRarely disclosedWhether vectors are derived from your tenant only and how they are purged
BackupsUsually the longest clockRotation schedule and whether deletion reaches backups
Support tickets and attachmentsHandled outside the main productWhether support copies are scrubbed and after how long

The Future of Privacy Forum's internal policy checklist is a useful internal companion because it forces you to define, before you shop, which categories of company data may enter an AI tool at all (FPF).

The exact questions to send: storage and subprocessors

Storage questions fail when they are vague. "Where is data hosted?" invites "in the cloud." Ask instead:

  1. In which countries and regions is data at rest for each data type in the table above?
  2. Which cloud infrastructure providers host production, disaster recovery, and backup environments, and in which regions?
  3. Provide the current subprocessor list, including model providers, speech and OCR services, vector databases, and support tooling.
  4. For each subprocessor, state what data it receives and under which flow-down terms.
  5. Does any data leave the region of origin, and under which transfer mechanism?
  6. If the model is third-party, is your data sent to that provider's API, and under what retention terms?

The last question matters more than buyers expect. Many AI products are wrappers around someone else's foundation model, so your data may reach an organization you never negotiated with. DataGrail's analysis of 2,400 popular business software providers found that 63.6 percent of vendors advertising AI capabilities do not disclose a third-party AI subprocessor anywhere in their legal documentation (Parseur). From the outside you cannot tell the vendors with no subprocessor apart from the ones that simply did not name theirs.

Fourth-party risk is where healthcare reviews break down first, because an AI vendor may depend on a model provider, cloud platform, speech-to-text service, or vector database your team never picked (Censinet). HHS has stated that a cloud service provider can be a business associate even when it cannot view encrypted ePHI or does not hold the decryption key, which is why the subcontractor list belongs in the contract rather than the sales deck (Censinet).

Retention: ask per data type, in days

Retention answers are where a single word hides four clocks. Ask for a number, in days, for prompts, outputs, logs, embeddings, and backups, and ask what happens at the end of each period: deletion, anonymization, or indefinite retention in aggregate form.

Public vendor documentation shows how varied the defaults are. OpenAI states that business customers control how long their data is retained in ChatGPT Enterprise, ChatGPT for Healthcare, and ChatGPT Edu, and that business data is not used for training by default (OpenAI enterprise privacy). On another provider's account tiers, standard retention for abuse monitoring is documented as 30 days even when training is disabled, and temporary chat prevents history and training use but still retains content for 30 days for abuse detection (Secure Privacy). GitHub, for its part, told the community that individual Copilot users would receive 30 days of advance notice before interaction data could be used for model training, while agreements with Business and Enterprise customers prohibit that use (GitHub Community).

A worked example shows why the longest clock matters. Suppose your deletion obligation to a customer is 30 days. The prompt is deleted from the primary store on day 30, the log entry is deleted on day 90, and the backup containing both rotates on day 180. Your practical deletion date is day 180, not day 30. If your contract with your own customer promises 30 days, you have a gap you cannot close by asking the vendor to "delete promptly."

Boil every answer down to three fields you can compare across bidders: the longest retention period in days, the data types attached to it, and the mechanism that shortens it (an admin setting, a contractual term, or a support request). If the vendor cannot name the mechanism, assume the default applies to you.

Access: who can see it, and under what conditions

Access questions usually get answered with a list of security certifications, which says nothing about who opens your prompts. Ask:

  • Which roles inside the vendor can view customer content, and under what approval?
  • Are support engineers able to view content, and is that access gated, logged, and time-limited?
  • Do human reviewers read prompts for safety or quality, and can that be disabled?
  • Is content used for evaluation, benchmarking, or fine-tuning, including by affiliates?
  • Which third parties receive content, and is any of it sold?

Vendors differ on human review, and the differences are contractual. OpenAI documents that business data may pass through automated content classifiers and safety tools, and that human review applies on a service-by-service basis (OpenAI enterprise privacy). Other providers describe prompts as potentially reviewed by human reviewers for safety reasons, with no way to opt out when content triggers their safety systems (Tiamat on dev.to). GitHub says its own and Microsoft personnel working on model development may access interaction data collected for training, and that service providers may assist under contractual limits (GitHub Community).

The insight most reviews miss is that zero data retention does not mean zero data access. Every provider can see your prompt in transit, because it must filter it and respond to it (Tiamat on dev.to). Design your controls around that reality. If a workload cannot tolerate any human or automated inspection of content, scrub identifiers before the request leaves your network:

scrubbed, entity_map = pii_scrubber.scrub(user_input_with_pii)
response = client.chat.completions.create(
    messages=[{"role": "user", "content": scrubbed}]
)

The model sees a placeholder, not an account number, and the mapping stays in your environment (Tiamat on dev.to). Harvard's security guidance makes the same point from the policy side: understand what protections apply to the specific tool, model, workspace, and feature in use, and remove unnecessary personal or proprietary information before sharing content with an AI system (Harvard Information Security).

Deletion: self-serve or ticket, and does it reach backups?

Deletion questions have a short version and a useful version. The short version ("do you delete data on request?") gets a yes. The useful version asks how:

  1. Can we delete prompts, outputs, and files ourselves from an admin console, or does deletion require a support ticket?
  2. What is the stated completion time for a deletion request, and is it in the contract?
  3. Does deletion propagate to backups and disaster recovery copies, and on what schedule?
  4. Are derived artifacts (embeddings, indexes, cached responses, fine-tuned adapters) deleted or rebuilt from remaining data?
  5. What proof do we receive: a confirmation record, a certificate, or a log entry?
  6. How do legal holds interact with deletion, so the vendor does not keep extra data forever to satisfy them?
  7. What happens to our data if the contract ends, and how long does export access last?

Ask for default retention, backup retention, and deletion attestations as separate answers, because vendors often publish the first and skip the other two (CTO Input). The rule to repeat to your legal team is that if a commitment is not in the contract, it does not exist (CTO Input).

How to read the answers you get

Score answers against evidence, not adjectives. A vendor that says "we retain data only as long as necessary" has given you nothing you can put in a risk register; the sentence has no scope, names no subprocessors, quotes no retention number, and carries nobody's signature (Parseur).

Use four tests on every reply:

  • Specific or general. Days, regions, and named entities count. "Industry standard" and "as required" do not.
  • Document or assurance. A DPA clause, a subprocessor list with dates, or a SOC 2 report scope counts. A marketing page does not. Ask for the security report and the bridge letter, not a summary (CTO Input).
  • Default or negotiated. Ask what applies to your account under your contract, not what is available in some tier.
  • Silence or refusal. A vendor that will not answer in writing has answered. Hold the deal (Censinet).

Two documents do the heavy lifting. A data processing addendum carries the GDPR obligations, and vendors such as OpenAI will execute one for business and API use (OpenAI enterprise privacy). For health data, a business associate agreement plus a written no-training term is the floor, not the ceiling (Censinet). Fold the answers into one scoring sheet that covers data inputs and outputs, retention and training use, security posture, subprocessors, and exit, so procurement, security, and legal read the same artifact (Initialize AI).

Run a two-week proof before you scale: send one real workflow through the tool with scrubbed data, check the admin console for the retention settings you were promised, submit one deletion request and time it, and read the logs to confirm what was actually recorded. Evidence from your own tenant beats any questionnaire.

If you need a single endpoint to test several model types under one contract before committing your production data, Quanta Inference provides text, image, video, audio, and embedding models through one OpenAI-compatible API key, prepaid and priced in US dollars, which keeps the data-handling review to one vendor instead of five: https://quantaintelligence.ai/inference. For teams that want the retention questions answered alongside a working prototype, a free consulting call can map your obligations to a specific architecture: https://quantaintelligence.ai/calendar.

FAQ

FAQ

Is "we do not train on your data" enough to approve a vendor?

No. The sentence is free to write and usually names no subprocessors, quotes no retention number, and carries no signature, which is why security reviews have moved to checkable commitments: named subprocessors, retention stated in days, and a closed anonymized-data carve-out (Parseur). Pair it with a written no-training term in the contract and a retention schedule for prompts, logs, and backups.

Why does the backup period matter more than the deletion button?

Because backups usually carry the longest clock. If primary storage deletes on day 30 but a backup containing the same content rotates on day 180, your effective deletion date is day 180. Ask for the backup rotation schedule and whether deletion requests propagate to disaster recovery copies, and put the longer number in your own customer commitments.

What does zero data retention actually guarantee?

It means your data will not be used for training, and it typically does not mean nobody sees it. Providers still inspect prompts for abuse and safety, log metadata such as API key, timestamp, and token counts, and may route traffic through content moderation services (Tiamat on dev.to). Redact identifiers in your application if the content itself cannot be inspected.

Which roles should I ask about, beyond the vendor's own staff?

Ask about support engineers, safety and quality reviewers, affiliates, and every subprocessor that touches content, including model providers, speech services, and vector databases (GitHub Community). For health data, get a named subcontractor list and flow-down terms before any PHI moves downstream (Censinet).

How should I test the answers before rolling out widely?

Run a short pilot with real but scrubbed data in your own tenant. Verify the admin retention settings exist, submit a deletion request and time how long it takes, and read the audit logs to see which fields are captured. Require a signed DPA or BAA, a current security report, and a subprocessor list before you expand beyond the pilot, and record pass or fail criteria up front (CTO Input).

Sources

Sources

  1. No Training on Your Data Is Free to Say - 12 Questions That Test It
  2. FPF Releases Generative AI Internal Policy Checklist To Guide ...
  3. AI Vendors Want Your Data. Here Are the Six Questions to ...
  4. Enterprise privacy at OpenAI
  5. GPT-5 Training Data Opt-Out: How to Exclude Your Content from AI ...
  6. FAQ: Privacy Statement update on Copilot data use for model training ...
  7. The AI Training Data Opt-Out Lie: Why Your Prompts Are Being Used ...
  8. Best Practices: Using Generative AI - Harvard Information Security
  9. AI Vendor Due Diligence Checklist (Privacy, Bias, and ...
  10. AI Vendor Evaluation Checklist & Comparison Criteria
About the author

About the author

Antonio Evans
Antonio Evans

Antonio Evans is the founder of Quanta Intelligence and a fractional CTO who builds HIPAA-ready AI systems for health and life-science companies. Before that he was technical co-founder of FriendsEAT for twenty years, CEO of Socialdraft, and a data engineer at IBM. Antonio lives with his dog Santino in Lisbon, Portugal.

All articles